Here's the thread that started this project going. (http://www.diystompboxes.com/smfforum/index.php?topic=80407.0)
Here's the build document. (http://www.aronnelson.com/gallery/main.php/v/Taylor/)
PCBs are here. (http://www.diystompboxes.com/smfforum/index.php?topic=83423.0)
I have received some emails with questions about the project so I thought it would be a good idea to start this thread to have these questions and answers available to all who might be wondering.
QuoteI wasn't sure about the orientation of the NSL32 - can you help me understand how to orient that?
The optocoupler orientation goes like this: the LED side is the one with the short legs, the resistor side has the long legs. The resistor orientation doesn't matter, just like a regular resistor. The LED does matter. The negative side is the one indicated by a little white dot. The PCB has a + sign next to one of the pads, obviously put the positive (non-dotted) side here and the dotted side next to it. Then feed in the resistor-side legs.
QuoteI don't know about the dot you're talking about. Mine doesn't have one at least. One end, I think it was the short lead side, has writing on it. The other is glossy smooth. I have the writing side on the + side of the PCB. Is there a way to measure with my DMM?
I believe you have it in wrong. The end with writing on it is the resistor side. The glossy side is the LED, and the dot marks the negative LED lead.
Are you sure you've got an NSL-32? They should all have the white dot. As with all things, the datasheet reveals much:
http://www.alliedelec.com/Images/Products/Datasheets/BM/SILONEX_INC/Silonex-Inc_Actives-and-Passives_6995014.pdf
There is a way to check with a DMM, but it's convoluted. Connect 9v to a 10k pot's center lug, and connect one of the short NSL-32 leads to one of the outer lugs of the pot. Connect the other NSL-32 lead to ground. Put your DMM in resistance mode, in the 200k setting, and put a DMM lead on each of the long leads. You should have some resistance. If the resistance you measure varies by turning the pot, then the short lead connected to the pot is the positive one. If there's no resistance, or it doesn't change, then flip the short leads around and try again until you can make the resistance change by moving the pot.
Now, that's a pain, so I'd recommend first verifying that you have the right optocoupler, and trying to figure out why there's no polarity mark on it.
Is there a pot recommended for the wave distort that would make it easier for separating the wave types or is it fairly obvious....I haven't built it yet. Doing parts order now. I was thinking it might be hard to cram all those symbols around one pot. Or is there a way to instead wire up a selector switch with resistor values that would correlate with the wave...for example 1k=ramp up, 2k = ramp down...etc
Yup...already asked, found it. Sorry for the hassle.
Glad you found your answer, but note that wave distort and waveform select are different. The Wave Distort knob definitely should be a pot, not a switch, as it's a continuous control. The waveform select can, as you found, be made into a rotary switch, but I don't find that to be necessary, it's fairly obvious which one you have selected.
Here's a link to the post about making any knob a rotary switch instead of a pot, for anyone else who might wonder:
http://www.diystompboxes.com/smfforum/index.php?topic=80407.msg698237#msg698237
Ah, I see. The wave distort kinda acts like the symmetry knob on the lune. I will take your advice on the wave select and stick with the pot. I'm ordering parts tomorrow and hope to get a build report up soon. Also, got the board and parts and all looks well. Thanks! Can't wait to get this up and running!!
How would you compare this trem to something like the goatkeeper? Obviously smaller but seems like it can do a lot with the parts.
This circuit is without question the most full-featured and versatile DIY trem. But it doesn't do quite as much of the exotic stuff as the Goatkeeper.
So here's a question. In the other thread someone asked about using rotary switches instead of pots for the multiplier and waveform controls. I found the documentation on such but I was wondering how difficult it would be to attach 3mm LEDs to add some wow factor. Would be sweet if you could use the rotary switch to select between waveforms/multiplier and then also have an LED light up next to whichever position you choose.... thoughts?
Well, assuming you'd want to keep the available waveforms, you'd need a big switch, or go to electronic switching. You'd need a DP8T I guess, to switch both the voltage dividers and LEDs in 8 positions (6 for the multiplier). Such switches exists, but once you go above 3P4T rotary, it starts getting expensive/hard to find.
Here's one I found just now:
http://uk.digikey.com/1/1/290879-switch-rotary-dp-8pos-enclosed-c2p0208n-a.html
You could also do electronic switching. This would be very complicated. The common CMOS switching ICs I know of are mainly built around a bunch of double throw switches together, so you'd need a SP8T (which is somewhat common) and then maybe 4 4066's I think, and you would connect the enable pins of 2 of the CMOS switches together; one would be for an LED and one for the voltage divider. This conglomeration of one throw of the rotary switch, plus 2 CMOS switches in a 4066, would equal a double pole single throw. So you'd duplicate that 8 times. I guess at that point a $24 switch starts looking reasonable.
What about using an LM3914 (http://www.national.com/ds/LM/LM3914.pdf) in combination with an SP8T rotary?
It's usually used as an audio indicator, I think. I've never used one, but ten minutes of research indicates that it can be set to respond to a different range of voltages with just a couple of resistors.
Set it up so that the lowest waveform voltage triggers the first LED, and the highest waveform voltage triggers the eighth LED. Use the same CV coming off the SP8T to trigger the LM3914, which lights up the appropriate LED.
Just a thought. :)
Mike
Quote from: Taylor on May 01, 2010, 02:50:54 PM
Well, assuming you'd want to keep the available waveforms, you'd need a big switch, or go to electronic switching. You'd need a DP8T I guess, to switch both the voltage dividers and LEDs in 8 positions (6 for the multiplier). Such switches exists, but once you go above 3P4T rotary, it starts getting expensive/hard to find.
Here's one I found just now:
http://uk.digikey.com/1/1/290879-switch-rotary-dp-8pos-enclosed-c2p0208n-a.html
You could also do electronic switching. This would be very complicated. The common CMOS switching ICs I know of are mainly built around a bunch of double throw switches together, so you'd need a SP8T (which is somewhat common) and then maybe 4 4066's I think, and you would connect the enable pins of 2 of the CMOS switches together; one would be for an LED and one for the voltage divider. This conglomeration of one throw of the rotary switch, plus 2 CMOS switches in a 4066, would equal a double pole single throw. So you'd duplicate that 8 times. I guess at that point a $24 switch starts looking reasonable.
You could also use two 4051s to give 2P8T, instead of four 4066s, to save some space and complexity.
However, I also like the idea of using an LM3914 with indicator LEDs. I wonder if one could use the pot method with this instead of a rotary switch. The LM3914 seems to have "dot mode" which I think means the LEDs turn on one-at-a-time, rather than as a group with the brightest in the centre. I need to do more reading on this.
Christopher
I partially completed my TTT last night (no switches) and am pretty pleased with it. I tuned out the ticking as best I could, but I then had trouble getting to unity gain. Would it be possible to bring the gain trimpot outside and replace it with a 50k audio pot for more volume?
Yep, that's certainly possible.
Somebody posted this over at Electro-Music.com, thought it was really cool so I'm posting it here:
Quote from: synthmongerFinally got around to building this. Fun to play around with but most of the wave forms don't affect the amplitude as much as I hope. I've modularized mine so I can get more use out of it.
My feet are kinda big so I had to stick the stomp switch up top so I could avoid hitting the tempo and multi switch.
(http://hphotos-snc3.fbcdn.net/hs297.snc3/28496_1499637330229_1213023959_31439902_7894303_n.jpg)
(http://hphotos-snc3.fbcdn.net/hs297.snc3/28496_1499637970245_1213023959_31439903_4129939_n.jpg)
So, like an idiot I did something wrong when I went to solder everything up.. I put the 22k trimpot in the gain location when I was actually wanting to put the gain knob external, so I desoldered the trimpot and pulled it out and it took off the pads on the top of the board.. Looks like two of the pins for the pot have traces on the bottom, but then one of them has a trace on the top, going to the tl072.. Looks like pin 7.. Just want to confirm that I should just run the wire from my pot directly to that pin.
Hmm, that's a tough one. Perhaps I need to do a tutorial on desoldering from double-sided boards?
The issue here is that that pin of the trimpot connects to pin 7 of the TL072, and also to the 330p cap and 1uf cap. The pad lies between the connection of the opamp and the caps, so you've severed not just the connection to the trimmer, but the connection of the opamp to the caps. You'll need to run 2 wires from that pin of the trim: one to pin 7 of the opamp and one to the caps. Look to the schematic to be sure you're correcting these properly.
I'm having a bit of a hard time using the schematic to verify this..
What I have done so far is on the new pot I'm using, I've wired (looking at the back of the pot) the lug on the left and the wiper directly to one of the pins on the nsl-32 (where I could see the trace running on the back for those two connections of the trimpot), and then I have the right lug wired directly to pin 7 on the tl072. You're saying I should jumper from that right lug on the gain pot to the 330p and 1uf cap also? Which pins on those two caps?
Also, what is the correct orientation for the rest of the pots if I'm looking from the perspective of the back of the pot.
Really appreciate it.
vvvvvvvvvvvvvvvvvvv
Tomorrow I'll post some images here to help answer both questions.
(http://img64.imageshack.us/img64/1419/taptremliftedtrace.th.jpg) (http://img64.imageshack.us/i/taptremliftedtrace.jpg/)
This shows better than words how that pot is connected, so it should show you how to wire everything. The bottom layer is blue, the top is red.
I didn't have time to take a picture of the pots, but looking at the board so you can read the silk screen, the clockwise lugs go to the left, and ccw to the right.
Cool.
Just to be 100% clear on pot orientation, are you saying clockwise and counterclockwise looking at the back of the pot with the lugs facing up?
I've got it built, but I've got ticking. It's not too bad but I can't completely get rid of it. The biggest issue I have right now I guess is that I get the ticking noise even when it's bypassed..
How could that be happening?
So it would seem that the LED being connected through the 3pdt switch even when disengaged causes ticking in the bypassed signal.
I think What I'm going to do is add a second LED which is only there to be on/off if the pedal is engaged/bypassed, the other LED connected to the PCB will be directly connected.. That might be a bit weird since it will always be on when there is power, but I think it will be handy for setting my tempo and seeing that tempo in the pcb led even when the pedal is disengaged.
As for the ticking when engaged.. I guess I'll have to start checking components. Would it be worth upping the values of the trimpots I'm using so that I've got more play there? I suppose I could wire a resistor in series with the pots somehow to bring their values up a bit..
Or is it more likely that my optocoupler is noisy. I did buy a second one of those as well.
I only really hear the ticking when I've got the waveform set to the hard on/off settings.. When it's set to the sinewave setting I don't hear the ticking.
I find replacing the opto i the easiest way to fix ticking. But the audio section of this is identical to the tremulus lune, so searching for ticking fixes with that circuit will turn up lots of things you can try if the new opto doesn't fix it.
Well, this is frustrating. I've tried my new opto and the ticking didn't change as far as I can tell. It is pretty mild and happens when it's doing the square wave, but it's still there.
I've looked thru some of the tremulus lune forums. A couple things I tried are putting a .001uf cap over the gain pot, and a 100uf cap from v+ to ground. Those things didn't seem to make any difference. Am I just being too sensitive, should there be absolutely no ticking at all regardless of waveform and volume?
Anyone else run across this?
I do have some ticking with some optos. Others seem to have no ticking in square mode. It is a pain to have to sort them, so I've talked to Tom about doing a version of the code where the square and ramp waves are just barely angled. This is something we may have together at some point in the future.
I think I've got it pretty good now. The volume at which I need to have the amp when on the square wave and still hear ticking is so loud that you would never notice the ticking anyways. That and I'll be primarily using the sinewave anyways, which I have no ticking with.
One thing that I noticed is that (in my case anyways) to reduce any extra noise when the pedal is engaged, having that .001uf cap over the gain pot helps.
That's actually what the 330p cap is already doing, so what you've done by adding that cap is to up the capacitance there to 1.33n. I may make a suggestion in the PDF to use a bigger than 330p cap there.
I believe the 330pF cap is what was originally in the schematic for the Tremulus Lune.
When I built my (non tap) version of this, after I figured out that too much current to the LED was causing a lot of ticking, I ended up using a 1nF cap in that position to get rid of the ticking once and for all.
Mike
First off, thank you Taylor and .Mike for all of your hard work (and to the others that contributed).
I have a question about the pdf under Modifications. It says, "Any pot can be modded for CV input easily." Is that referring to adding an expression pedal? I think that makes sense but would like to verify.
Thanks!
Sort of. What I'm referring to there is that, for guys with modular synth systems, or more experimental folks, you can send a control voltage (CV) to the pot inputs directly. So synth guys could use this with their modular systems which send all control signals as CV (and since 0v-5v is, I believe, a common CV format, it works perfectly with the TAPLFO chip). This way you could have a sequencer change the waveform on every beat, or an LFO scrolling through multiplier settings for extreme animated weirdness.
If you just want to add an expression control, you don't need to think about voltages or anything. Simply wire a jack to the 3 pads of the pot you want to replace, making sure that you wire it to be in compliance with the expression pedal you're using (they're all wired differently). Use a switching stereo jack so that when you unplug the expression pedal, the pot becomes active.
Taylor:
I am finally getting around to building the tap tempo tremolo using the board and chip I got from you.
I have a question about the multiplier that I can't seem to find an answer for in the forum thread or your build pdf.
If I install the SPST momentary contact switch at the EXP pads on the board to use this to step through the multiplier stages what do I do with the multiplier pot? Do I leave it in or replace it with resistors?
You can have both a switch and the pot if you want. If you use the switch, it steps to the next multiplier, then if you move the pot, it overrides the switch setting. If you don't want a multiplier pot at all, I guess you'd want to stick 5k resistors from the 5v and gnd pads and have them both meet in the center pad.
Thanks, That's interesting. I understood how using the rotary switches in place of the pots would work, but I wasn't certain about the multiplier. I'm don't know how they manage to do it, but from your explanation the SPST switch takes precedence and then if you adjust the pot the chip goes back to using that as the control. I'll build it with the SPST and the pot and see how that works. It's sort of like wearing a belt and suspenders at the same time.
Taylor,
Thanks for your reply; that makes sense. I don't do any of that, so I guess I'm fine without it.
I am proud to report that I finished the build, and it works perfectly. I was easily able to tune the circuit, using the trim pots, to get the hum out of the circuit. I will get a full report with pics and comments up soon.
One thing to note (and I think you said this earlier, Taylor), I would keep it simple and not add the rotary switch. It is very easy to figure out which waveform you have selected. Also, the multiplier with both pot and switch function just as said, each takes precedence over the other when changed. I am going to play with it more, but I am leaning towards just going with the pot. The switch doesn't let you switch back and forth between settings; it just lets you move through the series. I don't think that it would help me "on the fly" (but I guess it would save me from having to bend over and change settings), and I think I would rather have more foot room, especially if I'm tapping.
It would be pretty easy to rig up a stomp switch to swap between 2 multiplier pots if that's what you wanted. You only need to swap the center pin so you could use a DPDT stomp (or SPDT even). Then you could preset them as you please and switch back and forth mid-song.
Hi all,
I have my tap tempo completed, but I am running into a snag that can't be lived with. When I send a signal generator it works fine, but when I send a passive signal(guitar) all I get is a really weak signal and massive ticking... I have put a second optocoupler in and it still is not mitigating the ticking. I have also adjusted the two trimpots all to no avail. Any ideas? And thank you Taylor for all your help thus far.
Cheers,
Eli
I'd start by swapping the 330p next to the opamp for something above 1n, as noted a few posts up.
If a stronger signal seems to work but a weak signal doesn't, maybe the input signal is being reduced. Maybe the signal generator can overcome the loss, but the guitar can't.
Check the values of R11 and R12 and make sure they are correct (220K). If R11 is larger (I think) than R12, it would attenuate any incoming signal.
Mike
Quote from: Taylor on June 03, 2010, 10:05:33 PM
I'd start by swapping the 330p next to the opamp for something above 1n, as noted a few posts up.
Of course if I would have read first I would have seen that huh? :) I can be impatient at times, I am sure it is what lead to the problem I am struggling to fix now. I will try the cap change, also I will check those resistors. Thanks guys.
-Eli
Since I'm putting an order in at Smallbear for a few things, I figured I'd try a different optocoupler, just to see if I can completely get rid of the ticking I have.
I sent a few PM's to taylor regarding it, so I've posted them below my further questions regarding optocouplers, in case anyone else was thinking of doing something similar.
The datasheet for the NSL-32 shows 500ohm on @ 20ma and 500K off resistances, and 3.5msec rise / 500msec fall times.
In looking at those Vactec datasheets,
I see from the graph that the VTL5C10 shows about 50ohm on @ 20ma and 400K off resistances, but a shorter rise time and longer fall time.. 1msec rise and 1.5sec fall.
The VTL5C7 also looks interesting, in that it's 6msec rise and 1sec fall (maybe this is more what I'd be after, but again the on/off resistances are different.. what bearing does that have on things?) It looks to be about 50ohms on @ 20ma also, and 1Mohm off.
I'm leaning towards trying the VTL5C7, but I am hoping to get some suggestions on what to try. Basically I'd like to try something that will soften any ticking that might occur.
Quote from: PMs to Taylor
Quote from: thehoj
I'm needing to order a few things from smallbear for something else in the next few days, and so I was thinking (even though the ticking I was seeing on the trem is so minimal and only on square wave) maybe I would try another optocoupler.. Is there a different one all together that might be worth trying, that smallbear would stock?
Quote from: Taylor
Hey, I haven't tried any others yet, but the best thing to do would be to check my PDF to see what resistances I recommend (I forget at the moment) and compare the NSL-32's rise and fall times to those of some of the vactecs. If you find a vactec with longer time, it should tick less.
datasheets:
http://www.alliedelec.com/Images/Products/Datasheets/BM/SILONEX_INC/Silonex-Inc_Actives-and-Passives_6995014.pdf
http://www.elenota.pl/upload/VTL5C2.pdf
Quote from: thehoj
You mention 500ohm on and 500Kohm off.
The rise and fall times of the NSL-32 are 3.5 and 500msec respectively.
What do the rise and fall times translate to in this circuit? Will having a longer rise or fall time affect the speed of the tremolo?
Quote from: Taylor
Each cycle of the LFO, the opto rises (goes from zero volume to max volume) and then falls (goes from max to zero volume). This creates the tremolo effect. If you find an opto with slower times, it will round off the hard edge of the square wave slightly, which will alleviate ticking. It doesn't change the speed of the trem, only the time it takes to go from silence to full volume, and at the times we're talking about, thousandths of a second, you don't hear the difference really. It just makes the transition a little softer so the momentary current pull is spread out a little bit which should fix the ticking.
So I got around to diming my amp and playing with the gain pot to adjust for bypass / on volume levels. The best combination I found (0-10 scale) was gain at 10, trim in front of TL072 at 10, and trim behind TAPFLO at ~6. With anything less than 10 on the trim in front of the TL072, my led went really dim and the ticking got very loud. Is that typical? I am using a bright blue LED, VAOL-5LSBY2.
Regardless, at those settings I was able to remove almost all of the ticking. With the depth set at full, it wasn't ticking, but could hear is bottom out (if that makes any sense). But it was fine. BUT when I bypass the pedal, I get a loud ticking. This seems very odd to me. I wouldn't think any ticking would get passed on the bypassed path. With the depth down, it wouldn't tick, but with full depth it was very loud. I guess that is bleeding through on the ground path? But I don't understand why it isn't there when the pedal is engaged.
I am going to try the 1n cap that keeps being discussed. But the ticking in bypass perplexes me.
On a similar but different note, I am modding my silverface twin reverb. In doing so I found some interesting info. Of such, I found some info on taming the ticking in the trem circuit. Paul Marossy said, "I had a ticking coming through the speakers from the vibrato. So I installed a .022uF capacitor in parallel with 10M resistor at the optoisolator." http://www.diyguitarist.com/GuitarAmps/TwinReverb.htm
The loop he is referring to has a 1M, to the first lead of the Opto side of the optoisolator, to the second side of the opto, to a 100k, to the other side of the 1M. The Schematic is here: http://www.ampwares.com/schematics/100W_Mast_Vol_SF_Twin_Rev.pdf
I don't know if something like this would help, but I figured that I would throw it out there.
On a couple of them that I've built, I can hear ticking in bypass at high volume. Pretty faint, but annoying enough, so I came up with an alternate LED bypass scheme. I'll draw up a diagram tomorrow, but basically I ground the PWM signal after the 10k coming from [pin 5 I think] of the taplfo. It will be clearer when I can post the diagram, but this totally does the job.
Quote from: joinpobob on June 05, 2010, 01:41:09 AM
This seems very odd to me. I wouldn't think any ticking would get passed on the bypassed path. With the depth down, it wouldn't tick, but with full depth it was very loud. I guess that is bleeding through on the ground path? But I don't understand why it isn't there when the pedal is engaged.
I had the exact same thing. It seemed to be because I had the LED wired through the 3pdt switch.
I got around it with a bit of a different approach. I used 2 LEDs.
Firstly I wired the LED that connects to the PCB, directly, so it's always on if there's power connected to the pedal. Then I wired a second LED to the 3pdt switch which comes on to indicate that the pedal is engaged.
What this means is that I can see the tempo of the pedal even when it's not engaged.
So with the 1st LED being wired directly to the PCB, I have my 3pdt switch wired up as follows (sorry for the crappy pic):
(http://vwtweaked.ca/images/trem3pdt.jpg)
Thank you both for your replies. I already had the box drilled for one pedal so I went with Taylors suggestion. Now it works perfectly. Something to take home to mama.
So now my build has all stock, except for an added 1nF in the feedback loop of the TL072 (so a total of 1n33F). Then the LED is soldered straight to the "pos" and "neg" pads. Finally, the 10k resistor coming off of pin 5 on the TAPFLO has one leg lifted (the one towards the "top" of the board) with the to-be-grounded wire coming off of the lifted leg and the the positive side connected to the open pad. Then those wires are soldered to the switch as you would a "regular" 3PDT (so the LED column is positive>>to-be-grounded>>Ground). Hope that makes sense.
Thanks so much for your help, Taylor and thehoj.
Quote from: thehoj on June 04, 2010, 02:46:49 PM
I'm leaning towards trying the VTL5C7, but I am hoping to get some suggestions on what to try. Basically I'd like to try something that will soften any ticking that might occur.
Yes, that looks like a good one to try.
I finally found time to finish putting the TTT together. After resolving an issue with a 9V jack that I had never used before the pedal came to life. Works great...... with a few caveats (and hence questions).
I mounted the three pots that go on the board on the same face as the rest of the components with the body of the pots away from the board.. This seems to make them work backwards from my expectations. Should they be on the other face? No problem to change them.
I have NO ticking but, then again, I have no LED. I do have voltage at the LED pads (bouncing all over the place around 3V) and it does respond to the trimpot on the right. However, I have yet to see even a glimmer of light from my LED. I have explored several LEDS, and checked (even reversed) the polarity without success. I have attached the LED directly to the board to avoid issues with the stomp switch and still no luck. I can live without the LED, but I would like to resolve the issue if possible. Any suggestions?
PS: I have to make a confession. While trying to figure out the different 9V jack I was getting voltage readings well below what I should have seen. I did note that the schematic calls for a 9 - 12V supply, so I unplugged my regulated 9V supply (Small Bear) and hooked up my regulated 12V supply (same design as SB, different transformer and resistors to control the output - it works just fine to run my Vibratone Amp based on Rick Holt's design). Well.... I let the smoke out of the 10 ohm resistor just on-board from the PS. Replaced the resistor and neighboring dioide just in case, pulled out the 9V jack and put in one I have used before and the tremolo worked fine. No harm, no foul.
Your LED situation is pretty weird. If the trem is working, then the transistor that grounds the LED is working. If you have voltage at the POS pad, that means that what's on the other side of the LED is working. So assuming you're using a regular LED that works and you have it in right and your soldering on those pads is good, I can't think of any other reason that it wouldn't work. I guess all I can say is: double check that you have 9v going into the board, and reflow your solder connecting the LED to the board. And try a new LED.
The pots should be the other way, yes. I need to add a photo to the PDF to show this, just haven't gotten around to it yet.
Thanks for the reply. I pondered the pots before installing them. I had already populated the rest of the components and it was difficult to follow traces to determine the correct orientation. I chose wrong. Easy to fix.
I'll work on the LED some more. The pedal does work exactly as it should, and as I mentioned, I do have voltage at the pads. I tried three different LEDS without success. The ones I had in the bin were unlabelled, so I do not know their exact voltage requirements. I'll get some new LEDs and see if that fixes things.
I pulled the pots and put them on the proper side of the board, rewired the power input since the leads were now too short when the board was flipped, and installed a new LED (a nice 8mm high-brightness blue LED from Smallbear).
Everything works just fine :icon_smile:
I may have to tweak the trimmer for the LED brightness a bit. There is little adjustment and then at the end of the travel the LED is full on. An appropriate resistor in parallel should do the trick. I am still dumbfounded as to why it was not working yesterday. Perhaps it has to do with the small amount of adjustment I am getting for this particular LED and maybe the one I had installed was just over the limit.
The tremolo sound is very nice. I haven't played much with the different waveforms, but it is easy to tell when the chip switches modes as you rotate the pot. I may still decide to go for a rotary switch although I am concerned that this may introduce a pop when changing modes. The pot is silent.
I still have not heard any ticking, but I have only tried this at low volume levels. Perhaps I got a good optocoupler (thanks Smallbear :icon_mrgreen: ).
I put this is a pretty big box (Hammond DD) since I wanted to include both the tap tempo and multiplier switches without creating problems for clumsy feet. Not the most aesthetically pleasing when you see how much room there is left in the box, but it will do the job nicely.
Thanks again to Taylor and all of the others who contributed to the design of this pedal and for providing a source for the boards and chips.
Glad you got it sorted. :)
An update:
I tried to tweak the LED brightness, but never had much success getting a better range from the trimmer. What I did find is that my "no ticks here" observation had some limitations along with it. Very strange! My trimmer was varying the LED brightness below a good level and then came full on. At the full on setting I had very little (or no) ticking as I reported. As I tried to tame the LED I realized that at lowere brightness levels there was ticking, especially in bypass.
I had read the other comments about modifying the cap and I did that. I did notice that the lead dress had a lot to do with the LED ticking. I had unfortunately mounted my LED close to the input jack and the lines were talking to each other.
I decided to go with the two LED solution and added an "on/off" LED that is controlled by the stomp switch, moving the tempo LED to the other end of the box. The tempo LED stays on (I am not certain that I needed to do this with the other mods I did - I may play around with the pedal to see if I can get away with the close proximity of the LED signal near the in/out signals at the switch).
I replaced the wiring for the input and output signals as well as the tempo LED (and the short bridge on the switch) with shielded cable and made a star ground around the switch. There is NO ticking with this setup. Probably overkill, but it is one quiet pedal!
I got the wrong sized 330nf cap from mouser. Its the big block 334J100. Atleast I think thats the code for 330nf. Anyway, the pdf says cap values are just suggestions and I'm trying to get this working for this weekend. Any recommendations on a substitute? I have a lot of ceramics that would fit in there but not 330nf.
Edit: Also, I was reading the post above and saw the problem about the ticking. is 1n going to be the new 330pf or should I use something else?
The PDF says "cap types are just suggestions". This is because, I wanted to note the standard cap type to use in that position for beginners who don't know anything about different cap types and are overwhelmed trying to buy parts for projects. I thought it would make it easier if they could type in "ceramic 10pf capacitor" or whatever to Mouser so they didn't have to be baffled my the endless different cap types. But then I got a bunch of emails asking "can I use film caps instead of ceramic?", "I heard film caps sound better than ceramic, why did you spec crappy parts in this project???" So I added that little disclaimer, hoping people would get the idea that, you can use these cap types, but if you think you know something that will work better, use whatever makes you happy. Maybe I should have just written that. :icon_smile: But cap values are not merely suggestions: you should stick to them unless told otherwise or if you know better than I do.
For the record, the 22p caps that I recommended ceramic for are part of the digital LFO, so no matter what you might think about film caps sounding better than ceramic, I can say unequivocally that in this spot, it will make absolutely no difference. Crystal oscillators will not sound any more like Hendrix with a film cap to ground. :icon_wink:
Ok, that rant out of the way:
Yes, I'd use 1N instead of 330p.
The 330n is power bypass on the input of the voltage regulator. I think you'd be fine with something a little bigger.
Haha ok thanks for the clarification.. and the rant. If someone can tell the difference between a ceramic and a film, they should stop what they're doing and go on a gameshow or something cause thats pretty ridiculous. Anyway, 1n it is. If 330n is supposed to be there, I can bend the big one I have so it lays sideways off the end of the board and everything will be exactly like the list.
Just have those 2 caps then the led and wiring left to do. Am I doing the led like in the pdf or should I wire it to the board and lift that 10k above the chip and grounding it thing? (Still gotta read that dudes explanation a couple more times to get it). Just trying to get it done and introduce it to the rest of the board without any debugging.
Just to clarify, there could be some truth to different cap types sounding different when they are in the signal path. I still don't think it matters enough to care about, but there is at least a reasonable explanation for why it could matter. But the 22p ceramics are part of the digital section of this circuit, and not at all a part of the signal path, so they can have no influence over the sound.
Also for clarity, I'm wondering if you're getting confused about 330n and 330p. The 330N is on the far left of the board and is part of the digital LFO. You can use something a little bigger than 330N here.
The 330P is on the right of the board and is part of the audio section. Here you can use anything around 1N.
Regarding the LED, I have to draw a diagram to better explain that. I'll try to do it tonight.
Quote from: good air on June 23, 2010, 12:12:22 AMIf 330n is supposed to be there, I can bend the big one I have so it lays sideways off the end of the board and everything will be exactly like the list.
330n is not an absolutely essential value for C14. It's taken right from the datasheet for the regulator-- 330n on the input, 100n on the output. I've seen values all the way up to 100u on the input on some schematics. In fact, the 330n cap might not even be necessary. The datasheet says it is "required if the regulator is located more than 3" from the power supply filter." :)
Mike
I can't remember now what it was, but I have seen a lack of bypass cap on a regulator input cause a problem before. I was going to say he could leave it off too, but to be safe you may as well put something there, and you may as well make it bigger as Mike says.
Yeah, I can't figure out any rhyme or reason as to how people pick the value for the capacitor on the input. I'd love to know, though... heh.
I put the 1n in there in place of the 330p (next to the trimmer), I'll leave the 330n off for now to see how it works without it. I have a 1uf that will fit in there too.
Thanks in advance for the led diagram, I'll save that and the 3pdt for last. Almost done, glass is getting empty.
Here you go. I'll also add this to the PDF. Note that my way is a little different from joinpobob's suggestion. His leaves the PWM output of the TAPLFO floating when the circuit is bypassed, and while this seems to work for him, it's suppose to be bad practice to do this. In my diagram, I ground the PWM output in bypass through a 10k resistor instead of just disconnecting it.
(http://img820.imageshack.us/img820/6872/taptempotremalternateby.th.jpg) (http://img820.imageshack.us/i/taptempotremalternateby.jpg/)
Thanks man, just got home so I'll get started and let you know how it turns out.
Maybe a dumb question but whats are those pads that are in the traces on the board with no parts assigned to them? There's one next to the diode and one next to the cap on the left of the taplfo. Are they supposed to be filled with solder?
They make connections from the top side of the board to the bottom. You don't have to do anything to them. :)
Mike
gracias friend
Well ran into some problems with this last night, hoped to get it situated this afternoon but no luck. Got bypass, got led, reflowed joints, did some probing and getting tones up to the photocoupler but i'm not sure exactly where the tones stop (not too good at following schematics). No trem though and the show is in a few hours. Any ideas?
Is your LED flashing?
Do you have the opto in right? The long leads are the resistor side, the short leads are the LED side. The white dot on the opto is the negative LED lead, put the other side (the one without the dot) where the + sign is on the board.
Thanks for the fast reply. No led flashing. The white dot is opposite the + sign on the same side, the long leads are in the pads next to the trim pot. I'm uploading some pics now.
(http://img194.imageshack.us/img194/3431/boardfrontj.jpg) (http://img194.imageshack.us/i/boardfrontj.jpg/)
Uploaded with ImageShack.us (http://imageshack.us)(http://img714.imageshack.us/i/boardbackb.jpg/)
http://img194.imageshack.us/img194/3431/boardfrontj.jpg (http://img194.imageshack.us/img194/3431/boardfrontj.jpg)
(http://img714.imageshack.us/img714/9544/boardbackb.th.jpg) (http://img714.imageshack.us/i/boardbackb.jpg/)
Uploaded with ImageShack.us (http://imageshack.us)
What gauge wire are you using?
22
Check that you have 5v at pin 1 of the taplfo. See if you have any voltage on the pos leads of the LEDs, and what that voltage is if so. Check if the rightmost pin of the 3904 is connected to ground (probe the lead itself, not the pad).
It's tough to see whether you have solder bridges or just glare on the flux on your board, but it does appear that you have some long unclipped wires sticking out of the solder joints. It may not be the problem here, but it's good practice and will save yo headaches to clip everything right up to the joint.
Thanks for the tip on the long leads. Once its done, I'm going to clip everything and clean it up and put some cardboard on the bottom. I have a blue led to put in there too and the box isnt painted yet, just trying to use it tonight. Hopefully!
Anyway..
Got exactly 5 volts on pin 5 of taplfo and the led, opto has 4.9 on the postive.
Right most pin on the 3904 gave me the beep on the lead and the pad.
What is the purple lead that snakes around the LED pins and appears to terminate near the opto?
Thats goes from the middle pin of the 3pdt to the 10k resistor to wire the led. Taylor posted the diagram a few posts up.
Got it, I missed Tyler's post. It does look like you tried to tie into the thin trace to the 10K resistor rather than hitting the same hole in the pcb or tying into the leg of the resistor. Are you certain you haven't shorted out any connections here?
I also had some major league ticking problems and found that they were very dependant on the lead dress of the LED. I finally went for the nuclear option and installed a separate "effect on" LED and moved the tempo LED wiring away from the stomp switch. I also rewired the input and output lines and LED with shielded cable. I cannot tell you which of these changes worked the magic, but the pedal is dead silent in operation and in bypass.
Yeah i soldered it to the leg of the resistor. It lights up so thats good, no blinking though. I don't know anything about this particular wiring and shorts but first thing I did to debug was check for bridges/shorts and cold joints. Unfortunately it doesn't look like this is getting fixed tonight cause I gotta get everything together. Next month's show = massive trem. I'll be back tomorrow afternoon and hopefully you guys can help me get this going. Thanks!
I don't know how much you fiddled with the pots, but if you have it set on square wave with the wave distort all the way to left I think, it will be always on. Also, if you have the depth all the way down the LED will stay lit all the time. Do you have sound coming though when the effect is on and the LED is lit up but not flashing?
Alright I'm back. Hungover but back. I was messing with the pots a little and it didnt change the led, still doesnt blink, the trimpot adjusts the brightness but its just on. I have no sound coming out when the effect is on, I made an audio probe and poked around and get sound up until the opto but its not a tremolo sound anywhere. Any ideas on what parts to check out?
Hmm, it's weird, because if the TAPLFO was not functioning it would not put out a signal, so the LED shouldn't light. So the chip must be functioning but maybe you have a short in the wiring of the depth knob that causes it to be minimum depth.
Did you try tweaking the trim right next to the TAPLFO while probing the resistor side of the opto coupler? If the visible LED is lit, then the opto should light as well, which would give you audio unless the trim is too far in one direction.
Alright its getting there. Adjusted the trimpots and depth like you said and it blinks now. I also moved that purple wire away from the led. The Depth knob was the culprit because it had to be maxed out for blinking. Tap and multiplier switches work but its not really tremolo-ing. If I put the Depth all the way up and Wave Distort all the way down, I get trem but its more of a clean signal, not very deep. some settings on the Wave shaping knob are better at tremolo than the others. Going to mess around with the settings a little more.
Some of the waveforms are definitely on the subtle side, especially the "lumps" aka inverted hypertriangle. Set the wave distort in the center for all testing, then try to locate the square wave. It should be at about 11 oclock or 1 oclock on the waveform knob depending on how you have the pot wired. With that on, you'll need to adjust the trimpot next to the TAPlfo and the one above the opamp as discussed in the instruction PDF.
It sounds to me like it's working, so now you just need to tweak it into proper functioning.
Success.
:) :icon_exclaim:
Hey Taylor--
Which NSL-32 are you providing with this?
I'm working on putting together a parts order, and I'd like to order the parts for the tap tempo tremolo.
It looks like Silonex has 14 varieties (http://www.silonex.com/audiohm/index.html) of the NSL-32. ???
Both Smallbear and Newark have 3 different choices.
Thanks,
Mike
I've only used the plain old NSL-32 with no suffixes. The other ones that Small Bear has require more current to turn on, which could potentially mean more ticking. The 32B and 32H XXX might be something to try since they use less current but I don't know where you can get them. I could also be misunderstanding the current thing since I'm still no guru.
Thanks Taylor.
In looking at the datasheets, it seems like the SR3 is the fastest of the group with the widest resistance range, but it might be too fast. It also has a lower On resistance at 5mA than the regular NSL-32 does at 20mA. The SR2 apparently has a lower On resistance at 1mA than the regular NSL-32 has at 20mA. That might be a good choice to keep the current as low as possible.
I think I'll order one of each, socket, and compare.
Thanks!
Mike
Definitely forgot to take a picture so here it is.
(http://img441.imageshack.us/img441/9030/tremulusaires.jpg) (http://img441.imageshack.us/i/tremulusaires.jpg/)
Uploaded with ImageShack.us (http://imageshack.us)
Cool. :)
Thanks. 2 questions for adjustments.
I need more volume when the trem is engaged, getting a drop when I turn it on, gain pot is already maxed - is it possible?
and what are the chances of putting a sequencer in there in the future? :icon_biggrin:
Quote from: good air on July 15, 2010, 08:10:33 PMI need more volume when the trem is engaged, getting a drop when I turn it on, gain pot is already maxed - is it possible?
Yes. R15 and the LDR portion of the optocoupler work with the opamp as an inverting amplifier. Increasing the value of R15 will increase the gain.
Quoteand what are the chances of putting a sequencer in there in the future? :icon_biggrin:
I'm sure it can be done with a PIC, but it probably wouldn't be a drop-in replacement.
:)
Mike
By "gain pot is already maxed" it sounds like he already has increase R15 (in my PCB it's a trim) as far as it can go. You could add a series resistance, but in my experience there should be tons of gain on tap with that knob. What you need to do is change the setting of the trim right next to the TAPLFO - this sets the current limiting resistance of the optocoupler, and you must have it trimmed way down so the opto is just barely turning on.
By sequencer do you mean something like a ZVex Seek Trem? We could ask Tom but I don't think the PIC 16f684 used in this project can be configured with enough pot inputs for that. So you'd need to go up to a bigger microcontroller I think.
If you just want a tap tempo Seek Trem kind of thing, I think it would be possible to do that by combining the tap trem with a Vanishing Point (see tech.thetonegod.com), and using the clock output of the TAPLFO to clock the decade counter.
Quote from: Taylor on July 15, 2010, 09:20:11 PM
By "gain pot is already maxed" it sounds like he already has increase R15 (in my PCB it's a trim) as far as it can go. You could add a series resistance, but in my experience there should be tons of gain on tap with that knob. What you need to do is change the setting of the trim right next to the TAPLFO - this sets the current limiting resistance of the optocoupler, and you must have it trimmed way down so the opto is just barely turning on.
By sequencer do you mean something like a ZVex Seek Trem? We could ask Tom but I don't think the PIC 16f684 used in this project can be configured with enough pot inputs for that. So you'd need to go up to a bigger microcontroller I think.
If you just want a tap tempo Seek Trem kind of thing, I think it would be possible to do that by combining the tap trem with a Vanishing Point (see tech.thetonegod.com), and using the clock output of the TAPLFO to clock the decade counter.
You could actually do a drop in replacement chip for a seqencer on your board. You could use a momentary switch on that "extra" pin to toggle between the pots for the setup (I.E. set a pot value, then hit the switch to go to the next one). Maybe use one of the LED's already set up (the tap LED or the clock) to indicate when you are back at the beginning of the "pot row". Hell, you could make it into as many "pots" as you want... Want a 50 potentiometer sequencer? :icon_lol:
All the control pots/switches/leds on that chip are basically "blank slate" inputs. You can rewrite the code to do whatever you want with them.
Lesse, the tap chip has these controls/ports
Tap switch input
Extra function switch input
Depth
Multiplier
Speed
Waveform
Wave distort
Clock LED
Tap LED
So maybe change them to:
Tap switch input -> Same
Extra function switch input -> Next sequencer potentiometer
Depth -> Same
Multiplier -> Same
Speed -> Same, or maybe instead (since with the tap tempo you can replicate it) something like "order of sequencer" (forward, backwards, forwards+backwards, random)
Waveform -> Sequencer Potentiometer
Wave distort -> Smoothing? That'd be complicated in code, though. # of sequencer pots?
Clock LED -> Same
Tap LED -> same, but also flashes twice or something when you end up back at the start of the sequencer pots
All it would take is changing the chip out on the board and you can flip between wave trem or sequencer trem.
That sounds pretty cool. I just meant that it wouldn't have the 8 pots minimum simultaneously to emulate something like the Seek Trem. It would be a little less immediate just stepping through pots, and also difficult to remember how you had set all the pots with no visual feedback, but that's ok with me.
Would it be possible to piggyback the chips and enable one or the other via toggling the power pins?
And when will your code be ready? :icon_wink:
Quote from: Taylor on July 15, 2010, 09:20:11 PM
By "gain pot is already maxed" it sounds like he already has increase R15 (in my PCB it's a trim) as far as it can go. You could add a series resistance, but in my experience there should be tons of gain on tap with that knob. What you need to do is change the setting of the trim right next to the TAPLFO - this sets the current limiting resistance of the optocoupler, and you must have it trimmed way down so the opto is just barely turning on.
By sequencer do you mean something like a ZVex Seek Trem? We could ask Tom but I don't think the PIC 16f684 used in this project can be configured with enough pot inputs for that. So you'd need to go up to a bigger microcontroller I think.
If you just want a tap tempo Seek Trem kind of thing, I think it would be possible to do that by combining the tap trem with a Vanishing Point (see tech.thetonegod.com), and using the clock output of the TAPLFO to clock the decade counter.
I meant he could use a larger value resistor/trim/pot. :)
I think we're both kind of right. The maximum gain of the second opamp stage is directly related to the minimum resistance of the LDR. So, if you want to increase the gain of that stage, you can
either lower the minimum resistance of the LDR, or increase the resistance of the feedback resistor. If lowering the resistance of the LDR by increasing the current to the LED side of the photocell induces ticking, it may end up being an equally acceptable option to increase the size/add series resistance the value of the resistor/trim/pot. I think. :icon_neutral:
Couldn't you also increase the value of R12 to give some gain to the first inverting stage, instead of it just functioning as a buffer?
Quote from: JKowalski on July 15, 2010, 10:08:56 PMYou could actually do a drop in replacement chip for a seqencer on your board.
Cool! I'm surprised that that base chip hasn't been implemented into more designs yet. I think it's only a matter of time. :)
Mike
Quote from: .Mike on July 15, 2010, 10:28:56 PM
I meant he could use a larger value resistor/trim/pot. :)
I think we're both kind of right. The maximum gain of the second opamp stage is directly related to the minimum resistance of the LDR. So, if you want to increase the gain of that stage, you can either lower the minimum resistance of the LDR, or increase the resistance of the feedback resistor. If lowering the resistance of the LDR by increasing the current to the LED side of the photocell induces ticking, it may end up being an equally acceptable option to increase the size/add series resistance the value of the resistor/trim/pot. I think. :icon_neutral:
Couldn't you also increase the value of R12 to give some gain to the first inverting stage, instead of it just functioning as a buffer?
Yep, you're right. Maybe I'll play around with that some. The only thing is that you lose max depth when you trim the opto way down like that. If the opto isn't completely muting the signal when the LED turns off (which it probably isn't) and then you cut down the max level (bright LED) and amplify both the max and min levels, you end up with less contrast between loud and quiet. But it could still work and may help if you have ticking issues.
QuoteCool! I'm surprised that that base chip hasn't been implemented into more designs yet. I think it's only a matter of time. :)
Mike
Just imagine if somebody was putting together a DIY project for a 12-stage tap tempo phaser, using cheap, easily available parts that don't require matching? :icon_wink:
Yeah the trim pot is maxed. I adjusted the led and opto trimpots for maximum depth. There was absolutely no ticking at all when I was adjusting the trims, so that led to resistor diagram worked like a charm.
@.Mike - I was thinking the same thing with the gain trim, maybe raising it to 50k. I didn't do the external gain knob so I wanted to triple check before I desoldered the trim. Seems simple and effective but bringing this trem to a show this weekend and don't wanna mess it up. :D
QuoteIf you just want a tap tempo Seek Trem kind of thing, I think it would be possible to do that by combining the tap trem with a Vanishing Point (see tech.thetonegod.com), and using the clock output of the TAPLFO to clock the decade counter.
Thats EXACTLY what I was thinking about the sequencer. I was aiming for more of a goatkeeper sequencer, could be 4 steps, could be 8, just think your trem has a lot of potential for rhythmic beats combined with the waveshaping and tap tempo. I downloaded both Vanishing Point pdf's and thought it seemed very do-able. Then I went to the Electric Druid site and noticed the clock output and the empty pin.. So makes me think its possible if you just send the signal out of the chip ---> sequencer (vanishing point) ---)> back into the chip.. but its way out of my league to figure it out right now. Jkowalski's idea about the code has me very intrigued now. Hopefully you guys can make this happen cause as you see in the pic I used a pretty big enclosure and theres def some room for more fun in there. :icon_biggrin:
Quote from: Taylor on July 15, 2010, 10:43:08 PM
Just imagine if somebody was putting together a DIY project for a 12-stage tap tempo phaser, using cheap, easily available parts that don't require matching? :icon_wink:
If it makes any difference, my next build was going to be the Phaseur Fleur.. food for thought. ;)
Quote from: Taylor on July 15, 2010, 10:19:14 PM
That sounds pretty cool. I just meant that it wouldn't have the 8 pots minimum simultaneously to emulate something like the Seek Trem. It would be a little less immediate just stepping through pots, and also difficult to remember how you had set all the pots with no visual feedback, but that's ok with me.
Would it be possible to piggyback the chips and enable one or the other via toggling the power pins?
And when will your code be ready? :icon_wink:
Yeah, well that's what happens when you design around things :icon_biggrin:
Piggyback the chips? Hmm... I don't really know how the chip settles when it's unpowered, so I can't give you an answer on that. It might work fine.
Haha, hmm. I suppose I could try something... I'll let you know if I decide to work something out for it.
Quote from: good air on July 15, 2010, 11:36:55 PM
Quote from: Taylor on July 15, 2010, 10:43:08 PM
Just imagine if somebody was putting together a DIY project for a 12-stage tap tempo phaser, using cheap, easily available parts that don't require matching? :icon_wink:
If it makes any difference, my next build was going to be the Phaseur Fleur.. food for thought. ;)
I have an 10 stage version on a breadboard right now that I am finishing up. It uses FETs. I was considering OTA's and did try them but I couldn't do more then 4-6 stages since the 14-pin chips seriously start to fill up the board. I still am trying to figure out how to perfect the phaser controls and where to place the filter peaks. It is a phaser/vibrato combo.
The chip can basically be integrated into any design very easily. It just replaces the LFO, and then you got to work out the biasing. Filtering is easily done with three lo-pass filters in series - the PWM frequency can be massively attenuated without harming the sharp angles in the waveforms... but I have found it is best to push the filter a little lower to eliminate any thumping in the LFO's sawtooth, square, and random waves.
What I mean is that you don't really need to draw up new projects for the chip, just integrate into already made projects. I guess someone could flip through the most popular projects and draw up schematics with the chip integrated already... Hrmm. I'm hesistant to take on too many projects though, since I am finishing up a bunch I have had lying around forever right now and it's a real pain. Life is much simpler when you don't multi-task in your hobby. :icon_lol:
I'll have to post a sound clip of the
random waveform at high speed with deep phasing tomorrow. I think I have a vid of my brother fooling around with it I can pull it from.
It is so funny. It makes it sound like you are playing your guitar underwater.
My phaser plan was to use the PWM to switch 4066 switches with resistors both in series and parallel. These resistors would replace the FETs in a Phase 90-type phaser. This is cheap, uses available parts, and doesn't require any matching. I may need to clock the TAPLFO faster, need to check if that's possible.
Quote from: Taylor on July 16, 2010, 04:31:19 AM
My phaser plan was to use the PWM to switch 4066 switches with resistors both in series and parallel. These resistors would replace the FETs in a Phase 90-type phaser. This is cheap, uses available parts, and doesn't require any matching. I may need to clock the TAPLFO faster, need to check if that's possible.
You can't clock the PWM any faster without losing resolution in the waveform. It's a trade off between PWM speed and bit depth. You can't clock the whole chip any faster to enable both higher PWM frequency and good bit depth because 20Mhz is the maximum speed.
It's an interesting plan. You'd have to stick a pretty steep filter stage at the end, though, to remove the hash generated without edging into the audio band at all. I might take a look into PWM'd resistors sometime, I've never actually tried them out.
I think an 8-stage is the best choice for this, since it only takes two quad op amps and two 4066... Though you could use a univibe style transistor follower+phase splitter layout.
By the way, here's that funny phaser sound (http://mp3upload.ca/music/play/26945.mp3&type=sound). Don't mind the aimless noodling, I don't think my brother expected to be recorded :icon_rolleyes:
The Joe Walsh was inspired by
(http://images.amazon.com/images/P/B0017CW5E4.jpg)
Can anyone recommend some enclosure sizes for this project? I generally like to keep things pretty squished so it's as small as possible and can fit more on my pedalboard. :)
Also, the best place to get quality SPST momentary switches? I can't seem to find them on mouser, the all metal ones that look like regular stomp switches.
I believe I mocked it up in a 125b and it fit, if you really want it as small as physically possible. I built mine in a 1590bb and I like that size, any smaller I find is tough to switch.
I get my momentary stomps from ebay.
I put mine in a 1790NS. It could easily fit in a 125B, but I wanted two stomps and the 1790NS isn't that much bigger than a 1590BB turned sideways. It fits in nicely with 125B's also because of the height, and I use 125B's for smaller pedals mostly.
Jacob
Thanks. If I wanted to add the ability for an external tap tempo switch (in addition to the internal one), would it be as simple as installing another 1/4" jack wired to the same point on the PCB as the momentary switch?
Yep.
I'm planning on doing that with my second Trem... but first I have to get the first one working...
Jacob
Is it at all possible to control the speed with an expression pedal? I was listening to something earlier today where the guitarist played a chord with a tremolo and the tremolo speed slowed from fast to slow, I believe through an expression pedal.
Yes, as with any pot on anything, you can wire an expression jack to the speed pot pads. Make sure you wire it in accordance with the way your exp. pedal is wired; they're all different. Use a switching jack to connect the regular pot when your expression pedal is disconnected.
Just got back from holiday and literally threw this together last night. It fired up first try with very minimal ticking (on extreme settings), I didn't bother with any of the ticking fixes so I was pleasantly surprised.
Great work Taylor, very useful effect.
One question, I stuffed the board just using the silkscreen, when I checked the bom later for pot values the trims seem to be 22K whereas the board shows 10K. Which value should it be? I seem to be OK with 10K.
Thanks
- Aston
Quote from: Skruffyhound on August 10, 2010, 07:49:36 AMOne question, I stuffed the board just using the silkscreen, when I checked the bom later for pot values the trims seem to be 22K whereas the board shows 10K. Which value should it be? I seem to be OK with 10K.
The two 10K trimpots that are side-by-side (and marked as 22K on the schematic) are used as current-limiting resistors for the optocoupler LED and indicator LED. Either value should be fine there.
Mike
Cool, glad you had a nice build and are enjoying it. I appreciate the kind words, and want to pass them on to the other guys who made this project possible: .Mike, Tom Wiltshire, Jkowalski, and Dann Green.
Thanks Mike.
Quite right. Thanks to all the guys involved. I've actually followed this from the start and read all the associated threads so I know how much work you all did.
Now I'm going to build the next one, I want to hear what they sound like in tandem :D
Got my board and chip today, thanks! Will likely order another soon.
One question: the spot for an LED on the bottom of the board with the spots labeled NEG/POS. The PDF shows this wired to the bypass switch. Is this just for the bypass? Is it then optional to connect it to the board here? I usually don't have my LEDs on my boards.
Also, is there a way to connect a second LED to flash in tempo with the currently tapped tempo?
The LED does flash with the tempo already.
The bypass wiring in the PDF has kind of been replaced by the diagram in this thread:
http://www.diystompboxes.com/smfforum/index.php?topic=84020.msg713301#msg713301
Thanks. So if I am correct: the LED is completely off when the circuit is bypassed, and when the circuit is active it flashes with the tempo? So there is no separate basic on/off LED? How is its brightness determined compared to a "normal" LED where you would connect it straight to +9V with a resistor?
Yes, it's off when bypassed, on and flashing to the tempo when the effect is on. There is a trimpot to control the brightness on the board. You can make it as bright as you want, just as bright as an LED wired the usual way.
Cool, thanks. And what's the tiny hole UNDER the TL072 chip (not part of its 8 pins)? Does that connect to anything?
It's called a via (http://en.wikipedia.org/wiki/Via_(electronics)). You don't need to do anything with it; it allows a trace to move from one copper layer to another.
Got it, thanks! Also, I'm assuming crystals are non-polar?
Yes, that's right.
More questions...about the expression pedal jack. I assume I use a stereo jack? How exactly do I wire it to the pot? You mentioned every expression pedal is different...I have a Boss FV-500L, but am making this for a friend and I'm not sure what he may end up using. Is there one way that is most common? How does the Boss one get wired?
Also, the direction of the pot wiring? The board is not labeled, so I'm a bit mixed up.
I don't know how the Boss is wired, but what makes being a DIYer great is that you can easily pop it open and see for yourself since you have one. I use Moog EP-2s and wire my expression pedals for that.
Here's a diagram I drew a while ago to show how to do it. Use a stereo switched jack (one that has 6 contacts).
http://img689.imageshack.us/img689/8049/gizerspeedexp.png
This is done in accordance with the Moog exp. jack, which connects the tip to the wiper. Other expression pedals are different, so figure out how yours is set up before copying this diagram.
So, just got it all wired up...bypass works. When I engage the pedal the LED stays steady on and I get no sound. Any trouble shooting tips? Tried tweaking all the trimpots.
Both the IC and TAPFLO chip appear to be getting power just fine. I could post voltages if necessary.
Did you wire the wave distort as a pot or fixed resistors? If you used a pot, make sure you have it set to the center while testing.
The audio path is really simple, so it will be easy to probe through the circuit with an audio probe and see where your audio dies. Set the trimpots all to the center while testing.
Sweet, adjusted the pots and set the wave distort knob to middle and it works great now! Except the tap switch seems to be pretty spasmatic? Like I'll tap it to a tempo and it just kind of randomly seems to pick a tempo...
What kind of switch did you use?
This one: http://www.smallbearelec.com/Detail.bok?no=672
Hmm, that's what I'm using too. It may just be that you need to get the hang of how to tap with this particular circuit/PIC program. I had some problems too at first. I think the debounce part of the program could stand to be beefed up, but for the most part you'll figure out how to tap to get it to work. You need to hold the switch for just a bit longer than you think for each tap.
Got one more question...after I built this pedal I gave it to a friend and he said: "I tried messing around with the internal pots but I wasnt able to get the volume up enough to compensate for the drop."
Any ideas?
Did you experience the volume drop when you were testing it?
There are three trimpots. The two that are side-by-side control the current going to the LED and the photocoupler LED. Once set for minimum clicking or popping, they should be pretty much left alone. The other trimpot is for adjusting the gain, and if your friend doesn't quite know what he's doing, it is probably the only one they should mess with.
Also, make sure you have explained that the wave distort feature should be set in the middle. It alters the on time verses the off time. If it's up too high (or is it too low-- I haven't built mine off this board yet) so that there is a longer quiet period compared to the audible period, then the perception is that the overall volume has decreased.
Maybe Taylor has some other ideas. :)
Mike
Ya, I had the volume drop when I was testing it but I didn't try to adjust it so much because I thought that it would be different on every pedal board, depending on how your pedals are all set. I figured he'd have to adjust it anyway.
And the other trimpots shouldn't affect volume at all should they? Only the ticking? I don't think I set those well enough either.
The trimpot right next to the PIC controls the optocoupler, as Mike said. It definitely does affect the volume. More resistance means that the optocoupler doesn't light up as bright when on, which equals a lower max volume. If the gain pot doesn't allow unity gain even at max, it means that you don't have the optocoupler trim set right. It should be possible to adjust the gain trim to the point of getting huge distortion.
So you'll need to readjust the optocoupler trim, and possibly up the cap marked 330p if you need to have the trim dialed so far down to get rid of ticking.
Thanks! So the optocoupler trimpot that may affect the volume is the one directly next to the TAPFLO chip, correct?
Just ordered parts from Taylor. Excited!
Anyone have any finished pics for layout ideas?
Hello,
Sounds like a great build!
I can't see the PDF build instructions when I go into the galley; am I doing something wrong?
TT
Click on "no thumbnail", then on the next page, click on "download document".
Hi all,
I have a tremolo that needs a debug, and I'm afraid it's beyond my abilities! The issue is that it doesn't pass sound, only ticks. It appears the LFO is working properly, as the LED works, and changes when the pots are moved. I've poked around with an audio probe, but nothing really stands out. I'm getting clean signal at pin 1 of the TL072, but quiet ticking everywhere else. I'm getting loud ticking at the photocoupler.
Kinda frustrating as the audio part of the circuit isn't that complicated!
Just an update.
Been messing with it this morning. After it dawned on my that I should have signal at pin 2 of the TL072 (which I didn't), I resoldering the two 220ks and the TL072. The good new is I'm now getting signal through with tremolo. However, it's very weak and I got the gain trim maxed. I'm also getting ticking, but I also have the optocoupler trimmer quite high as that's the only way I get a strong signal. Not sure if the ticking is 100% related to that, or I have another problem.
Quick question about pot orientation - I typed out a long confusing thing, but pictures are much easier. 1, 2, 3 or 4 :icon_lol:
(http://i246.photobucket.com/albums/gg114/mth5044/potorientation.png)
Now that I think about it, 1 and 4 are the same, as are 2 and 3. Oh well. Also, will 16mm pots fit next to each other? I don't have the board with me now, so I thought I'd ask. Thanks!
I also want to say, great board Taylor. I really like the size of the pads and the layout!
You can use either 1 or 4 - I use 4. This allows to trim the trims once the pedal is all built. 16mm pots do fit all next to each other - I use the angled PC mount ones.
Thanks for the comments!
I have a question about using rotary switches for the waveform and multiplier controls. I have followed the instructions on the Tap Tempo LFO datasheet to wire the rotary switch for the waveform control but I'm not sure how I should do the one for the multiplier.
On the datasheet (p. 8 ) it is said that: "The top two options are not used for the Multiplier" Does that mean that two of the 10k resistors must be removed from the resistor string? Or do I have to keep all the resistors from the string and only remove the first two connections that go from the rotary switch to the resistor string?
Looking at the datasheet, it is the second one.
The datasheet also says: Note that values 6 & 7 are not used (set to x1) so the maximum useful CV is 3.75V
I did a quick sim of the string of resistors, and recorded the voltages. Check it out:
(http://img411.imageshack.us/img411/5316/tttrotaryswitchvoltages.th.jpg) (http://img411.imageshack.us/i/tttrotaryswitchvoltages.jpg/)
As you can see, the junction of R1 and R2, and the junction of R2 and R3, are both above the maximum useful CV of 3.75V, so you don't want to use them (they'll set the multiplier to 1, which is already covered by one of the throws of your SP6T rotary swtich). The other six resistor junctions are the usable voltages.
You can sub R1, R2, and R3 for a single 25K resistor (or probably a common value close to that, like 24K).
Mike
Thank you for your quick reply Mike
Keep in mind that that 3k6 resistor that feeds the clockwise lug of the multiplier pot limits the max voltage to 3.75v already. So if you're tapping from some other 5v point, Mike's diagram has you covered, but if you were going to take the positive voltage from the multiplier pot's clockwise pad, you'll need to adjust for that.
Mine is mounted and working fine.
(Thanks Taylor for your excellent PCB)
Maybe, as someone of you said, using a pot to select the waveform is not the best way. I'd like a 3 pos. switch to select SINUS, PULSE or RANDOM. Easy mod.
btw, I recommend the multiplier switch. It is very useful.
I'll try to upload some picture.
Taylor, I understand what you just said but I'm not really sure how I should adjust for that if I want to use the positive voltage from the multiplier pot's clockwise pad.
If I want to be able to use Mike's diagram, is it as simple as replacing R8 (3k6) by a jumper?
Another way to do it will be to keep R8 like it is and change the values of the resistors in the resistor string. But I don't know what those values should be nor how I could calculate them.
And just to be be sure, as there is no resistor that limits the max voltage to the waveform pot, if I want to use a rotary switch for that I don't have to make any adjustment like the one that is required in the multiplier case, right?
Quote from: Vince_b on September 29, 2010, 11:02:45 AM
Taylor, I understand what you just said but I'm not really sure how I should adjust for that if I want to use the positive voltage from the multiplier pot's clockwise pad.
If I want to be able to use Mike's diagram, is it as simple as replacing R8 (3k6) by a jumper?
Yes, that's one way and it will work fine.
Quote
And just to be be sure, as there is no resistor that limits the max voltage to the waveform pot, if I want to use a rotary switch for that I don't have to make any adjustment like the one that is required in the multiplier case, right?
Right, no adjustment necessary there.
I have just finished building my tap tempo tremolo. It worked fine on the first try, no debbuging to do! Thanks to everyone who have contribute to this fantastic project and a special thank to Taylor and Mike who helped me with the wiring of rotary switches.
Here is a picture:
(http://img832.imageshack.us/img832/3614/tremolo.jpg) (http://img832.imageshack.us/i/tremolo.jpg/)
When I will have time to finish the enclosure I will also post a picture in the picture thread.
But the only thing that bothers me with this tremolo is the brightness of the led. To remove the ticking I had to set the trimpot for the led to almost full intensity and it's so bright that I can't even looks at it when it's engaged. I have sanded the top of the led but it is still too bright. Does anyone have a solution for that?
I would swap out the 330p for something like 1n or 2n2. That should sort the ticking and you can adjust the trimmers to a more reasonable area.
Hey Vince, looks great. Any chance you have a picture of the top? I know you said it isn't done, but I'm still deciding on a layout :icon_confused:
Has anyone made clips of their Tap Tempo Tremolo? I'm waiting ona few more parts and mine is done.
I put up some crappy clips in this topic (http://www.diystompboxes.com/smfforum/index.php?topic=77471). The clips are in the first post, and there is a longer demo further down the page.
It's not a tap-tempo tremolo, but it uses the earlier non-tap VCLFO and a nearly identical supporting circuit. As far as I am aware, the waveforms are the same between the TAPLFO and VCLFO, so it should give you a very good idea of the flexibility and sound of the effect. :)
Mike
Got mine working great....only issue is that the Waveform Step Switch I wired onto the expansion pads doesn't seem to work? I used the same kind of switch that I used on the tap switch.
Any ideas why?
That switch doesn't step through the waveforms, it steps through multipliers. Do you have the 10k resistor on the edge of the baord next to the exp pads soldered in?
Oh, read the info wrong! Doh.
Yes, I have the left most soldered in, but I also have the wave distort soldered in.
Well, the wave distort won't have anything to do with the multiplier switch. So does it work to switch through multipliers?
Hm, I don't think so. Should the leftmost resistor be in there or not?
Yes, that leftmost 10k should be there no matter how you have the pedal configured. Is your switch normally open or normally closed (should be normally open)?
I finally built this but have some pretty bad ticking, only on the square wave though. I can't get rid of it at all, I've upped the 330p to 1.3n and it's still there. I'm using an NSL-32 that I got from taylor, and the only thing different I did was instead of using a 2n3904, I used a BC550 - which shouldn't matter? No wave distort knob. Any ideas? (almost everything else seems fine, perhaps a little ticking on a few of the other settings but not so bad)
also, I have ticking in bypassed mode. Setting the trims the ticking disappears in places but then you use a lot of volume, as I guess it turns off the nsl.
Normally open, I believe. It's the same kind of switch I used for the tap switch.
Oh, and I used the NSL-32 from smallbear, no problems with ticking whatsoever. I thought that might be useful to know. :D
update, I've fixed bypassed ticking(with taylors alternate bypass switching) but the ticking is still there when turned on, I've upped the cap to about 2.5n but no help. (I also put a 470n over there too which removed most of the ticking but ruined the tone)
Optocouplers vary from one to the next. Some of them have too fast a turn-on time, so you get ticking. That's why I recommend getting a couple in the PDF. So one solution would just be to get another NSL-32.
Also, there's a huge gap between 2.5n and 470n. :icon_wink: You could up that cap to 15n and probably fix it, without losing remotely the amount of high end you lose with a 470n.
Even with 470n there was still quite a bit of ticking, but yeah I think I'll try a few more photocouplers, would the VTL5C3 be any better? I'll also try another NSL-32...
Just wanted to say thanks for the fun project and hard work in putting something together for everyone to have fun with. I am still struggling with click, even after using a .0022, but only in the extreme settings at high volume. May try a VTL5C3 or order another NSL32 and see what happens. regardless, very versatile and good great sounding trem. Here are a couple pics of my build.
(http://img441.imageshack.us/img441/221/nov005.th.jpg) (http://img441.imageshack.us/i/nov005.jpg/)
(http://img690.imageshack.us/img690/1693/nov003k.th.jpg) (http://img690.imageshack.us/i/nov003k.jpg/)
If you're not using the visible LED (it's on the inside), I'd take it out of the board. That might make your tick disappear. Right now you just have it pulling current (which is the source of the tick) but not doing anything useful, unless you have a glowing floor setup happening. :)
Quote from: jonny on November 10, 2010, 08:50:19 AM
Even with 470n there was still quite a bit of ticking, but yeah I think I'll try a few more photocouplers, would the VTL5C3 be any better? I'll also try another NSL-32...
You should try another NSL-32, but have you properly set the trimpots up? If you have ticking with a 470n cap I'm guessing it's the trims that need adjusting.
I've mucked around with the trim pots for an hour or so, basically there are places where the ticking stops but then there's no output. The best position of trims still brings up quite a bit of ticking (square wave mostly). I removed the led and that only very slightly reduced the ticking noise. I don't get what causes the ticking, how does it leak into the audio path? I'll have to wait a few weeks to see of I can change optos
Not sure which link to put this in. I got my boards yesterday and started soldering the parts in that I had on hand. Everything has shipped so I should be well on my way this weekend.
I have a Fulltone Supa-Trem. I really like it but wanted to build yours for the tap tempo feature. I like the Supa-Trem because there is a blinking LED to show me the tempo at all times, even when it isn't on. Is it possible to add one to yours? If so, how and will it cause ticking?
Thanks Taylor. I am really impressed with these board, very professionally done!
I'm looking forward to getting the delay done also!
^Yes, the onboard LED displays the waveforms. Don't wire it to the switch, and just leave it hardwired to board, and you've got your tempo LED.
Wire a different LED to the bypass switch to know when it's on.
This is what I did. :)
Thankyou!! I can't wait to finsh this baby!
Quote from: Taylor on June 23, 2010, 04:05:04 PM
Here you go. I'll also add this to the PDF. Note that my way is a little different from joinpobob's suggestion. His leaves the PWM output of the TAPLFO floating when the circuit is bypassed, and while this seems to work for him, it's suppose to be bad practice to do this. In my diagram, I ground the PWM output in bypass through a 10k resistor instead of just disconnecting it.
(http://img820.imageshack.us/img820/6872/taptempotremalternateby.th.jpg) (http://img820.imageshack.us/i/taptempotremalternateby.jpg/)
I have a question about this. I want to add an LED to the 3PDT so I know when it is on or off. Joinpobob's diagram shows how to put in the LED but not tapping into the 10K resistor on the board. Where would I attach the LED to the 3PDT in this diagram so I could know when the pedal is on or off?
If you want to do what azrael suggests, then ignore that diagram and just solder the LED straight to the NEG and POS pads, and then do a normal bypass wiring like you would do with any other effect, like so:
http://generalguitargadgets.com/diagrams/switch_lo_3pdt_tb_dcjack.gif?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a
However, personally, I would (and do) wire it the way my diagram shows, and I find this preferable to having a separate flashing LED and bypass LED. But that's my preference.
I was looking to make the pedal be able to bypass, but still show me a tapped pattern. It was useful for tapping out a pattern whole it was bypassed. I did not have any problem with ticking. Jw, how would bypass like this increase chances of ticking?
Taylor, have you seen the Catalinbread Stereo Semaphore? It's a new tap tempo tremolo that has many of the same features of this circuit.
Hadn't seen it, but I knew it was on the way. It's using the same chip.
Ah, okay. Still, nice to be ahead of the curve, Eh? Hehe.
Any ideas
On my other question?
Also, never could get that multiplier step up switch to work...
It might be ambiguous from my last reply, but I have no connection to those guys.
There's nothing wrong with the way you've done it; if you want to see the speed even in bypass, that's the only way to do it. I prefer a single LED, but as I said it's just a preference. It won't create a problem with ticking.
I have my parts, but I couldn't find a 50K resistor. The closest I could find was 51K - will this be okay? The delay calls for 50K resistor(s) too.
I tried azrael's diagram for wiring it up. I got normal volume in bypass, but the bypass LED didn't light up. The tempo LED did. I have since figured out that the LED was bad. When I kicked the pedal on I got a major drop in volume. I messed with the trim pots but it didn't help. SO, I rewired it like Taylor suggested. Now all I get is loud buzzing.
I did run wires for the switch for the mulitiplyer, but I didn't order enough switches so the wires aren't hooked up to anything. Could that be the problem?
I have since ordered some more from SB. Kudos to SB - their turnaround time is much faster than it used to be! I will hopefully have them Sat.
azrael I have no idea about the ticking. I was just asking because some others have said they had problems.
Off to Radio Shack, I also forgot to order all the resistors for the delay. I thought I had some on hand.
Quote from: jcwillow777 on November 24, 2010, 11:38:34 AM
I have my parts, but I couldn't find a 50K resistor. The closest I could find was 51K - will this be okay? The delay calls for 50K resistor(s) too.
Yes, 51k is fine. Most people use 5% tolerance resistors, which means that a 50k resistor might actually measure 48k or 52k. In general, you can substitute parts like this within the tolerance of normal parts.
QuoteI tried azrael's diagram for wiring it up. I got normal volume in bypass, but the bypass LED didn't light up. The tempo LED did. I have since figured out that the LED was bad. When I kicked the pedal on I got a major drop in volume. I messed with the trim pots but it didn't help. SO, I rewired it like Taylor suggested. Now all I get is loud buzzing.
I did run wires for the switch for the mulitiplyer, but I didn't order enough switches so the wires aren't hooked up to anything. Could that be the problem?
As long as the wires are not touching or shorting against anything, they won't make a difference. If you have loud buzzing, you probably have a bad wire joint within the audio path. Use an audio probe (check the debugging links at the top of this page) to go through your audio path and see where your signal dies.
Hi guys, I am new to this forum so play nice.
I have read this from start to finish and have a few questions.
1) Does the TAPFLO chip come with the board?
How do you wire up a 9V battery and also a power source in the same circuit so only one is in use at a time, Can a LED be incorporated to show what power supply is being used.
2) How do I wire up the Gain knob, just replace the trimpot, there isnt any additional resistors or other parts?
3) If I do not want the tap through multiplier, do I just leave the EXT tabs alone, no bridging needed?
4) How do you guys ground the enclosure?
5) I have ordered some metallic caps in place of the film caps, they are the same ratings, will this be fine?
6) How do I wire up a SPDT momentary switch to be a SPST, I would think you bridge the two tabs on one side to make "one"?
I want to get everything sorted before the parts arrive, hopefully in a week so I can start building this pedal, which is going to be my first, yes I have already been told that its not a beginner pedal but I have done some electronics before and have read heaps over the last week.
Thanks in advance,
Phil
Welcome to the forum Phil. :)
Quote from: Poste on December 01, 2010, 06:27:23 PM
1) Does the TAPFLO chip come with the board?
Yes
QuoteHow do you wire up a 9V battery and also a power source in the same circuit so only one is in use at a time, Can a LED be incorporated to show what power supply is being used.
http://generalguitargadgets.com/diagrams/switch_lo_dcjack.gif?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a
Quote2) How do I wire up the Gain knob, just replace the trimpot, there isnt any additional resistors or other parts?
That's right. Electronically the trimpot acts exactly the same as a regular pot.
Quote3) If I do not want the tap through multiplier, do I just leave the EXT tabs alone, no bridging needed?
Correct, leave them alone.
Quote4) How do you guys ground the enclosure?
If you use metal jacks, connected to all the other grounds, they ground the box.
Quote5) I have ordered some metallic caps in place of the film caps, they are the same ratings, will this be fine?
Should be fine, some musicians get very mystical about cap types, personally I don't much care. Make sure they are non-polar.
Quote6) How do I wire up a SPDT momentary switch to be a SPST, I would think you bridge the two tabs on one side to make "one"?
Just leave one of the throws unconnected. Make sure you connect the pole and one throw, not 2 throws.
Taylor thanks for the fast and great reply.
I have more question now,
1)Does your circuit include short circuit protection, if not how could I do this easily/is it really required?
2) How would I wire an LED into that power curcuit to show whether batt or external power is being used?
Thanks
Phil
Sorry for the double post,
This is the film cap I swapped out for a electolytic cap
http://www.taydaelectronics.com/servlet/the-1798/1uF-100V-85C-Radial/Detail
I cant find whether it is polar or not, could someone please tell me.
Thanks
Phil
It is polar, you can tell because of the stripe which indicates negative. You can still use it, just insert them so the negative points towards the bottom of the board in both cases (the bottom being the edge which reads "tap tempo tremolo".
Yes, the 4001 diode offers protection from a wrong power supply.
Don't know a simple way to do the LED indication for battery/external, maybe somebody else has an idea?
QuoteI am getting ready to build your tremolo project and am trying to figure out which rotary switches to order for the wave form and multiplier knobs. How many poles do I need?
You only need one pole. The pole connects to where the wiper of the pot would normally go for each respective control. You need as many throws as the number of waveforms/multipliers you want. If you want them all, you need 6 throws for the multiplier and 8 for the waveform. This one will work for either, just set the position limiting washer to the proper spot:
http://www.smallbearelec.com/Detail.bok?no=477
QuoteHow many poles do I need?
I am a respectful person, which is why I managed to avoid a lightbulb joke here.
So....the pole on the rotary goes to the wiper position on the board of where the pot was. Where do the other two holes run to? The end resistors on the rotary?
They would go to the outer lugs. 5v is the leftmost pad for each pot, ground is the rightmost pad.
And just to be clear....the rotary switches are non-shorting?
Hmm... I don't think it really matters. Shorting means that the pole will connect to both throw 1 and throw 2 while it's in between positions 1 and 2. Since this is a digital input, I don't think you'll hear any discontinuity if you use a non-shorting jack. There is a lowpass filter on each pot which should smooth glitches anyway...
Yeah, I don't think it really matters.
Just got an order with a VTL5C3 and put that in, but still seem to have ticking problems. I got 2 extra NSL-32s but am yet to try them. The VTL5C3 did a little better than my first NSL-32 though. I could almost completely removed ticking but with those settings on the trims there was a massive volume drop(gain trim set to max of course). I have a 50 watt tube amp, and I would have to put volume on 12(max) to match the bypassed volume on 2.
Anyway I'll try the other NSL-32's but I'm really not sure why it's not working for me! ??? ???
What's your wiring look like? I've noticed a lot of people don't use the board-mounted pots, and have long spaghetti wiring - this is likely the cause of ticking problems in those cases. The PCB has 3 separate ground planes to keep ground currents from yanking on the audio, so with every one I've built, using board mounted pots and keeping wire runs short has made ticking not an issue.
Don't know if this applies in your situation, just something I thought worthy of note.
Yeah definitely a possibility, I have quite long wires just for the pots etc. I'll also be getting a scope soon so can have a look with that soon. Still gonna try the nsl-32s..
I have a quick question that I have not seen yet. Though there are many place to look so I may have just missed it.
Is it possible to add a momentary footswitch for nonlatching action just when you have your foot down? Would just a second 3PDT in parallel work for this?
Thanks.
You mean a momentary bypass switch that only turns on the trem when you press down?
A second 3pdt in parallel would not work, because although it would "connect the unconnected" when pressed down, it would not disconnect the connected poles. from the main 3PDT.
You could go wild and replace the switching with a logic-driven relay. It's very easy to make a logic bypass circuit that's switchable with a toggle between momentary and latching. But that whole affair would be complex.
The simplest way would be to add a toggle that routes the... uh, I'll just draw it. hang on. :)
I think this'll do what you want:
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=44108&g2_serialNumber=1
Now, the momentary switch in this case is not true bypass. You need to have the trem on, then switch your toggle to momentary mode. Now you will not hear any trem; the input is routed to the output and the PCB. Stepping on the switch disconnects the clean signal from the output and connects the trem signal.
So then my next question in the chain would be... could i use a dpdt switch to combine the switching of the toggle and spdt?
By the way thanks for the incredible work here...
No, not really. Here's why. When you turn the pedal on, you'll hear tremolo. You need the toggle to put the pedal in momentary mode, and bypass the tremolo until the momentary switch is activated. If you combined the toggle with the momentary, you would have tremolo on all the time when the effect is switched on, regardless of the position of the momentary.
Just built the pedal... everything works great, but I'm having issues with the tap tempo just like user spargo (posted a while back.) Anyone have the same issues? Anything I could do to remedy it?
Quote from: spargo on August 21, 2010, 05:23:39 PM
Sweet, adjusted the pots and set the wave distort knob to middle and it works great now! Except the tap switch seems to be pretty spasmatic? Like I'll tap it to a tempo and it just kind of randomly seems to pick a tempo...
Quote from: Moonibopper on December 28, 2010, 10:55:51 AM
Just built the pedal... everything works great, but I'm having issues with the tap tempo just like user spargo (posted a while back.) Anyone have the same issues? Anything I could do to remedy it?
Quote from: spargo on August 21, 2010, 05:23:39 PM
Sweet, adjusted the pots and set the wave distort knob to middle and it works great now! Except the tap switch seems to be pretty spasmatic? Like I'll tap it to a tempo and it just kind of randomly seems to pick a tempo...
Could be that your tap switch has pretty bad bounce, perhaps put a decoupling capacitor (10nf?) across the leads of the switch.
Also, note that the chip listens to pairs of taps. Some people are used to tap tempo where it averages all the recent taps. This one doesn't do that. If you tap three times, then tap twice, the period between your third and fourth taps will be the current tempo, but that's probably not what you were expecting.
I had the same problems when I built the first prototype, and thought something was wrong, but realized I was just tapping wrong.
Thanks for the help. If I were to tap in two different tempos (the 1st with two taps, then the 2nd with two taps - total of 4 taps), how much time needs to pass between the 2nd and 3rd tap so that the pedal doesn't think it's a continuous 4 taps?
Quote from: Taylor on December 28, 2010, 01:57:07 PM
Also, note that the chip listens to pairs of taps. Some people are used to tap tempo where it averages all the recent taps. This one doesn't do that. If you tap three times, then tap twice, the period between your third and fourth taps will be the current tempo, but that's probably not what you were expecting.
I had the same problems when I built the first prototype, and thought something was wrong, but realized I was just tapping wrong.
That's not relevant. You can tap twice to set a tempo, then immediately tap twice again to set a new tempo. The time between second and third taps can be short or long, doesn't matter.
Also, say you tap three time by accident. The tempo will be set by the first two taps. The third tap puts the chip in "listen" mode, but after a certain period of time (check the datasheet on electricdruid.net for the time - it's something like 5 seconds) the chip stops listening for the fourth tap and exits listen mode. This is good because if it didn't do this, you'd tap three times, then 10 minutes later you'd tap twice trying to reset the tempo, but you'd actually be setting the tempo for a 10 minute cycle.
It seems complicated when I describe it this way, but it's actually very simple when you get the hang of it.
Very informative. Thanks again.
Do any of the pots (I've installed all 6 as external pots) have to be set to a certain level for the tap function to work well? Particularly the speed or multiplier knob?
Also, do either of the trimmers (between the TAPLFO and OpAMP) effect the tap function depending on their setting?
Quote from: Taylor on December 28, 2010, 02:11:39 PM
That's not relevant. You can tap twice to set a tempo, then immediately tap twice again to set a new tempo. The time between second and third taps can be short or long, doesn't matter.
Also, say you tap three time by accident. The tempo will be set by the first two taps. The third tap puts the chip in "listen" mode, but after a certain period of time (check the datasheet on electricdruid.net for the time - it's something like 5 seconds) the chip stops listening for the fourth tap and exits listen mode. This is good because if it didn't do this, you'd tap three times, then 10 minutes later you'd tap twice trying to reset the tempo, but you'd actually be setting the tempo for a 10 minute cycle.
It seems complicated when I describe it this way, but it's actually very simple when you get the hang of it.
No, the pots don't effect the function of the tap. The speed knob is totally overruled when you tap in a tempo. When you adjust the speed knob it overrules the tapped tempo.
The trimpots also don't effect the tap. They are to be tweaked according to the manual to get the proper functioning in the audio section.
You might need a debounce cap on your switch as Chris says, but my guess is that (like me when I first built it) you just need to get the hang of tapping.
I just wanted to say how great this board looks! I got it in the other day and just started populating it, I'm going to end up building one for myself! Great job putting this together, and I can't wait to finish it up.
After all your help and fiddling around with the board things are working great:
1) Ticking - replaced the 330pf capacitor with a 2.2nf capacitor and the tick is completely gone.
2) Tap tempo - putting a 10nf capacitor across the SPST improved its responsiveness. I realized that if I press it fairly rapidly (rather than a slower press) it works better.
Got started on my build finally, Christmas was quite hectic and so on goes the story...
I have soldered in a few resistors, and have started to notice that the flux doesnt want to do what I would like, could someone please tell me if the flux is fine to be left as is, or should I clean it off? and if cleaning is required how would I go about it, I have acetone but have been reading that Iso Alcohol is the best way to remove it?
And could someone please tell me if my soldering is up to the mark?
Thanks in advance for any advice
(http://i277.photobucket.com/albums/kk58/fusedminis/taptempotremolo.jpg)
It should be alright to leave it. Only at very high voltages does flux residue become an issue.
But if you did want to clean it off, iso alcohol and an old toothbrush works well. My personal preference is to use an xacto knife and chip off the flux. I find that dissolving it just leaves a thin layer of flux residue on the entire board.
--Joe
Flux: if you've been using that same solder and flux with success, then you should be fine. I once bought a kind of Kester solder that - unbeknownst to me at first, had conductive flux. Be sure you don't have that.
Your soldering looks ok, but I would clip the leads much shorter than that.
I've got a quick question about board mounted pots...what would be the preferred orientation?
Like this:
(http://img.photobucket.com/albums/v298/leefordwatford/pedals/100_0011.jpg)
Or like this (which seems like it might be the "right" way):
(http://img.photobucket.com/albums/v298/leefordwatford/pedals/100_0012.jpg)
I liked the first one I built for a friend so much, I had to build a second one for myself!
I don't know, actually, because I'm not sure what the convention is for depth.
The first way, you get deeper trem towards clockwise. That might be the way people expect it to work, not sure.
Quote from: Taylor on January 24, 2011, 09:23:30 PM
I don't know, actually, because I'm not sure what the convention is for depth.
The first way, you get deeper trem towards clockwise. That might be the way people expect it to work, not sure.
I think you're right, the first way would also let it fit into a vertical 1590BB...if I measured right.
Here is a quick question,
I got this working today, however I am a little confused about the trimpots.
I brought the "gain" trimpot out to the front of the box, and I am guessing that one of the remaining two trims sets the amount of light from the led and the other brings the tick down.
But if I crank the brightness one all the way and the other all the opposite way, is this going to affect the performance of the pedal?
Thanks in advance for any info and thankyou for a great product.
Quote from: Poste on January 28, 2011, 06:49:20 AMI brought the "gain" trimpot out to the front of the box, and I am guessing that one of the remaining two trims sets the amount of light from the led and the other brings the tick down.
But if I crank the brightness one all the way and the other all the opposite way, is this going to affect the performance of the pedal?
One of the trimpots controls the brightness of the LED contained within the photocoupler, and the other controls the brightness of the LED that is visible on the outside of the enclosure. You want to set both to be as bright as possible without inducing ticking.
From the build doc:
Quote4. Setting the trimpots
The 2 trimpots in between the TAPLFO chip and the TL072 are for limiting current to the LEDs. The one directly next
to the TAPLFO limits the current to the optocoupler, and the other one limits the visible LED. Carefully setting these 2
trims will prevent ticking and give the ideal optocoupler performance as well as a tolerable LED brightness. Set them
to the position that eliminates ticking.
I would think it is more important to have the optocoupler as bright as possible, while still allowing a usable LED brightness. You just have to strike a balance between brightness and ticking. :)
Mike
Thanks mike,
At present I have the visible LED set to the brightest setting, all the way clockwise (I am guessing the trimpot is at "zero" resistance) and the trimpot for the LED in the OPTO is set to the dimmest setting, all the way anticlockwise (I am thinking full resistance)
Is this a problem, the tremolo still works, but I am wondering if I can not get more out of it.
Thanks Mike, good advice.
Basically, the brightness of the opto controls the max depth of the tremming action. If you're happy with the depth you have, it's good. If you want more depth, increase the brightness of the opto and trim back the gain to keep levels equal in effect and bypass.
Alright now I have another problem,
Hopefully the last one, I seem to be getting a quieter overall sound when using this pedal as opposed to bypass.
Can anyone give me an idea why this would be?
Thanks.
It would be because you have the opto trimpot and/or the gain too low. You've read this, right?
http://musicpcb.com/wp-content/uploads/2010/09/Tap-Tempo-Tremolo-build-PDF-updated.pdf
Thanks for the fast reply, Taylor.
This is what I guess I was asking a couple posts back about the "performance" of the pedal relating to the trimpot settings. Nowhere in your PDF does it say that a low opto trim setting will effect the output of the pedal, just thought you might want to know to maybe update it.
Or at least it is now here, so people reading this thread now has a little bit more info on setting this pedal up.
Thanks again for a quality product and the help during the build, this is my first build and I was expecting more difficult problems then this, I am wrapped with how it turned out. I will post pictures of my completed, yet ugly pedal soon.
I just reread this whole thread and found the info was already there, so sorry for reasking the same questions. I think I will have to up the 330pf to something higher I am thinking possibly the 1nf and failing that the 2.2nf.
So again sorry to keep bringing up problems that have been remedied.
No problem, these long threads are tough to navigate. Glad you got it sorted.
So, I have tried a couple of things, and still havent gotten rid of the tick.
The visible LED trim is set to full, the OPTO trim is set at about half way, there is ticking from about 1/4 turn on, and it seems that I can get the required volume at about 1/2 turn.
I have replaced the 330p with a 1n and that hasnt fixed the problem, I have replaced the OPTO, still ticks, so is there anything else anybody can provide?
I have used the alternate 3pdt wiring schematic and have also wired in the extra cable off of the 10K resistor as I thought that might help too.
Still confused, I love this pedal, but the tick has to go...
Here a really quick thought, as I dont truely understand electronics just yet, but could I just up the Gain pot to a larger figure giving me more "range" does the volume increase with the pots increased resistance or is it the other way around?
Thanks in advance for any insight
Yes, in this case, larger value equals more volume this is because the gain pot is the feedback resistor in a non-inverting amplifier (http://en.wikipedia.org/wiki/Inverting_amplifier#Non-inverting_amplifier) (r2 in the drawing there).
You can't take it as a rule in electronics that bigger pot value=more volume, because often a volume knob is a voltage divider, in which case the volume is proportional to the ratio between the 2 sides of the pot. I know you didn't ask this, but I wanted to prevent you from getting that rule in your head when it won't work most of the time.
So, if the problem is just volume, you can make the gain pot a 50k or 100k and you should have plenty of volume available. The only problem with this approach is that you're limiting the maximum depth possible, because you're amplifying not just the loud part (LED lit) but also the quiet part (which is not silent). But otherwise it's ok, and if you don't need very deep trem you should be fine.
Thanks Taylor,
I have rewired a 100K pot instead of the 20K, and am now getting the required volume, as for depth, I am pretty sure I am getting quite a bit, however I think there is more to be had, but I am a happy camper with the obtained amount,
once again thanks for all your hard work and effort in putting this together, I have had a blast building it up, I still need to get the enclosure screen printed in the near future, but everything is working great.
just a couple of quick pics of my second tremolo...the board mounted pots work great, but they made it a pain drilling the enclosure. It seemed easier to tune this one in than the last one, very little ticking. Thanks again for an awesome project!
(http://img.photobucket.com/albums/v298/leefordwatford/pedals/101_0046.jpg)
(http://img.photobucket.com/albums/v298/leefordwatford/pedals/101_0047.jpg)
Nice!
So the question was asked before but I searched everywhere and can't find the post, so I will ask it again at the risk of making my first post a flame-magnet....<shame>...sorry....</shame>
Is there a way to add a Control Voltage OUTPUT to this pedal that will reflect/mirror the tremolo wave-shape activity?
Or maybe stated another way, is there a way to construct this pedal so that it modulates a +5V signal instead of the incoming audio? AKA no longer a tremolo pedal but a control voltage generator with the same functionality?
Either way, my boards are in the mail and I can't wait to build it!!! (got one for a build-per-spec and one for devious experimentation.... hehehe)
Thanks!
Typically for CV you'd want to build a real filter to filter the PWM signal into an analog voltage as in the datasheet at electricdruid.com. This board relies on the optocoupler to do the filtering.
So I guess the way to do this would be to remove all the caps from the signal path, and remove the anti-pop resistors. I haven't done this so I can't say anything about how well it works.
OK, wow - got it. Upon closer inspection of the TAPFLO data sheet, "Application Notes: Modular Synth LFO with Tap Tempo and Ext Sync" is what I am looking for, just like you said. That will produce a 0-+5V CV generator with exactly the functionality I am looking for. COOL!
I will post some documentation on my build!!!
Thanks again!
The paint of the enclosure is drying as we speak, so here are the guts :icon_mrgreen:
(http://i69.photobucket.com/albums/i45/Valoosj/DSC03146.jpg)
Big thanks to everyone who contributed to this!
I just plugged this in and R17 (the 10 ohm resistor at the 9V input) burned up. Should I increase this value or just leave it out? My onespot runs at 9.4V.
You can just use a jumper.
It just lowers the corner frequency of the filter on the power supply, so unless you are experiencing power-supply induced humming, it's not necessary at all. :)
Mike
And it works! I don't know why the resistor burned out though. Replaced it with 100ohm.
This trem is really awesome, safe to say that it will never leave my pedalboard :icon_mrgreen:
Once I redo the decal I'll post some pics.
Question:
This has happened on a much smaller scale before, but not as big as last night.
After the tremolo is on for a while (maybe an hour or so) I get to hearing some clicking from it. If I engage it, there is a small pop. Then I turn it off again and the clicking seems to have been "drained" out of the pedal. Well, I did this the other night and there was a HUGE pop that went through the system. Almost like there was no pulldown resistor at all and there was a huge current stored up. Naturally, the tremolo was behind my delay set to a very high feedback so I unexpectedly got the pop numerous times...
Any idea what to look into for this?
I have seen this kind of issue with a lot of different circuits. Some info:
http://www.diystompboxes.com/smfforum/index.php?topic=68210.0
http://www.diystompboxes.com/smfforum/index.php?topic=23743.0
http://www.diystompboxes.com/smfforum/index.php?topic=69693.0
Really excited, just finished up soldering. Plugged it in and it worked right away, haven't noticed any issues yet. No ticking, but I haven't messed with the trimpots yet. Hopefully tomorrow I'll have time to drill out the enclosure. This is my second pedal, my first was a Big Muff clone kit from GGG which worked right off the bat too luckily. Thanks Taylor for providing the board!
Here are a couple pictures, let me know if you all see anything that needs correcting.
(http://kleinlines.com/upload/taptempo1.jpg)
(http://kleinlines.com/upload/taptempo2.jpg)
If it works and you have no ticking, then it's good. Nice job for a second project! My second was way uglier, but I didn't have such nice PCBs to work on back then. ;D
I would say that wrapping your LED wire around the in and out could potentially be a serious cause of ticking, but again if you're without it, then nothing to worry about.
QuoteI was desoldering the wave distort on my tap tempo board and goofed up kinda bad I think. I couldn't get that old wire to come out, it was really stuck. I finally got it out, but now the eyelets are missing for that contact. Is it repairable or is the board toast? It's the contact labeled "1" for the wave distort feature. Really pissed at myself grrrr
That pad just connects to ground, so you can run that wire to any other ground point in the pedal and it'll work the same.
:icon_question:
I am about to hard wire the led direct on the board and do the rewire switching Mod per Taylor's diagram to get rid of ticking in the bypass position.
I would also like to add an on/off led. Is there a way to have both mods at the same time. Does any one have a diagram or a pic of the best way to wire this.
Also i will be replacing the 330p cap to hopefully eliminate the ticking in the first 3 wave forms.
I have read about several different values from 1u to 5u to use. Does one value work better than another.
Is bigger better?
Thanks all.
With that wiring diagram, the flashing LED will turn off when you bypass the effect. So it acts as both bypass indication and speed indication, so you don't need a separate on/off LED.
Take note to use a cap between 1N and 10N, not 1u or 5u, which would be way too big. The bigger you make that cap, the more high end you will roll off, but also less chance of ticking. If you want to preserve your high end perfectly, I would recommend putting a socket in that spot and trying out caps starting at 1n and going up until you find the best compromise between ticking and high-end roll off.
The best way to avoid ticking, though, is to use board-mounted pots and keep all wires as short as possible. If you have spaghetti wiring, it will tick and all the cap stuff is just a bandaid.
Thanks Taylor for the clarification on both these issues.
I am Italian, and love spaghetti, however not in my gear, my wiring is short and tight as possible. However, I do twist my pot wire and switch wires together to make them more manageable in the box. The led wires are not twisted, however all the other wires are, could this add to the ticking?
Twisting by itself is no problem, but if you twist something carrying the LFO with something carrying an audio signal, you could have a problem. So if you twisted the LED wires with the in and out wires, for example, it could lead to ticking.
Ok Thanks
I will keep the LED wires clear and short.
Are there any other leads coming off the board that should be run with out being twisted.
I did the switching/LED mod and in doing so was able to shorten up my LED leads as well.
This cut down the ticking in the first 3 wave forms significantly. There is still a faint, but noticable tick. After the square wave it goes away 100%
I ordered up various size caps from 1u to 10u, I will try them out and let you know what value knocks out the tick.
Question on the Led brightness pot. It seams like increasing the led brightness reduces the level of the tick but all seems to "mud" up the signal.
What are the expected changes in the tone as the brightness pot is adjusted.
Is the other trim pot all gain/distortion adjustments. I am trying to understand the balance between the two trim pots and the over gain trim pot.
Thanks
Hey Ed, I want to reiterate that you want to swap the 330p with something in the 1N to 10N, NOT 1u to 10u. 1u or higher will drastically alter the sound of the pedal, removing all but the lowest frequencies. Check out this link if you're not familiar with how these values relate to each other:
http://www.justradios.com/uFnFpF.html
Regarding the trims, there really should be no change in EQ. Basically, the trimpot right next to the PIC (the 14-pin chip) controls the optocoupler, lower this resistance to get a bigger difference between quiet and soft parts of the trem. The trimpot next to it just controls the brightness of the visible LED. It should not effect sound at all. Make sure not to put it all the way at the brightest setting. The trimpot above the TL072 controls the gain, and you should just set this AFTER trimming the one next to the PIC to give you equal volume in bypass and effect modes.
yes, thank again for the clarification, it ordered the correct parts, just keep writing it wrong.
On the LED, it does seem to affect the sound of tick. When the led is brighter the tick is muffled sounding.
When it is lower it is a more defined tick sound. I assume one the cap is changed, this will not matter either?
Is this how you would wire an external gain?
(http://kleinlines.com/upload/exgain.png)
The points you've labeled 1 and 2 are connected inside the PCB, so you just need to use points 1 and 3. Looking at your pot from the front, wire them to the left most lug, and the center/wiper. It doesn't matter which goes to which.
I pulled the 330p cap and inserted a couple of sockets, I then tried, 1n, 2.2n, 3.3n, 5n,6.8n, and 10n. None of which knocked out the ticking in the square wave from. In fact for the most part I could not notice any difference in the ticking sound or volume between any of the caps I tried. I did not pay much attention to the change in tone on the guitar signal as I would like to solve the ticking first and then see if I live with how it affects the tone of the signal.
Once I dial past the square wave from, the balance of the wave forms are clear with no tick.
Is there any thing else I can try. Would replacing the opto be worth a try. Is this a characteristic that has been reported before and solved by changing the opto.
I purchased my opto from small bear and most everyone who has reviewed there stock from small bear has had no issues.
Any additional ideas would be much appreciated.
Thanks
Can you post a photo of your wiring?
Here is the wiring, the cap in the 330p position is a 2.2 it was trying.
http://gallery.me.com/edlk#gallery
Hmm. It would be better if that LED wires didn't run over the audio portion of the board (right side). I think at this point you'll need to try to adjust the trims differently unless you're willing to rebuild it using onboard pots. Try lowering the visible LED all the way, turn the gain to the middle, and adjust the trim next to the PIC until the ticking is tamed.
Are you using 22k trimpots and gain pot (would have to be 25k for the gain pot)?
The trim pots are 22 K the gain pot is 25 K
I originally had the led wires around the board but shortened them as advised in earlier posts.
This was done simultaneously with the cap changes.
Is there any merit in re routing them around the board.
I think I have every combination of trim pot and gain settings.
The one thing consistent is that the tick is does not change in sound or volume with any of the adjustments.
And as previously stated the cap value in the 330p location has not affect from 1n to 10n
If were any other form other than the square form, I would live with it, however this wave form is the one I use the most.
I'm game for any suggestions
If the trimpots really have no effect on ticking, and a 10n cap doesn't, that's very weird. 10n should totally choke it at the expense of a lot of high end. I will try to ponder what could be happening in your build and get back later.
let me clarify
The caps do not affect the tick in any noticeable way. the guitar signal tone was affected.
If I roll the led pot to full bright, the tick does "muffle" a bit, however the volume of the muffled tick is the same.
Ed
Found this in another thread, http://www.diystompboxes.com/smfforum/index.php?topic=90425.0. As Taylor has eluded to, your build technique may be what is causing the ticking. This person ended up needing to screen the PCB from the jacks to eliminate ticking. I'd be tempted to pull the circuit/pots/jacks from the box and start moving stuff around to see what, if anything, is coupling to cause the tick.
THanks for lead,
My next move will be to pull everything out of the enclosure and see if screening parts from the board make any difference.
Ok, here is what I have tried so far
I tried a different led, that made no difference
I pulled the led out of the holder and moved it around the enclosure and straight up in the air, that made no difference.
As suggested above, I pulled everything out of the enclosure and laid it on the bench, out of the enclosure I got the same tick in the on the same first three wave forms, strongest in the square form, and was a bit louder.
It did seam that touching the led wires affected the tick, making it louder?
I have a 2.2 cap in the 330p position.
Is this symptomatic of a bad opto?
Am I at the point where I need to rip all the pots off and install on board pots
Any other opinions or suggestions would be welcomed.
Thanks Ed
Another opto might be a good thing to try. The pot wires don't make a huge difference really - they don't carry the LFO signal, so I don't think they would cause the really noticeable problem you're having. Sorry you're having so much trouble Ed! This hobby's supposed to be fun, not frustrating. :-\ Try a couple other optos and see how it goes. Allied electronics has them cheaper than anybody else.
Just in the process of building one myself. How about making my own opto? I have a bunch of random LDRs, and my LED/LDR combo seemed to work great in my Trem Lune. Is there a particular LED type to use?
I used Futurlec # photocell1, and Mouser # 593-VAOL-5LAE2 (100mcd red diffused) when I built my pic trem (http://www.diystompboxes.com/smfforum/index.php?topic=77471), which is closely related to this. It worked really well.
It is my understanding most photocells respond best to yellow. One datasheet that I have (for the Tayda Cds photocells) specifies the peak spectral response as being between 550 and 650nm... yellow.
Mike
Hey Taylor
I sent for a couple of new opto's from Steve Daniels. I put one in the on the board today.
I can knock out the tick if I crank the led to full on. However the last bid of rotation on the led pot seems to take out a bit of my high's
I currently have a 2.2 cap in the 330 p position. Would lowering that cap value help with the loss of high's with the led cracked full on.
Does the led pot even affect the frequencies? Or am I getting a bit "blurry" trying to debug this tick?
Thanks Ed
one other observation, it seems like most of the guys who have not had any issues with ticking have not used the external gain pot?
Could there be a connection between the ticking and the use of the external gain pot as apposed to the board mounted trim pot?
Quote from: EDLK on March 26, 2011, 12:59:05 PM
one other observation, it seems like most of the guys who have not had any issues with ticking have not used the external gain pot?
Could there be a connection between the ticking and the use of the external gain pot as apposed to the board mounted trim pot?
Potentially - that pot is in the makeup gain stage's feedback loop. If those wires went over the LFO side of the board, or were right next to the LED wires, the LEd could couple into the audio path. The LED pot shouldn't really affect the frequency response.
Also, wanted to let everybody know that Small Bear is now stocking the crystal needed for this project:
http://www.smallbearelec.com/Detail.bok?no=1128
ok
I pulled the 25 K external pot and installed the trimmer pot
no change in the tick in the first 3 wave forms
In an earlier post you mentioned that we should not put the led trimmer pot to full on. This is the only position where the tick is changed to more of a muffled pop.
I am going to try doing the onboard pots next.
Ed
Quote from: EDLK on March 26, 2011, 04:18:30 PM
In an earlier post you mentioned that we should not put the led trimmer pot to full on.
Did I say that? Doesn't sound right, but sometimes I do post here when I've just woken up or should be going to bed and my brain is not fully spun up.
I don't think you should put either LED trim all the way up. This will draw more current and I would expect this to mean more ticking.
Quote from: Taylor on March 26, 2011, 03:19:41 PM
Also, wanted to let everybody know that Small Bear is now stocking the crystal needed for this project:
Http://www.smallbearelec.com/Detail.bok?no=1128
Something seems to keep URL-hacking your Small Bear links.
Uh, yeah, what the heck?
http://www.smallbearelec.com/Detail.bok?no=1128
Oh, I get it. The auto-parse code will add http:// to any url that starts with a capital letter. For some reason SB links start with a capital H in my browser.
Ok
I believe I have attempted everything suggested on this forum to this point so I will not relist them
The last attempt was going with on board pots, i changed then all out.
I un twisted every other wire lead coming off the board and made them all as short possible.
Each and every attempt as yielded the same ticking in the first three wave forms
The only place where I can eliminate the ticking is with the LED pot full on, and this affects the high frequency tone.
Am I at the end of the line as far as suggestions go?
Thanks for hanging in with me on this
Ed
Quote from: Taylor on March 26, 2011, 04:55:48 PM
Uh, yeah, what the heck?
http://www.smallbearelec.com/Detail.bok?no=1128
Oh, I get it. The auto-parse code will add http:// to any url that starts with a capital letter. For some reason SB links start with a capital H in my browser.
It's neat Taylor, Steve added in text that says "for Taylor Livingston's Tap Tempo Tremolo"
Jacob
I just finished putting the circuit back into the enclosure after pulling it to de bug the tick
I tried on board pots, various cap sizes in the 330p position, swapped out the opto.
Tried the on board gain trim pot vs. off board 25K pot.
Rewired the every connection to be sure nothing crossed paths with the led or lfo signal carrying wires.
And now not only do I still have the ticking in the first three wave forms, I also have a buzz in the signal path.
Anyone have any Idea what I could have done to bring that on?
Not having sufficient electrical circuit knowledge, I believe I have reached my maximum debugging capabilities on this.
I would be happy now just to get rid of this new buzz which makes the pedal unplayable, and live with the ticking.
>:(
Any one willing to take this one on, I would greatly appreciate some help.
Ed
Buzz usually means some grounding problem. Check that when you rewired things, you didn't fray the ground wires of the input and output jacks, etc.
Anyone else encountering problems getting the tap to work right? When I tap to set the tempo, it seems like the tempo is taking the tempo from the re-opening of the switch contact instead of closing. So I tap the switch, but the up swing of the tempo seems to be in between my taps, if that makes sense. When I use a tap tempo, I expect the signal to be at the top of the wave form for each tap, but it seems it is operating the opposite. Thoughts?
What kind of switch are you using? You're sure it's a normally open type?
yep, normally open. i'm wondering about the debounce network, because also sometimes the tempo will jump up to about a million times faster than my tap when I'm tapping out the tempo. Which components on the board make up the debounce network?
Debouncing is done in software. What sort of switch do you have?
This one
http://www.pedalpartsplus.com/mm5/merchant.mvc?Screen=PROD&Store_Code=PPP&Product_Code=9014&Category_Code=SWI (http://www.pedalpartsplus.com/mm5/merchant.mvc?Screen=PROD&Store_Code=PPP&Product_Code=9014&Category_Code=SWI)
as far as i can tell it's the same one smallbear and mammoth sell. But I also tried swapping it with some known momentary NO switches I had, including some from an old MXR footboard and some push buttons from radio shack. Same result.
Hmm, strange. That's the same type I'm using and haven't experienced that. As you can see in the schematic, the tap switch connects directly to the PIC, with just a resistor pull-up. So I can't think of any error in your build that could be causing it.
From TTG's page on debouncing (http://tech.thetonegod.com/debounce/debounce.html), the simplest thing to try would be a cap across the switch terminals, but this probably won't help much. The logic debouncing is pretty simple and would do a much better job. That would be what I'd try.
Did you just build this up, or have you had this issue for a while? I only ask because I have built quite a few of these and only had that problem at first because it was my first tap tempo effect, and I didn't have the hang of tapping solidly. I don't in any way mean to impugn your tapping skillz, just wanted to mention that as a possible place to look if you hadn't yet. It might be a total non-issue, but just trying to help.
Quote from: Taylor on March 28, 2011, 08:34:46 PM
Hmm, strange. That's the same type I'm using and haven't experienced that. As you can see in the schematic, the tap switch connects directly to the PIC, with just a resistor pull-up. So I can't think of any error in your build that could be causing it.
From TTG's page on debouncing (http://tech.thetonegod.com/debounce/debounce.html), the simplest thing to try would be a cap across the switch terminals, but this probably won't help much. The logic debouncing is pretty simple and would do a much better job. That would be what I'd try.
Did you just build this up, or have you had this issue for a while? I only ask because I have built quite a few of these and only had that problem at first because it was my first tap tempo effect, and I didn't have the hang of tapping solidly. I don't in any way mean to impugn your tapping skillz, just wanted to mention that as a possible place to look if you hadn't yet. It might be a total non-issue, but just trying to help.
No offense taken! I've actually built two of these, and the first was the same way. I chalked it up to the LED not charging up and down fast enough to accurately indicate the tempo. But this one is way more defined an issue than the first one.
So, after executing what I thought was a super-clean build, I fire up the freshly completed Tap Tempo Tremolo and.....nothing. No LED, no effect, zero. So begins troubleshooting. Everything looks OK!!! Optocoupler in right (ie side with "dot" is facing the two trimpots...that is correct, right?)....power, ground appears OK....bypass switch ok.....all knobs set north/middle....what gives.
So after looking REAL close, I realize that my TL072CP is actually a TL022CP. My order was for a 072, and the bag it came out of was labeled 072, but the top of the chip says 022 (you can actually read it in one of the high res photos). Looking at the data sheets they appear to have the same pin assignments, but (slightly) different operating properties....
So could this incorrect op-amp cause the thing to not work at all?
Symptoms:
I hear the signal when pedal is bypassed, I hear the signal when pedal is on. No tremolo or LED though.
FYI, the two outer jacks are the audio in and out, and the two inner jacks are a CV in for multiplier, and clock out from Pin 7 of the TAPFLO. Those two inner jacks are hooked up with a single wire each that goes from the tip lug of the jack to the respective point in the circuit in a "piggyback" fashion. So for instance, the multiplier knob is a PCB mount pot, and I connected the CV wire to the center leg.
Also, all the jacks are pretty close to each other and to the pots below but I have made absolutely certain they are not touching each other or anything else and they are lock-washered snug and not going anywhere.
Here are some build pics:
(http://farm6.static.flickr.com/5061/5597246531_c324bcedf8_z.jpg)
high res here:
http://www.flickr.com/photos/jasonandlindy/5597246531/ (http://www.flickr.com/photos/jasonandlindy/5597246531/)
(http://farm6.static.flickr.com/5028/5597246371_85e396ec98_z.jpg)
high res here:
http://www.flickr.com/photos/jasonandlindy/5597246371/ (http://www.flickr.com/photos/jasonandlindy/5597246371/)
Thanks for any help!
Alright, so you get bypass and you get sound through the effect, but no tremolo.
Since you're getting sound through, it is not the opamp. The audio path and the LFO are, for all practical purposes, independent.
The dot on the NSL-32 indicates the negative side, so the way you have it oriented should be correct as well (Taylor can confirm this).
The one thing that stands out to me as being something to check is the resistor for the Wave Distort. Looking at the resistor that you soldered there, it looks like Brown-Black-Black-Orange-Brown-- 100k. It is supposed to be 10k-- Brown-Black-Black-Red-Brown.
I think that would set the wave distort all the way to one side-- in this case the dark side-- and make it so that the LED just can't turn on. And since the LED can't turn on, the signal goes straight through with no change in volume.
That's the first thing I would check. :)
Mike
WOW! Good eye. I did indeed have a 100K in the wave distort spot instead of a 10K. Swapped that out, but it is still doing the same thing. Only now when the effect is engaged there is a "volume swell" from silent to less quiet than the bypassed signal. The swell occurs over about 1 second, and then the volume stays at the "less quiet level" without any modulation. Bummer. Still no LED.
If I had the LED wired backwards would that possibly result in the symptoms I am experiencing? I am pretty sure I wired it correctly but I don't have any way to check without dissassembling and redoing it.
Thanks,
Quote from: turunturun on April 07, 2011, 11:14:01 AM
WOW! Good eye. I did indeed have a 100K in the wave distort spot instead of a 10K. Swapped that out, but it is still doing the same thing. Only now when the effect is engaged there is a "volume swell" from silent to less quiet than the bypassed signal. The swell occurs over about 1 second, and then the volume stays at the "less quiet level" without any modulation. Bummer. Still no LED.
So the sound drops out, and then fades back in (but quieter) when you engage the effect? Odd. Well, at least the right resistor is in there now-- a step in the right direction! :)
QuoteIf I had the LED wired backwards would that possibly result in the symptoms I am experiencing? I am pretty sure I wired it correctly but I don't have any way to check without dissassembling and redoing it.
If we assume the NSL-32 is oriented correctly (and it should be, according to the datasheet and the PCB silk screen), you can at least check that the external LED is wired properly without removing it. The cathode (negative) terminal should have a flat spot on it, like this (http://images.myfilehost.us/images/arx1226197078y.png).
Mike
Yeah - thanks for the help Mike. (PS Hi from Atlanta!).
So unfortunately I positioned the LED under the circuit board and with PCB mounted pots....I will have to take everything out of the box in order to remove the PCB, in order to take a look at the LED.
A thought just occurred to me. Couldn't I test the LED as a diode with a multimeter's probes on the right parts of the circuit to confirm orientation? Lets give that a try....
As a side note for next time, I might get things working OUTSIDE the box on my next build, then stuff it all in there...! :icon_rolleyes:!!
Tested the LED as a diode with my multimeter and its in there correctly (it even lit up with the multimeters current! who knew?!).
So it sounds like a botched job on the waveform distort knob pins could lead to the issue I am having? (ie accidentally reversed 1 & 2 or something???).
Or not?
Well, the only reason I suspected the LED was oriented wrong is because you seemed unsure. When you're unsure, double-checking is in order. ;)
I think it's time to grab your multimeter, and take some voltages. The procedure is listed here (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0).
In particular, make sure you get voltages on the PIC. :)
Mike
Are you positive you have the opto in right? It's important not only that the dot side face toward the trimpots, but that you get the resistor side (long legs) in on the "east" side (facing the trimpot above the TL072) and the LED side of the opto in on the PIC side of the board.
I don't know if the labeling of all NSL-32s follows a convention or is random, but if yours is like the ones I have here, then you have it in wrong. Looking at the ones I've built, if I oriented the "32" the way it is in your photo, it would put the resistor side of the opto on the left, and the LED on the right, which would be incorrect.
Hmmm, I snipped the leads, so can't tell which is the long lead side. Seems like it should be possible to test it while its in the circuit tho, right? Like use the diode feature on a DMM and find out which side is the diode side?
Right, that should work. Also, the LED side's leads are flattened, and the resistor side's leads are round in cross section. I'm looking at your hi res photo and it looks to me like you have the LED side in the resistor pads and vice versa.
So now would be a good time for me to find a good tutorial on the best way to desolder a PCB. Every time I try it I lift a trace or ruin a pad or both.....( :icon_sad: game over, man!!!!).
Thanks a for taking a look Taylor....who knew? I thought you could just stuff that 32 bug in there and cover it with solder.
To desolder; yank the wire out with pliers while melting the solder. :)
Indeed, but make certain that both the top and bottom sides of the pad are molten before pulling. Most of the problems I see people having with desoldering double-sided boards happen because people flow one side of the joint, but don't wait for the top side to melt, then they rip out the plated through hole.
Get a healthy amount of solder on your tip before flowing the joint. A desoldering braid or pump is cheap and helps quite a bit.
Thanks for the tips! That is what I have been doing in fact, but to sufficiently wick the solder out enough to reopen the hole I end up burning the pad and making it too cooked to accept solder. Or at least that is how I have ruined a couple PCB's. I have built a couple amps with good success....I figured pedals would/should be easier!?!? I think the TTT has been a bit more difficult than the Spitfire clone I am building from scratch right now also....!!!! (not really....doing heater wires is a PITA).
Seriously tho, it is fun building the effects and the work that the DIY community has put into generating these incredible full-featured circuits and chips is amazing.
Thanks!
Hmm, well that's part of the reason I prefer a solder pump to wick - never have any issue pulling pads. But I know others swear by wick/braid, so different strokes and all that.
That makes sense regarding the pump. I never found it useful, but then I was trying it on amp sized components and cables where a fair amount of solder was involved. But the pump seems to make a lot more sense on a circuit board. Thanks!
Looked close, and yup....my LED and resistors are reversed. Bummer. It just seems like the 32 looked so good the way it was.... :icon_biggrin: Time to play "operation". hehehe.
Long time reader, first time poster. I just finished my build (pic below) - everything works great except for, like Ed, the ticking on some waveforms. On my build its the first and third ones that make the ticking - ramp up and square. It's very not noticeable when playing, but when muting the strings it's definitely there. I'm running an external volume pot that runs near the wave selector but not near the PIC. Cables are only as long as they need to be.
I can get rid of the ticking by cranking the trimpot near the PIC, but then the gain pot can't go about 9 o'clock without the pedal pumping out a waaaay too loud signal. Besides diming the trimpot, any other setting yields exactly the same ticking level when adjusted for gain. There also seems to be a loss in dynamics with the trimpot cranked, so currently I've got it set so I have unity gain when the Gain knob is at 12 oclock.
(http://the-controls.com/files/trem.jpg)
OK - after having a mess with my build I've found a fix for my ticking issue. First I disconnected the LED to see that had any effect. Immediately the ticking disappeared. Next I tried messing with some resistors and found that I could remove the ticking by connecting a 10k resistor between ground and the positive LED pin. This dims the LED a bit and makes the LED trimpot more responsive - I can dial out the ticking while still having the LED blinking bright enough. All good so far. :icon_smile:
Here are some debug readings for my TTT
Battery Terminal with new battery:
Pos: +8.9
Neg: 0
Circuit Boards 9V in:
Pos: +8.9
Neg: 0
TL072 (which is actually a TL022 b/c I haven't received the 72 yet...they appear similar in function per data sheet):
1: +4.2
2: +4.2
3: +4.2
4: 0
5: +4.2
6: +4.2
7: +4.2
8: +8.5
TAPFLO:
1: +5.0
2: +2.2
3: +2.3
4: +5.0 (drops to 0 when tap button is pressed)
5: +2.5 (stays steady...I would think this should be fluctuating???)
6: 0
7: 0 to 5 (voltage fluctuates pretty squarely and tracks the tempo that has been tapped in via button)
8: 0
9: 0 to 5 (appears to track movement of wave distort knob correctly)
10: 0
11: 0
12: 0
13: 0
14: 0
Wave Distort Pot:
1: 0
2: 0-5
3: +5
All other Pots:
1: 0
2: 0
3: 0
So it appears that only the wave distort knob is getting +5V on pin 1. From there it looks like it is supposed to go to the 10K resistor, then to Pin 3 of the Tempo knob. Since I don't get anything on P3 of the tempo pot I measured resistance from the "north" leg of the 10K resistor to P3 tempo and got 12K ohms or something....I looked over the solder joints and they all appear good, and the trace doesn't look damaged. Not sure why it would be reading out resistance.
Pretty self explanatory there mate. Something's grounding out your pots.
The resistor next to the wave distort pads is not involved in the wave distort function - they both connect to 5v but their functioning is independent, so don't worry about that.
If your pots' 5v connection was getting grounded, we'd expect the 5v connection of the wave distort pot to be the same. Can you post a pic of your build, or tell us how you've wired the pots?
Taylor, I finally finished up mine and I just wanted to say what a great design and great pedal. I never thought the day would come that my Tremulus Lune would be pushed off of my board, but this pedal has finally done it. Everything I ever wanted in a Tremolo. Here's the pics of my build:
(http://i865.photobucket.com/albums/ab217/twt_fx/IMGP1819.jpg)
(http://i865.photobucket.com/albums/ab217/twt_fx/IMGP1822.jpg)
Hats off to you sir and keep up the great work.
Great build! Nice clean job.
Thanks. This is truly a great pedal and I'm hoping to get some clips recorded soon that I can share.
I just completed my 2nd full build of this circuit. After not be able to debug The first build trying everything suggested and previously tried to get rid of the ticking in the first three wave forms. I started from scratch, new board, new components, nothing reused from the first build. I have yielded the same results. You can see from my previous posts all that was tried on the first build.
The only new symptom and effect I can add is that with the led disconnected the tick in the first three wave forms is half as loud as with the led connected.
Needless to say I am getting close to bringing the pedal out to the driveway and running it over with my truck.
If not for the tap tempo ability of this circuit, Which is what makes this trem unique , I would have had my tantrum long ago.
I am out of ideas, anyone who is willing to take this on would be my hero.
Ed
Sorry you're having so much trouble Ed. This might be something to try:
http://www.diystompboxes.com/smfforum/index.php?topic=84020.msg774688#msg774688
I did try this, it did not reduce the ticking any more than when the led was diconnected.
Does it still tick with the guitar disconnected from the input? (bridge the ground switching on the input jack if you use that)
The ticking might represent transients in changing the amplitude of noise going INTO the pedal, rather than any inherent problem.
I will give anything a try at this point however I have tested it in several location a nd different amps. As well as different power supplies and batteries. The tick is only in the firs three wave forms and non existent in the others.
Tested with just a jack in the input to switch the unit on the tick is the same as when played through the complete rig
I played around with the led and wire leads coming off the board to the led.
With the LEd disconnected the tick drops in volume by about 75%
Even with the wire leads disconnected from the led, if you put the ends in close proximity to one another the ticking comes back up in volume.
The farther you spread the ends of the leads the more the volume of the tick drops out?
I tried the 10 k resistor from ground to the pos. side of the led. and could not notice any change in the tick.
Perhaps I am not placing it correctly?
The tl072 and the tapflo are the only two components reused from the last build.
Could the problem reside in either of those?
Ed
This may be a beginners question. I've beautifully soldered everything to teh PCB. I also connected the 3PDT as well as the momentary switches. My question is about the input/output jacks. The diagram (update with LED hard wired directly to the board not the 3PDT) shows 1 wire going to each from the 3PDT. I have the mono jacks with 2 terminals on each. What goes on the other terminals? Is it a ground? I noticed on some of the completed pics in this thread that it appears the input jack has 2 wires going to it and the output jack only 1 wire. Also I am uncertain if the wires off the 3PDT are supposed to go to the tip or the ring terminal on the jack.
I am anxious to plug this thing in and see if it works. I just don't want to fry anything out by wiring in the jacks wrong. I'm a bit of a newbie. If anyone can clear this up for me it'd be great. Thanks.
Yes, that wiring doesn't show the ground, since it's kind of assumed that you've built some pedals before this one. It's really not a good first project.
The wires shown from the switch to the jack go to the tip of the jacks. Connect the sleeves and the ground wire from the 3pdt switch to the ground tab of your power jack.
there are some great off board wiring diagrams available at Tonepad.com
Thanks for the clarification. I am an aircraft electrician by trade so I am quite familiar with electronics although I am fairly new to the DIY Pedal market. I built 2 pedals years ago and decided to try this one. With the help of the posts in this thread I'm confident I can weed out any issues that I may run into once I fire it up. Thanks again.
I've just been doing a whole heap of breadboarding using the taplfo and i think I may have a cure for ticking! So putting a 10uf* cap inbetween the base and emitter(or gnd) of the transistor completely removed my ticking. I don't know why this really works, when I first heard the ticking i was like hmm.. lets try putting caps in places that may help and this seems to do the trick.
I get absolutely no ticking with my amp on 10 before if i turned it up to 5 or 6 it would be insanely loud with ticks. At the moment i'm doing my trem passive so when i actually finish this thing up we'll see if it's really a cure... Also it doesn't alter the waveform as far as I can tell too. When I made this on the square wave I never got it quite right, I'll test it on my actual board soon..
* (i'm using 22u used 3.3u and you could still hear a little ticking so 10u+ should be okay i think)
what type of cap are you using, film or electrolytic?
Thanks Ed
I'm using an electrolytic (+ve to base) , but I tried this on taylors board and it didn't help that much :icon_neutral:, even though what I have on the breadboard is basically the same deal. It might be worth a try still, i'll post back later when i give it a better go.
I tried a 10 u and 22 U on the Tr1
It did cut the ticking by 60-70%, however, it did not knock it out of the signal
Also it flattened out the the 2nd and 6th wave forms to a point they would be un-usable.
What type of Opto are you using, where did you purchase it. I have been using the nsl-32 from small bear
i'm using a homemade one ~500k off 10k on roughly the same as the nsl-32. Double check you have it on the emitter and not the collector. If you put it on the collector you'll lose a lot of depth. (you could try a small cap collector to ground but this will mess with your depth.)
So on the 2nd and 6th waveforms, how do they become unusable? It doesn't seem to be affecting the waveforms at all for me. Also a larger than 22u cap may help you, but if it's messing with your waveforms it'll probably make that worse.
I will try again and make sure I have it on the emitter
On the 2nd and 6th waves it flattens the out to where you can nearly tell they are on.
I will try again and make sure I have it on the emitter
On the 2nd and 6th waves it flattens the out to where you can nearly tell they are on.
I confirmed I had the cap in the correct position
I did try 10 and22 u they worked about the same
Perhaps I am not getting the same results because my tick is very loud to start with
Firstly, thanks to everyone involved in designing this and to Taylor for the pcb and Molten Voltage for the chip.
Just finished building it (pics in pics thread) and I love it!
I used an LM9314 to drive LEDs for the waveform rotary knob. I found a handy calculator to help set it up and I'll post details tomorrow when I'm on my pc and not my phone.
I've had a couple of issues though. Firstly I put the TL072 in backwards (actually soldered the socket in backwards and used that to orientate the chip)....school boy error! Sorted that no probs, had to replace the 10r resistor near the diode and replaced chip.
I then noticed that the pad for the 5v supply on the multiplier pot was only giving out 2.89V. Any idea why? I just piggy backed the 5v from another pot so not really a problem.
The problem that's got me stumped is the multiplier rotary pot. I can't select the last 2 settings using the pot. When I go to the 5th setting I get a 1/4 note (I think) instead of the 8th note triplets and the same for the 16th note setting.
I've checked the voltages going to the chip and they appear fine. They are 0.38, 1.21, 2.04, 2.87, 3.70 and 4.54V.
The strange thing is that I can get the triplets and 16ths if I use the multiplier switch to step through the settings.
Did I damage the chip with the reversed TL072 or something?
Any pointers would be greatly appreciated.
Jimi
The multiplier's positive pad is supposed to be limited like that. The reason has to do with the code, and I'll explain that below if you're interested. Notice that the multiplier's positive pad is fed not by 5v, but by a resistor connected to 5v. So you thought that was wrong, but it was right, and when you attempted to fix it, you caused the problem you're having with the multiplier.
So nothing's broken, just solder the multiplier pot where it's supposed to go and your problem will be solved. :)
-------
The reason it's like this: in the code, the pot is used as a rotary selector. The code masks off the pot's value until it is a 3-bit number, which gives 8 possible values. Since only 6 were needed, the code is set to give x1 multiplication for the last 2 values, and the resistor is used on the positive lug of the pot to limit the range of the pot to about 0-3v, so you should never get to the last 2 positions.
Awesome build BTW!
Oh my god! What an idiot! I looked at the TapLFO datasheet and followed the diagram for the Waveform Rotary and then applied that to the Multiplier. It says 'The top two options are not used for the Multiplier.' but doesn't mention the fact its not being fed by 5V as the Waveform rotary is and needs a 3k6 resistor to drop the voltage. Maybe I should look at the schematic a bit closer next time. I should've really put 2 and 2 together. I'll connect it to its proper pad tomorrow.
Thanks for the help Taylor, its a great pedal and a great PCB. The service you offer is amazing. The time you spend answering questions is unbelievable and I wish there were more people out there offering the kind of customer service/care that you do.
I've got an Echobase PCB waiting to be boxed up, I cant wait!
Thanks again,
Jimi
Hi,
Taylor, sorry to bother you again but I've swapped the feeds of the Multiplier roatry pot to their proper places and for some reason I'm now getting 4.64V on the +ve rather than the 2.89V I was getting before. I've checked the 3K6 resistor and swapped it for another. I'm getting 4.93V before the rersistor and then 4.64V after the resistor and on the pot pad. Any ideas whats going on now?
I've been asked to explain how I set up the LM9314 for use with the Waveform Rotary Pot.
I really am still a newb at this electronics lark so I've probably missed something obvious here but it works for me!
After breadboarding a few things whilst looking at the datasheet and app notes I was struggling to get it calibrated right. I turned to google for some help and stumbled across a handy little calculator.
http://www.electro-tech-online.com/blogs/ericgibbs/136-dual-lm3914-v3-0-calculator.html (http://www.electro-tech-online.com/blogs/ericgibbs/136-dual-lm3914-v3-0-calculator.html)
I still struggled to get it perfect as the calculator didnt seem to like the fact that the voltages on the rotary pot were in steps of 0.6V but the first position was at 0.36V and not 0.6V. Therefore if you calibrated it to 0.6V stages the first LED wouldn't light up because the voltage handn't reached the turn on voltage of 0.6V.
I found that if you swapped the 5k resistors from the 5V and 0V feeds to the pot to 10K it increased the voltage on position 1 to 0.58V. I then used the calculator to calibrate the chip for 0.58V steps and I'd cracked it!
So... on the LM3914 I ended up with pins 2 & 4 connected to ground, pin 3 connected to 9V+, 5 connected to the output of the rotary pot, 6 & 7 tied together, a 4K7 resistor between 7 & 8 and a 13K8 (or 10K + 3K8 in series) from 8 to ground. 9 was left open to keep it in dot mode where just one LED lights at a time. I used 9V to power the LED's with a 4K7 (I think thats what I settled on) resistor to tame them a bit.
I still had a problem because the first LED was always very dimly lit whatever the position. I got a PM from .Mike who suggested placing a 10K resistor across the first LED. Bobs your uncle....problem cured. Apparently it does mention it somewhere in the datasheet but I missed it.
Hope it may help somebody.
Cheers,
Jimi
Thanks for the info on how you setup the 3914. :)
Mike
Quote from: Jimi W on April 30, 2011, 03:12:41 PM
Hi,
Taylor, sorry to bother you again but I've swapped the feeds of the Multiplier roatry pot to their proper places and for some reason I'm now getting 4.64V on the +ve rather than the 2.89V I was getting before. I've checked the 3K6 resistor and swapped it for another. I'm getting 4.93V before the rersistor and then 4.64V after the resistor and on the pot pad. Any ideas whats going on now?
It probably has to do with the fact that you're sort of mixing my circuit with Tom's diagram. My advice earlier actually forgot to take into account your rotary wiring, sorry about that.
Tom's diagram shows an 8-position switch, but you should only use a 6-position (the switch can be set for 6p using the inner washer most likely). Forget the 3k6, and put a 25k resistor from the sixth position of the rotary to 5v. It sounds to me like you've got the rotary set up as an 8-position.
Cheers Taylor for the quick response.
I am using a 6 position switch and I have a 5k resistor going from 5V to position 6 as shown in Tom's diagram. So should I either take this 5K out and replace with a 25K (or just add a 20K in series) or do I add the 25K to the existing 5K?
I guess the confusion is coming from combining your PCB with Tom's diagram, combined with my lack of knowledge to put 2 and 2 together!
Cheers for the help,
Jimi
I'm guessing the 25k is to replace the 5k from the 5V to the rotary switch and the 2 10k's that would be between the extra 2 positions that are missing?
Jimi
[explanation in black; quick answer in red]
Well, Tom's diagram actually shows what I'm talking about, but it might be confusing.
If you look at the diagram, which is for the waveform switch with 8 waveforms, you see that it says, "the top two options are not used for multiplier". But you should still treat the resistor chain as if those last 2 switch positions were there - you just won't ever select them. So you need to maintain R1, R2, and R3 in order for the resistor chain to form the proper voltage divider. Since they are 3 resistors in series, we can combine them - two 10k's and a 5k equal 25k total. This 25k resistor acts as those three top resistors would if the top two positions were never used. By taking out the two 10k's, you've changed the division ratio of the whole divider (the rotary switch is acting like a pot wired as a voltage divider).
Note that in a voltage divider, the total resistance doesn't matter - only the ratio between what's on one side of the pot's wiper/switch's pole and what's on the other side. That's why, on the board we use 10k pots and a 3k6 resistor, whereas in Tom's diagram, the total resistance is 80k, and it works the same.
Replace your 5k from the top switch position to 5v with a 25k resistor. :)
Hi Taylor,
Thanks for the reply. I actually understand the long explanation in terms of the voltage divider. Alarm bells did ring when you mentioned a 25K resistor and it dawned on me I would've altered the total resistance of the chain and therefore the voltage divider.
Its working perfectly now and my wife and baby have been out this morning so I've given it a good play through a cranked amp. Great pedal. I really like the multiplier footswitch. I think it would be really useful in a live situation and allow a bit more creativity without needing to tweak knobs. Shame I'm not in a band anymore!
I'd be even better if I could get the status LE D's of the multiplier Rotary switch to change as I stepped through as a visual reference. Is the stepping through done completely within the chip and is there no way to get the voltage and use it to drive a LM3914? I've measured the voltage on the multiplier pin (pin 11 if I remember rightly) and it doesn't change when your step through the multipliers. I'm guessing its not possible.
Cheers,
Jim
Quote from: Jimi W on May 01, 2011, 08:23:01 AM
I'd be even better if I could get the status LE D's of the multiplier Rotary switch to change as I stepped through as a visual reference. Is the stepping through done completely within the chip and is there no way to get the voltage and use it to drive a LM3914? I've measured the voltage on the multiplier pin (pin 11 if I remember rightly) and it doesn't change when your step through the multipliers. I'm guessing its not possible.
Cheers,
Jim
Hmm... I don't think it's possible that way, but it's fairly simple logic to have a button press cycle through a set of LEDs. That's not my area, so offhand I'm not sure what logic IC you'd want. I guess a Johnson counter? You'd then need to make the multiplier switch a DPDT momentary, and use the second pole to drive your counter logic.
You'd need some way of deciding whether the rotary switch or the footswitch controlled the LED counter. You're looking at another PIC there.
Hmm, I'm using a DPDT momentary at the minute because thats all I had in the way of momentary switches so thats cool but thats the least of the issues really!
I could add a second set of LED's. I'd then have the original LED showing what the original multiplier position was (as well as the actual knob!) and the second set showing the stepped through multiplier position.....or maybe a Bi-colour LED (depending whether both circuits used the anode as the common source for the LED's) then the LED could light the second colour when the footswitch was used.
Hides-His-Eyes - any idea on what IC would be ideal for such a job, I've had a quick look for Johnson counters but the datasheets dont really show a simple circuit like i'd want where a voltage pulse would trigger the next output (sorry if these terms aren't correct!)
Cheers guys,
Jimi
If you only had the switch, you could probably do it using a CD4017, that will step through up to 10 outputs each time it's clocked. There's no easy way to integrate a logic based method with the pot so that it will start counting from where ever the pot is set.
Can someone give me a good recommendation for a switch for the tap tempo? The one I have now is very finicky and doesn't seem to lock in well with my taps. It seems to not recognize some and sometimes tapping at 60bpm produces a 6000bpm result (exaggerating... but only a little). Should it be a normally open switch? Supplier and part number would be appreciated.
Thanks!
Quote from: Geosh on May 05, 2011, 02:11:14 PM
Can someone give me a good recommendation for a switch for the tap tempo? The one I have now is very finicky and doesn't seem to lock in well with my taps. It seems to not recognize some and sometimes tapping at 60bpm produces a 6000bpm result (exaggerating... but only a little). Should it be a normally open switch? Supplier and part number would be appreciated.
Thanks!
Mine does that occasionally. It's a debounce issue I can't seem to track down. It's rare enough it never bothers me though.
A big thank you to all those involved in designing this amazing pedal.
(http://i297.photobucket.com/albums/mm227/ValoosjFX/DSC03185.jpg)
(http://i297.photobucket.com/albums/mm227/ValoosjFX/DSC03188.jpg)
Quote from: Barcode80 on May 05, 2011, 06:09:11 PM
Quote from: Geosh on May 05, 2011, 02:11:14 PM
Can someone give me a good recommendation for a switch for the tap tempo? The one I have now is very finicky and doesn't seem to lock in well with my taps. It seems to not recognize some and sometimes tapping at 60bpm produces a 6000bpm result (exaggerating... but only a little). Should it be a normally open switch? Supplier and part number would be appreciated.
Thanks!
Mine does that occasionally. It's a debounce issue I can't seem to track down. It's rare enough it never bothers me though.
Put a small value capacitor across the tap switch terminals, maybe 10-100nF. The debounce is done in code but may be finicky for switches with extremely long bounce.
If that doesn't help then a new switch is a good solution. Yes, it should be a normally open switch. I can't suggest a good switch, I haven't had experience with many. Maybe someone who has a large stock of different switches can do a bounce-time shootout?
Quote from: Jimi W on May 01, 2011, 08:23:01 AM
Hi Taylor,
Thanks for the reply. I actually understand the long explanation in terms of the voltage divider. Alarm bells did ring when you mentioned a 25K resistor and it dawned on me I would've altered the total resistance of the chain and therefore the voltage divider.
Its working perfectly now and my wife and baby have been out this morning so I've given it a good play through a cranked amp. Great pedal. I really like the multiplier footswitch. I think it would be really useful in a live situation and allow a bit more creativity without needing to tweak knobs. Shame I'm not in a band anymore!
I'd be even better if I could get the status LE D's of the multiplier Rotary switch to change as I stepped through as a visual reference. Is the stepping through done completely within the chip and is there no way to get the voltage and use it to drive a LM3914? I've measured the voltage on the multiplier pin (pin 11 if I remember rightly) and it doesn't change when your step through the multipliers. I'm guessing its not possible.
Cheers,
Jim
Yes stepping is done in code, no outputs from the chip currently have any information on that particular setting. Sorry, that part of the code was organized as a "theres an extra pin on the chip, let's try to put something in!" kind of deal. A johnson counter would not work well because it would go out of sync all the time, with the way the code works.
EDIT: Well, there is a way but it would be pretty complicated. It involves using the multiplier pin voltage as a reference and a weighted johnson counter to incrementally add to the voltage input to the LM3914 you are using. :icon_rolleyes:
Would there be no problems if I used one of these:
(http://www.getlofi.com/wp-content/uploads/2008/05/stereo_jack.jpg)
connected the Tempo pot to the three lugs, and then let the pot be disconnected when there was a stereo cable plugged, allowing an expression pedal to be used in place of the Rate/Tempo control?
Any idea, Taylor, when these might be back in stock?
Gabriel
I'm not sure if anyone ever made a demo of this pedal, so here's mine :D
Sounds good Yorick but I'm very interested in the sine wave sound and I missed that in your demo.
Could you perhaps tape a small part with that sound , would be really great !
Tia,
Alf ( from Holland !)
Quote from: G. Hoffman on May 17, 2011, 06:42:09 PM
Any idea, Taylor, when these might be back in stock?
Gabriel
Hi Gabriel, the tap tempo tremolo (http://musicpcb.com/pcbs/tap-tempo-tremolo/) PCB is back in stock as of today.
Quote from: alfafalfa on June 07, 2011, 01:21:51 PM
Sounds good Yorick but I'm very interested in the sine wave sound and I missed that in your demo.
Could you perhaps tape a small part with that sound , would be really great !
Tia,
Alf ( from Holland !)
From 3:40 all the way til the end it is on sine wave.
Thanks, you're right of course but what I really mean is a part where what you play is in sync with the tremelo speed.
I'm looking for an old fashioned slow sinus tremelo sound. My tremulous lune sounds okay but it hasn't what I'm after.
"That's the way" from Venice is the sound I'm looking for.
Since a few days ago I am no longer able to select a waveform. The pedal worked just fine before. I opened it up and measured 7,5V at my 78L05. Is it safe to assume that it is busted and in need of replacement? I had a chance to measure the one which I made for a friend, and there I had 6V at the 78L05. That pedal works fine.
Should I search for a better supplier for the 78L05, or is this normal?
Is there anything I can do to prevent blowing this transistor?
According to the datasheet on the 78L05, if you feed it 7-20 volts and pull a current of 1-40 mA, the output should be between 4.75 and 5.25 volts. I just don't see any circumstances where the tap tempo tremolo circuit would exceed the input voltage or current draw.
I'd say something is up with either your regulators, or your builds.
When I was breadboarding the TAPLFO a couple of months ago, I swear had some regulators whose pinouts were opposite of what it shows in the datasheet. In particular, I think they were 5v regulators from Tayda, but I'm not sure. They put out well over 5v until I turned them around.
Grab your breadboard, a regulator, and your multimeter. Make sure you have them oriented correctly. :)
Mike
I'll give that a go then. Hopefully this is the case as it would be an easy fix.
The 7805 and 78L05 are opposite pinouts IIRC, that tripped me up a few times. I don't know if that's adding to the confusion.
That's what I missed, I just had a butcher's at my layout and the pinout is incorrect there. Thanks for clearing this up guys. Would have found it out, but haven't had the chance to look at the pinout and such.
Yesterday was a good day.
Amongst other things, I finished the TTT. It's fantastic !! Worked first time, no ticking and a really versatile effect. I would suggest having an external gain pot to anyone thinking about building it. It can get a bit quiet with narrow pulse widths.
Pics to come soon.
Thanks Taylor !!
hey guys, got a bit of an issue here. With the waveform knob, I'm not getting a random waveform at the end of the taper. the effect just shuts off. thoughts?
got a bit of ticking, dialed it out, but the level seems kind of low. might have to change the gain trimpot so I can get it up to line level!
When you say it shuts off, do you mean your signal comes through unaffected or the signal cuts out?
Signal cuts out, pulsing LED turns off.
Also sometimes the tap function is weird and oscillates. :(
What voltage is the waveform pot putting out at the end of the taper?
Just finished mine (no box, but working). It sounds great to me, as everything sounds like it's working. No ticking, even with the trimpots turned up. I used a 2.2nF in place of the 330pF, and used an NSL-32. The tap function is awesome!! I'm batting 3-0 with Taylor's projects!
Quote from: .Mike on July 15, 2011, 10:08:37 PM
What voltage is the waveform pot putting out at the end of the taper?
Itt's kind of hard to tell. All i know is that the taper of the waveform pot pretty different from the last Tremolo I built, that one had no problems.
The only parts substitution I made was a 470pF cap instead of 330pF. :( Oh, and I "made" a 3.6k resistor with two 1.8K.
So the first one I built the guy wants some changes to...
How would I go about taking out the rate knob? Just Jumper across it? Or can I just leave it out entirely?
Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.
Basically I need to dumb it down a to the Depth knob, sine/square(or maybe triangle) switch, & quarter/eighth switch (I think, not really sure yet). Oh, and add an external jack for tap tempo.
Quote from: lwatford on July 17, 2011, 06:17:22 PM
So the first one I built the guy wants some changes to...
How would I go about taking out the rate knob? Just Jumper across it? Or can I just leave it out entirely?
Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.
Basically I need to dumb it down a to the Depth knob, sine/square(or maybe triangle) switch, & quarter/eighth switch (I think, not really sure yet). Oh, and add an external jack for tap tempo.
So taking the rate knob out works great, are there any issues that could happen doing it that way?
I'll try switches next...
Quote from: lwatford on July 17, 2011, 06:37:30 PM
Quote from: lwatford on July 17, 2011, 06:17:22 PM
So the first one I built the guy wants some changes to...
How would I go about taking out the rate knob? Just Jumper across it? Or can I just leave it out entirely?
Is it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.
Basically I need to dumb it down a to the Depth knob, sine/square(or maybe triangle) switch, & quarter/eighth switch (I think, not really sure yet). Oh, and add an external jack for tap tempo.
so my first attempt at switching didn't work...I'm not sure I quite understand what is being done with the control voltage and the multiple switch.
So taking the rate knob out works great, are there any issues that could happen doing it that way?
I'll try switches next...
Quote from: lwatford on July 17, 2011, 06:37:30 PMSo taking the rate knob out works great, are there any issues that could happen doing it that way?
I'm not sure of the consequences of removing the tempo knob. If I recall correctly, when I was putting together the non-tap version of this, Tom (who designed the LFO) told me that you shouldn't leave any unused CV pins floating.
I'm not sure how this applies to the tap tempo version of the LFO, though, since the tempo CV is overridden with the tap value.
Either way, the solution is easy: put a jumper between the middle pin of where the tempo knob was, and the pin that connected to ground.
Quote from: lwatford on July 17, 2011, 06:17:22 PMIs it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.
Totally possible.
Page 8 of the LFO Datasheet (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf) will help you do this. It shows hot to replace both the waveform and multiplier selectors with rotary switches.
You need to use this diagram to work out a voltage divider to connect to your switches. For example, if you wanted the 2nd and 7th waveforms, you would setup something like this:
|5v---\/\/\/15k\/\/\/---|---\/\/\/50k\/\/\/---|---\/\/\/15k\/\/\/---Gnd|
Use an SPDT toggle, and connect the middle lug of your switch to where the middle lug of the pot you removed was connected. Connect one lug of the switch to where the first 15k and 50k meet (waveform #2), and the other lug to where the 50k and the second 15k meet (waveform #7).
I hope that helps. :)
Mike
thanks for the help! I got the two waves I want, going to work on the multiplier next. Will it be any different because of the two unused positions?
Quote from: .Mike on July 18, 2011, 08:29:50 PM
Quote from: lwatford on July 17, 2011, 06:37:30 PMSo taking the rate knob out works great, are there any issues that could happen doing it that way?
I'm not sure of the consequences of removing the tempo knob. If I recall correctly, when I was putting together the non-tap version of this, Tom (who designed the LFO) told me that you shouldn't leave any unused CV pins floating.
I'm not sure how this applies to the tap tempo version of the LFO, though, since the tempo CV is overridden with the tap value.
Either way, the solution is easy: put a jumper between the middle pin of where the tempo knob was, and the pin that connected to ground.
Quote from: lwatford on July 17, 2011, 06:17:22 PMIs it possible to do have two waveforms and multipliers on switches rather than on pots? I assume just find the resistance for the ones you want and use resistors, but I'm just curious how you would do it.
Totally possible.
Page 8 of the LFO Datasheet (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf) will help you do this. It shows hot to replace both the waveform and multiplier selectors with rotary switches.
You need to use this diagram to work out a voltage divider to connect to your switches. For example, if you wanted the 2nd and 7th waveforms, you would setup something like this:
|5v---\/\/\/15k\/\/\/---|---\/\/\/50k\/\/\/---|---\/\/\/15k\/\/\/---Gnd|
Use an SPDT toggle, and connect the middle lug of your switch to where the middle lug of the pot you removed was connected. Connect one lug of the switch to where the first 15k and 50k meet (waveform #2), and the other lug to where the 50k and the second 15k meet (waveform #7).
I hope that helps. :)
Mike
Quote from: lwatford on July 18, 2011, 09:45:52 PM
thanks for the help! I got the two waves I want, going to work on the multiplier next. Will it be any different because of the two unused positions?
Yeah, check out the datasheet again... "The top two options are not used for the Multiplier."
You still have to account for the resistance of the top two positions-- just like you would with the waveform-- it's just that there are only six possible multiplier settings.
And btw, I had the reference to the two waveforms reversed in my last post... should be:
Connect one lug of the switch to where the first 15k and 50k meet (waveform #7), and the other lug to where the 50k and the second 15k meet (waveform #2).
Mike
that's what I thought, just wanted to double check! Thanks again!
Quote from: .Mike on July 18, 2011, 10:20:09 PM
Quote from: lwatford on July 18, 2011, 09:45:52 PM
thanks for the help! I got the two waves I want, going to work on the multiplier next. Will it be any different because of the two unused positions?
Yeah, check out the datasheet again... "The top two options are not used for the Multiplier."
You still have to account for the resistance of the top two positions-- just like you would with the waveform-- it's just that there are only six possible multiplier settings.
And btw, I had the reference to the two waveforms reversed in my last post... should be:
Connect one lug of the switch to where the first 15k and 50k meet (waveform #7), and the other lug to where the 50k and the second 15k meet (waveform #2).
Mike
Quote from: azrael on July 15, 2011, 03:08:34 PM
hey guys, got a bit of an issue here. With the waveform knob, I'm not getting a random waveform at the end of the taper. the effect just shuts off. thoughts?
got a bit of ticking, dialed it out, but the level seems kind of low. might have to change the gain trimpot so I can get it up to line level!
Any more ideas on this?
What do you mean when you say you can't tell what voltage is coming out of the pot's wiper when set to random?
Wow. Eff me! I went over the whole offboard wiring and circuit with a multimeter, I had the freakin' waveform pot hooked up wrong! mixed up legs 2 and 1. :icon_redface:
works fine now. :D
;D Glad it got sorted.
Thanks for the help!!
I got the switch working, but decided to just put in a rotary switch for the multiplier...cause I knew if I didn't, I would end up doing it later! Picky people! It's now a nice mess inside, but I don't know how to make it much better. The way the box is drilled isn't ideal, but since his kids did it up when it had something else in it, I can't really change it out.
I'm going to change the tap tempo switch to one of the soft touch ones that other people have been using, they seem lots better than the xwing one that's in there.
So here it is:
(http://img.photobucket.com/albums/v298/leefordwatford/pedals/Photo-0068.jpg)
and just because...here's mine:
(http://img.photobucket.com/albums/v298/leefordwatford/pedals/101_0046.jpg)
Hello!
I'm very interested in building the circuit. I want to make 2 pedals and connect them in series in order to make some interesting effects, for example, setting one really slow with a light depth and then the other really fast with a heavy depth. I want to synchronize one tempo from another pedal. Using multiplier feature it's possible to make fast from slow and slow from fast. Pin 7 of the chip provides clock output.
First question: how can I get clock input?
Second: is there a way to make fine adjustment of the tempo which is provided by another pedal? Setting both tremolos to speeds that are close but different will also make some interesting effects.
Third: is there a way to move starting phase of the wave?
Thanks.
Any comments would be very appreciated. For the diagrams can't even ask.
Quote from: telebiker on July 20, 2011, 01:40:12 PMFirst question: how can I get clock input?
I don't think you can. The easiest way, though, is to use on rate CV, and use it for both LFOs. That will sync them.
Quote from: telebiker on July 20, 2011, 01:40:12 PMSecond: is there a way to make fine adjustment of the tempo which is provided by another pedal? Setting both tremolos to speeds that are close but different will also make some interesting effects.
Not an easy, built-in way, no.
Quote from: telebiker on July 20, 2011, 01:40:12 PMThird: is there a way to move starting phase of the wave?
Not without editing the code, no.
Mike
Thanks.
I think I will use one tap-tempo in for both LFO's (not one rate pot), seems doable. That will sync them too, right? As for speeds that are close but different, I think, I will be satisfied with two individual rate pots. Tell me please if I'm saying a rubbish. :)
Wave moving would be so useful for building a stereo tremolo. :)
All sounds sensible.
If you tap the tap switch a single time, it resets the wave phase to the time you tapped. If I understand what you're trying to do, this would do it, although not perhaps with as much control as you want. You can have your two trems going in sync, then hit the tap switch on one one them when the other is in the off phase of the cycle, to get panning.
Quote from: Taylor on July 20, 2011, 02:44:25 PM
If you tap the tap switch a single time, it resets the wave phase to the time you tapped. If I understand what you're trying to do, this would do it, although not perhaps with as much control as you want. You can have your two trems going in sync, then hit the tap switch on one one them when the other is in the off phase of the cycle, to get panning.
That's great idea, but how can I combine two tap tempo inputs at one LFO?
Here's mine :
(http://i15.photobucket.com/albums/a400/Used666_/IMGP3705.jpg)
(http://i15.photobucket.com/albums/a400/Used666_/IMGP3706.jpg)
I need to redo the switch wiring as I'm getting the bypass tick but other than that it's great
Anyone have experience (either actual or theoretical) with CV implementation in this pedal?
So after rebuilding the PCB with a new one I got my TTT working - it works pretty much perfect in stock config.
However, I installed a CV input jack for the division/multiplier and that works also.....but adds a ferocious audio pop whenever the voltage changes.
I am using a Moog MP201 to send a square wave voltage between two settings and on each "edge" of the wave there is a pop. It only happens when the mp201 is sending voltage. If the voltage is off, but the cable still connects the devices its quiet.
My method for wiring up the jack was to connect the tip lug to the center wiper of the division knob. The build guide made no mention of what to do with the sleeve connection on the jack so I didn't connect that to anything.
So the build guide mentioned adding a resistor in series with the CV connections to "limit current" but I didn't do that....could that be causing it?
Any other ideas?
Here is a video of the issue that may help:
http://youtu.be/ArLF7KAXp-A (http://youtu.be/ArLF7KAXp-A)
And here are the build pics (from before I replaced the circuit board with the new one, but everything else stayed the same)
(http://farm6.static.flickr.com/5061/5597246531_c324bcedf8_z.jpg)
high res here:
http://www.flickr.com/photos/jasonandlindy/5597246531/ (http://www.flickr.com/photos/jasonandlindy/5597246531/)
(http://farm6.static.flickr.com/5028/5597246371_85e396ec98_z.jpg)
high res here:
http://www.flickr.com/photos/jasonandlindy/5597246371/ (http://www.flickr.com/photos/jasonandlindy/5597246371/)
Having a strange issue. When I completed the tremolo, I tested it on a breadboard and it was dead quiet with no ticking. Now that it's in an enclosure, I'm getting significant ticking on some waveforms. The annoying thing is that it's doing it even in bypass. I've tried redoing my wiring as well as disconnecting the LED but nothing changes. Anyone have the same issue?
Check out the first four pages of this thread for a lot of relevant info and a diagram.
Thanks Taylor, totally missed that. :D ;D
Well, I used the correct wiring scheme and messed around with the trimpots some more. I believe I have the tick completely dialed out, plus it has lots of gain.
Cool, glad to hear it. It can be tricky to dial in, but it's quite possible to build this with no ticking. I spent a lot of extra time with this PCB layout, doing overkill measures to keep grounds separate and all that for that reason.
is this board http://musicpcb.com/pcbs/tap-tempo-tremolo/ - capable of being the modular LFO Synth? - http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf
need to get 1 or 2 of this one with my 2 echo base when i order soon... thanks!
Quote from: wizardsofzen on August 30, 2011, 01:28:34 AM
is this board http://musicpcb.com/pcbs/tap-tempo-tremolo/ - capable of being the modular LFO Synth? - http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf
I would have to say no, not directly.
This project uses the interaction between an LED and a (slow) LDR to filter the LFO, and uses the LDR to vary the gain of an opamp.
The modular synth LFO from the datasheet uses a series of filters and amplifiers (and a bipolar power supply) to output a clean +/-5V LFO.
You would have to build everything that is connected to pin 5 on a separate board, including the power supply that is not shown.
Mike
thanks for that! time to perfboard then
So, I built a TTT months ago and have been using it regularly. But the other day, all of the sudden the LED started going bonkers. It blinks supper fast for about a second, then off for a second, then repeats - kind of like the lights on a cop car. It doesn't seem to be very related to the current speed/waveform. The trem itself still seems to work fine though. Any ideas?
Honestly, I can't figure out what could possibly be happening there. You're saying that it flashes the same no matter what speed and waveform you set?
The indicator LED and the LED half of the of the optocoupler are both driven by the same transistor. So, since the tremolo is working fine, you can deduce that the transistor is driving the optocoupler as expected, and so the transistor is probably working fine.
The problem most likely has to lie somewhere after the transistor. Maybe the LED somehow got fried, or there is an intermittent solder joint.
Mike
Quote from: Taylor on September 11, 2011, 02:58:59 AM
Honestly, I can't figure out what could possibly be happening there. You're saying that it flashes the same no matter what speed and waveform you set?
Mostly yes...there may be a very slight change in how long/short if pauses for, but in general it's the quick flashes, pause, then more quick flashes no matter what the settings are. I will take another look at it and see what I can find.
Anybody have luck with ticking on this build?
I've adjusted the trim pots to kingdom come, but still have ticking both when the pedal is engaged AND in bypass... I have wired a regular bypass LED in addition to an always-on rate LED. Even if I turn the LED's trim pot so far down that the LED is off I get the ticking. The opto's trim pot is also all the way down and I can still hear it.
It's definitely possible to tune out any ticking, which should be minimal anyway.
What type of opto you are using, have you tried a different one in its place, and what type of LEDs you are using for indication?
Check the areas that handle power filtering to make sure you don't have any cold solder joints. Try increasing C9 to 1n.
:)
Mike
Quote from: .Mike on September 26, 2011, 10:19:34 PM
It's definitely possible to tune out any ticking, which should be minimal anyway.
What type of opto you are using, have you tried a different one in its place, and what type of LEDs you are using for indication?
Check the areas that handle power filtering to make sure you don't have any cold solder joints. Try increasing C9 to 1n.
:)
Mike
I'm using the Silonex NSL-32 from Smallbear, and uh...regular LED's? Your standard 5mm. On regular LED for bypass and one connected to the board for indication. Soldering is fine. I've tried increasing C9 to 2.2uF and I *think* it helped a bit when the pedal was on, but with the pedal off the ticking was just as bad.
The reason I asked about the LED is because standard LEDs use a lot more current for the same brightness. For example, the standard LEDs I bought in bulk from Tayda take the full 20 mA to equal the brightness that I achieve on a quality non-superbright red LED at about 2 mA. If you have two or three LEDs running at 10-15 mA each, and you add in the ~20mA the PIC takes (IIRC from when I was hacking together the non-tap version of this), you could be trying to pull 65 mA through that poor little 78L05 regulator. The more current you pull, the higher the chance of noise.
Of course, since it still ticks when the LED current is very low, and since it is ticking when it is bypassed, that suggests there is error in your build. There haven't been many reports of people with that problem that I remember, but you may want to go back and see if someone else had (and fixed) the same problem. Also, the audio path to this is the same as the Trem Lune, so a lot of the debugging information that is out there applies to this as well. :)
Mike
Quote from: .Mike on September 27, 2011, 09:32:18 PM
The reason I asked about the LED is because standard LEDs use a lot more current for the same brightness. For example, the standard LEDs I bought in bulk from Tayda take the full 20 mA to equal the brightness that I achieve on a quality non-superbright red LED at about 2 mA. If you have two or three LEDs running at 10-15 mA each, and you add in the ~20mA the PIC takes (IIRC from when I was hacking together the non-tap version of this), you could be trying to pull 65 mA through that poor little 78L05 regulator. The more current you pull, the higher the chance of noise.
Of course, since it still ticks when the LED current is very low, and since it is ticking when it is bypassed, that suggests there is error in your build. There haven't been many reports of people with that problem that I remember, but you may want to go back and see if someone else had (and fixed) the same problem. Also, the audio path to this is the same as the Trem Lune, so a lot of the debugging information that is out there applies to this as well. :)
Mike
Can I ask where you get "high quality" LEDs that get the same brightness for 10 times less current? I'm using ~5-8000mcd LEDs. And thanks for the trem lune info, will look into it...
I should also note my waveform LED is coming off the board and thus through the LM78L05 regulator, but the second bypass LED is running straight from the 9V source.
Well, the difference I was pointing out is between "standard" LEDs, which datasheets indicate put out single-digit MCD levels, compared to, for example, one like this (http://www.mouser.com/ProductDetail/VCC/VAOL-5LAE2/?qs=io7aH2hdVh4zu26pEAxQtg%3d%3d), which is not high efficiency or high brightness (100mcd), but certainly puts out the same amount of light at 2mA as a standard LED.
That's the LED I used in my build for indication and for the optocoupler. When I was debugging, switching from LEDs out of the bulk bag of standards to LEDs that were more efficient, and upping the cap I mentioned earlier, completely eliminated the ticking I experienced. I attributed that to the fact that I was able to measure the same resistance from the photocell with less than a fifth the amount of current. I went from using something like 30mA of current for the two LEDs to something closer to 5mA, a huge difference.
Maybe Taylor can chime in if he remembers from when he was designing this, but if upping that capacitor from 330p to 2.2u didn't stop the ticking, it would again suggest a mistake in your build. Most people, it seems, settle on 1n in that position. :)
Mike
I'm working on a TTT at the moment, and my tap switch did not appear to be working. On further investigation, I found that ultimately my 78L05 is getting an input of roughly 8.8v and sending that same 8.8v right out the other side. Would it appear this one is faulty? Oddly enough, the trem works fine, minus the tap switch.
Disregard...it seems that somehow either Eagle flipped the part the wrong way or I got 78L05's with a reversed pinout. The Fairchild Semi ones I got ended up being put in backwards...
I just found this project while I was eyeing the Meatsphere project over at Musicpcb, and I don't think I can express how stoked I am to build this!
Short history (and partial reason why). I've been a guitar player at churches for over 10 years now (geez has it been that long?!?!), and one thing you'll find at a lot of churches is that they like to keep the guitar player "under wraps" using direct in type effects such as the Line 6 pod setup. So, I had one, and while I found most of it's modulation and time based effects AWESOME, there was a serious lack in tone (especially distortions) YMMV tone is subjective, not a debate against Multieffects. Fast forward a couple years, playing at different church with a sound guy/worship pastor who is all about tone. I'm now playing with a tube amp/pedalboard mic'd etc etc. The only downside is I've never been able to find a tremolo that was as versatile as the one on my Pod XT in stompbox forum. I have Line 6's Tap Tremolo pedal now, which works OK, but it doesn't have any kind of Time Signature/Multiplier feature, or near the options that this project has.
Needless to say I will be building this project, and putting the Line 6 pedal up on the 'bay. That is, once I get my workstation a bit more "clear" :icon_redface:
Hope this post isn't too far off track. Just wanted to give kudos to the builders/designers/contributors of this project from a guy that will get a lot of real world use out of it ;D
God bless,
-Kevin
Okay so i finally got around to building my tap tremolo last night. bypass works fine, but when the effect is engaged i just get an ossilating sound. all the knobs work because the oscilating pulses and the led flashes but no guitar signal is passing through with it. Any Idea at all what this could be? I'm still pretty new to the pedal building game, I've built 5 or 6 BYOC kits so I thought I could take the leap to this. Appartently I suck at it. Help me!
Hi Kyle,
If you've got the LFO going, you have the most complex part of the circuit working, so that's good.
The first thing to do is to make sure there isn't a simple mistake. Make sure the vactrol is mounted the right way. Make sure the opamp is inserted in the right direction. Make sure you used the right component values in the right places. Make sure the trimpot for the vactrol is set somewhere in the middle. Otherwise, it might be that the LED side of the vactrol is turned all the way off.
If that doesn't work (and it probably won't), it's time to take some voltages. Here (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0) is the debugging topic, which will walk you through it. Since the opamp is the only active component in the signal path, the voltages for it are the most important.
If the problem isn't obvious after posting voltages, the next step will probably be to make an audio probe. You can then figure out where the signal stops, and debug whatever problem exists after that point.
:)
Mike
How do i go about making an audio probe?
http://www.diystompboxes.com/pedals/debug.html
http://www.geofex.com/FX_images/audioprb.gif
Ok I have a couple questions. Im still new to pedal building so they are sorta noobish. Some that have probably already been asked but I didnt really see the so Ill ask again :P.
1) If I wanted to add the multiplier spst switch what exactly does it do? Is it the same as the multiplier pot? (I feel really dumb for askin this one lol)
2) For the waveform and multiplier pots, how many people use a rotary switch? Is using a rotary switch better than using a pot? If it is better to use how do I go about doing it? I was a little confused as to how to do it when I was looking at the diagram.
3) How can I add a second LED so that I have one for showing when it is bypassed and one that stays on that blinks with the tempo?
Thanks for helping and sorry for the noobish probably really obvious questions...
1) If I wanted to add the multiplier spst switch what exactly does it do? Is it the same as the multiplier pot? (I feel really dumb for askin this one lol)
It cycles through the multiplier, overriding the value set by the pot.
2) For the waveform and multiplier pots, how many people use a rotary switch? Is using a rotary switch better than using a pot? If it is better to use how do I go about doing it? I was a little confused as to how to do it when I was looking at the diagram.
Most people use pots because they are cheap and easy. That makes it slightly less obvious which waveform you have selected, but it's still pretty obvious when you have switched waveforms. Wiring up a rotary switch is more complicated, since you have to basically solder 2 resistors to every lug on the switch. The rotary switch setup is covered briefly in the Taplfo's (http://www.electricdruid.net/index.php?page=projects.taplfo) datasheet.
3) How can I add a second LED so that I have one for showing when it is bypassed and one that stays on that blinks with the tempo?
Basically, the board has a spot to hook up an LED for indication. If you want that LED to always be flashing, regardless of whether the pedal is in bypass, then just hook up an LED. Your status indicator LED would hook up to your 3PDT just like any other pedal. If, however, you want the flashing LED to only appear when the effect is engaged, I think there is certain technique that works best. It is covered earlier in this topic (sorry, I don't know where).
:)
Mike
Quote from: .Mike on October 31, 2011, 03:43:29 PM3) How can I add a second LED so that I have one for showing when it is bypassed and one that stays on that blinks with the tempo?
Basically, the board has a spot to hook up an LED for indication. If you want that LED to always be flashing, regardless of whether the pedal is in bypass, then just hook up an LED. Your status indicator LED would hook up to your 3PDT just like any other pedal. If, however, you want the flashing LED to only appear when the effect is engaged, I think there is certain technique that works best. It is covered earlier in this topic (sorry, I don't know where).
:)
Mike
Ok so just stick the one led in the area on the PCB where it says LED Negative & Positive and the setup the other led the way the off board wiring shows on Tonepad? Oh and the other question I had was what is the control voltage?
Quote from: Ultrakd on October 31, 2011, 04:39:03 PM
Ok so just stick the one led in the area on the PCB where it says LED Negative & Positive and the setup the other led the way the off board wiring shows on Tonepad?
Yes, that's right.
QuoteOh and the other question I had was what is the control voltage?
I don't understand this question - could you say it in a different way? Are you just wondering what control voltage is in a general sense, or something to do with this project?
Quote from: Taylor on October 31, 2011, 04:54:50 PM
QuoteOh and the other question I had was what is the control voltage?
I don't understand this question - could you say it in a different way? Are you just wondering what control voltage is in a general sense, or something to do with this project?
Yes pretty much in general. But also in this project, under the modifications section. It says "Any pot can be modded for CV (control voltage) input easily."
Well, Google can find you all you'd need to know about CV, but the basic idea is that you have a varying voltage, and that voltage controls some parameter. In this pedal, all five standard controls are changed by a varying voltage between 0v and 3.3v (actually less than that for the multiplier knob).
This isn't generally of much interest within a standard effects pedal setup because you need other CV circuits to do anything with it. But it's useful for synth people who have other modules that create varying voltages based on a variety of factors. It's really only useful when you have multiple separate units which can either create or accept or modify control voltages. Read up on modular synthesizers to get an idea.
For somebody with only pedals, most of which they didn't build, CV isn't something that's of much use.
But for example, if you had an envelope follower CV module, you could plug your guitar in there, and get a CV that changes with the playing dynamics, so you could change the speed of the tremolo by playing harder or softer for example.
oh ok I under stand some better now...thanks :P
Is there a way to make stereo output so I can plug it into 2 amps?
If you just want to split your mono signal to two amps, you'd want to build a buffered splitter - plenty of schematics for that online. If you want to pan back and forth or apply tremolo to a stereo signal, you'd need to add another the optocoupler and duplicate the whole audio path of the circuit.
For panning, you'd also need to invert the control signal - this is tricky since the the control signal enters the optocoupler as a PWM signal, not an analog voltage. You'd need to filter the PWM into analog CV. So this is somewhat more advanced, and the relevant info is in the datasheet for the TAPLFO on electricdruid.net if you want to dive into it.
Quote from: Taylor on October 31, 2011, 10:55:00 PMFor panning, you'd also need to invert the control signal - this is tricky since the the control signal enters the optocoupler as a PWM signal, not an analog voltage.
If I remember right, it is really easy to invert the action of the LED with no extra components. I just don't remember exactly how.
I
think that instead of connecting the LED anode to +5V and letting the LFO vary the voltage above ground where the cathode sits, you connect the cathode directly to ground, and let the LFO vary the voltage to the anode. Something like what is shown here (http://www.diystompboxes.com/smfforum/index.php?topic=29374).
I'd have to breadboard it to be sure, but it's really simple. :)
Mike
D'oh, you're right Mike. I did that in my fake phaser project a while ago; don't know why that slipped my mind.
I suppose there's a possibility that this could make the trimmers harder to set w.r.t. ticking, but that may not be an issue at all.
Ok this is what I was meaning something like this pedal does. http://www.youtube.com/watch?v=73K-9ErZroQ
Just ordered my TTT board and chip from Taylor :icon_biggrin:. I have quite a few projects to finish before I start on it (that is if I can keep myself on track lol). I'll update my progress once I get there.
-Kevin
What would be the best size enclosure for putting this pedal in? Having 3 footswitches...
Question, Getting ready to build a TTT. The BOM indicates 22K trim pots and the board looks like it should have 10K trimmers. Please help?
They're used as the current limiting resistors for adjusting the maximum brightness for the LED and the vactrol. Anything from probably 5k on up will work well. It's not going to change the sound at all.
The bigger the value, the dimmer you will be able to get the LED. By dimming the LED, you decrease the chance of ticking. For most LEDs, 10k will work. I suspect Taylor suggests 22k because some really high efficiency LEDs might still able to be dimmed further than 10k.
Mike
What would be the best size enclosure for putting this pedal in? Having 3 footswitches...
For my Bob Terwilliger-sized feet, I can't stomp 3 switches in anything smaller than a 1790ns probably. But if I were you I'd just lay out the switch on a box in various setups and see what feels comfortable to you.
ok yea I got big feet to lol. thanks for the help cant wait to start building the pedal.
How do you add expression jacks for the multiplier and speed?
i was looking around and just didn't see where the A25K Pot goes for Gain?
also is there a link anywhere that has all those input like LFO and everything else like the first pictures in this post?
i got the whole board plugged up, waiting on me to put in wires ... thanks!
All the documentation is at the website in my signature.
The pot would replace the trimpot above the opamp.
Adding expression jacks is like adding them for any pedal - I think there should be diagrams out there. You just use a switching jack to either have the pot or the expression pot connected. The wiring will be different depending on how your expression pedal is made.
Hey I cant find any 22k timpots on Small Bear. Should I get 20 or 25k timpots?
Quote from: Ultrakd on November 10, 2011, 04:54:14 PM
Hey I cant find any 22k timpots on Small Bear. Should I get 20 or 25k timpots?
25
I ordered my bored and my parts are on the way :)
Hi, Building the TTT and wanted info on the LED. The LED on the board and the one which is wired to the 3pdt signifies the rate. Correct.? if so, how would the on/off LED be wired to the switch. I generally use a different wiring for the 3pdt. Also could I just wire the LED to the board directly and bypass the footswitch? Thanks
Yep, you can wire the rate LED straight to the board, then use standard 3pdt wiring for another LED.
Hey Taylor,
Sent you an email, and a PM about my order. Did you get them?
Thanks!
Kevin
Hi Kevin, Pm replied.
Hi, One more question regarding the pot orientation. The wave distort is self explanitory however the other pots are not indicated. I mounted the tempo, waveform and the multiply board mounted and underneath the PCB. From what I can gather that is wrong darn it. I may have to desolder (yuk) and reinstall. I am at a standstill. Please help. Thanks
There used to be a photograph showing the orientation, but it seems to have disappeared. The pots should go on the underside of the board, but pointing up so that they are not obscured by the board. I'll post a picture today.
But it also seems worth mentioning that a lot of my DIY pedals over the years have had backwards pots, and that never really bothered me personally.
Yeah, I screwed up, I may be ordering another board as I will most likely end up pulling up a pad etc. Shame as I was going great until now. I even decaled the enclosure to fit the wrong configuration. Se la vie. :'( :icon_sad:
Ok, check this post:
http://www.diystompboxes.com/smfforum/index.php?topic=84109.msg700055#msg700055
For the tremolo, it's the opposite of the two ways shown for the EB. So the pots go on the back of the board like the bottom photo, but pointing upward like in the top photo.
Removing pots from a double sided board without pulling the pads up is quite possible - I have done it many times without messing up the board. Just flow a lot of solder onto and into all the pads. Then heat one pad up so that it's fully molten all the way through and pull that end up, then do the center and it should pop up on its own. Then do the other end. Continue that way and get each leg out individually. Then use a solder sucker or braid to pull all the excess solder out of the pads before soldering it in the other way.
Thanks, I didn't think to pull one pad up at a time. I got them off anyway. I have regular pots (non-board mounted) and have already soldered the pots on. We'll see. I wish that I wasn't so impulsive sometimes
Chip and board came on Saturday. Once I get my bench a little more clear this is going to get my full attention. I'll post my results :icon_wink:
-Kevin
I got my pcb board today.. I wasnt able to find how to add a expression jack to the pedal though. Does anyone have any links as to how to do it?
get a switching jack, wire the 3 wires of the pot you want to control from the wire to the switched side (usually 1-2-3 goes to Sleeve-ring-tip respectively), and the corresponding 3 wires from the other side of the switching jack back to each correct pad hole on the PCB. This way when nothing is plugged in, the switching jack stays closed and the pot is engaged. When you plug in the expression pedal the switch contact is broken, so the pot is out of the circuit and the pot in your expression pedal replaces it.
Hi, I am living just outside Johannesburg, South Africa and have just come across this project via a link on the BYOC website. Do we have any other S. African's on this thread?
Although getting some of the rarer components down here can be difficult, I think I will probably go ahead and build the tap tempo tremolo. Most of my pedals are in 125B enclosures and I would like to fit this one in the same enclosure. I have three questions
1. The size of the circuit board?
2. The max current draw at 9V supply?
3. Has anyone managed to fit the TTT with all the pots, both footswitches, input and output jacks, dc power jack, and 9V battery in to a 125B?
Thanks in anticipation of your answers. :)
Have built my TTT and got rid of the little bit of ticking pretty easily but I also have a high frequency oscillation which is in time with the LFO so presumably the LFO is producing these oscillations so I tried the tips in this thread for sorting the ticking such increasing the 330pF to 1n and wiring the bypass to include the rate LED which helped a lot but I'm still left with a a low volume of super frequency oscillations, best way to describe it is a kin to the tinnitus ringing sound and it's equally as annoying too. The only difference in my circuit is that I used 10K trimpots and 220n on the input of the regulator which shouldn't have any affect here.
Anyone have any ideas or encountered this problem before?
Quote from: Barcode80 on November 21, 2011, 05:50:14 PM
get a switching jack, wire the 3 wires of the pot you want to control from the wire to the switched side (usually 1-2-3 goes to Sleeve-ring-tip respectively), and the corresponding 3 wires from the other side of the switching jack back to each correct pad hole on the PCB. This way when nothing is plugged in, the switching jack stays closed and the pot is engaged. When you plug in the expression pedal the switch contact is broken, so the pot is out of the circuit and the pot in your expression pedal replaces it.
So wire the pot to the switch (1-2-3 to Sleeve-ring-tip) then the switch to the correct holes on the PCB?
Quote from: Johnny B on November 22, 2011, 09:48:35 AM
Hi, I am living just outside Johannesburg, South Africa and have just come across this project via a link on the BYOC website. Do we have any other S. African's on this thread?
Although getting some of the rarer components down here can be difficult, I think I will probably go ahead and build the tap tempo tremolo. Most of my pedals are in 125B enclosures and I would like to fit this one in the same enclosure. I have three questions
1. The size of the circuit board?
2. The max current draw at 9V supply?
3. Has anyone managed to fit the TTT with all the pots, both footswitches, input and output jacks, dc power jack, and 9V battery in to a 125B?
Thanks in anticipation of your answers. :)
The board is about 2 inches by 3 inches. It will fit in a 125b, but it's not going to be easy to get everything in.
Quote from: moose23 on November 22, 2011, 12:58:40 PM
Have built my TTT and got rid of the little bit of ticking pretty easily but I also have a high frequency oscillation which is in time with the LFO so presumably the LFO is producing these oscillations so I tried the tips in this thread for sorting the ticking such increasing the 330pF to 1n and wiring the bypass to include the rate LED which helped a lot but I'm still left with a a low volume of super frequency oscillations, best way to describe it is a kin to the tinnitus ringing sound and it's equally as annoying too. The only difference in my circuit is that I used 10K trimpots and 220n on the input of the regulator which shouldn't have any affect here.
Anyone have any ideas or encountered this problem before?
I haven't heard of that issue. Are you using a nonstandard crystal? What type of power supply are you using?
Quote from: Ultrakd on November 22, 2011, 01:52:39 PM
Quote from: Barcode80 on November 21, 2011, 05:50:14 PM
get a switching jack, wire the 3 wires of the pot you want to control from the wire to the switched side (usually 1-2-3 goes to Sleeve-ring-tip respectively), and the corresponding 3 wires from the other side of the switching jack back to each correct pad hole on the PCB. This way when nothing is plugged in, the switching jack stays closed and the pot is engaged. When you plug in the expression pedal the switch contact is broken, so the pot is out of the circuit and the pot in your expression pedal replaces it.
So wire the pot to the switch (1-2-3 to Sleeve-ring-tip) then the switch to the correct holes on the PCB?
yes.
Is the expression pedal jacks a good mod to have? Whats your opinions?
Quote from: Taylor on November 22, 2011, 01:54:44 PM
Quote from: Johnny B on November 22, 2011, 09:48:35 AM
Hi, I am living just outside Johannesburg, South Africa and have just come across this project via a link on the BYOC website. Do we have any other S. African's on this thread?
Although getting some of the rarer components down here can be difficult, I think I will probably go ahead and build the tap tempo tremolo. Most of my pedals are in 125B enclosures and I would like to fit this one in the same enclosure. I have three questions
1. The size of the circuit board?
2. The max current draw at 9V supply?
3. Has anyone managed to fit the TTT with all the pots, both footswitches, input and output jacks, dc power jack, and 9V battery in to a 125B?
Thanks in anticipation of your answers. :)
The board is about 2 inches by 3 inches. It will fit in a 125b, but it's not going to be easy to get everything in.
Quote from: moose23 on November 22, 2011, 12:58:40 PM
Have built my TTT and got rid of the little bit of ticking pretty easily but I also have a high frequency oscillation which is in time with the LFO so presumably the LFO is producing these oscillations so I tried the tips in this thread for sorting the ticking such increasing the 330pF to 1n and wiring the bypass to include the rate LED which helped a lot but I'm still left with a a low volume of super frequency oscillations, best way to describe it is a kin to the tinnitus ringing sound and it's equally as annoying too. The only difference in my circuit is that I used 10K trimpots and 220n on the input of the regulator which shouldn't have any affect here.
Anyone have any ideas or encountered this problem before?
I haven't heard of that issue. Are you using a nonstandard crystal? What type of power supply are you using?
I'm using this Quartz Crystal QM002 http://www.banzaimusic.com/Quartz-Crystal-QM002.html
and a regular Boss PSA power supply.
Also opto is Silonex NSL32 and the regulator is a 78L05.
Im sure this is a stupid question but with the photocoupler does the long leads go into the holes where the + is or do the short leads?
Quote from: moose23 on November 23, 2011, 03:59:30 AMI'm using this Quartz Crystal QM002 http://www.banzaimusic.com/Quartz-Crystal-QM002.html
That's a 2MHz crystal you have there. You need a 20MHz (http://www.banzaimusic.com/Quartz-Crystal-QM020.html) crystal.
Quote from: Ultrakd on November 23, 2011, 08:18:35 AM
Im sure this is a stupid question but with the photocoupler does the long leads go into the holes where the + is or do the short leads?
http://www.silonex.com/datasheets/specs/images/pdf/103708.pdf
The dot indicates the cathode of the LED side of the optocoupler. :)
Mike
Quote from: .Mike on November 23, 2011, 12:34:09 PM
Quote from: moose23 on November 23, 2011, 03:59:30 AMI'm using this Quartz Crystal QM002 http://www.banzaimusic.com/Quartz-Crystal-QM002.html
That's a 2MHz crystal you have there. You need a 20MHz (http://www.banzaimusic.com/Quartz-Crystal-QM020.html) crystal.
Quote from: Ultrakd on November 23, 2011, 08:18:35 AM
Im sure this is a stupid question but with the photocoupler does the long leads go into the holes where the + is or do the short leads?
http://www.silonex.com/datasheets/specs/images/pdf/103708.pdf
The dot indicates the cathode of the LED side of the optocoupler. :)
Mike
Ah totally messed up on that myself so. Thanks for the quick help. I'll order the right one now, hopefully it'll work perfectly.
Quote from: .Mike on November 23, 2011, 12:34:09 PM
Quote from: Ultrakd on November 23, 2011, 08:18:35 AM
Im sure this is a stupid question but with the photocoupler does the long leads go into the holes where the + is or do the short leads?
http://www.silonex.com/datasheets/specs/images/pdf/103708.pdf
The dot indicates the cathode of the LED side of the optocoupler. :)
Mike
Ok so that would mean that the long lead on the side with the dot is the anode of the LED and goes into the + correct? Sorry for the noob question :P
Quote from: Ultrakd on November 23, 2011, 01:34:59 PM
Quote from: .Mike on November 23, 2011, 12:34:09 PM
Quote from: Ultrakd on November 23, 2011, 08:18:35 AM
Im sure this is a stupid question but with the photocoupler does the long leads go into the holes where the + is or do the short leads?
http://www.silonex.com/datasheets/specs/images/pdf/103708.pdf
The dot indicates the cathode of the LED side of the optocoupler. :)
Mike
Ok so that would mean that the long lead on the side with the dot is the anode of the LED and goes into the + correct? Sorry for the noob question :P
Check the very first post in this thread - it's explained there.
Finished up the TTT. Wow great and extremly versitile pedal. I was able to trim out the tic fras well which was only marginal anyway. Good stuff. ;D
(http://images3a.snapfish.com/232323232%7Ffp73449%3Enu%3D8%3A%3A8%3E635%3E258%3EWSNRCG%3D3477728243349nu0mrj)
[(http://images5a.snapfish.com/232323232%7Ffp63638%3Enu%3D8%3A%3A8%3E635%3E258%3EWSNRCG%3D347772823%3B349nu0mrj)
Nice work ;)
Mine is also finished this weekend. The only problem I encounter is the use of the Tap Tempo stompbutton.
It need debouncing I guess... When pushing the button, it reacts like i pressed it 5 times...
Anyone an idea how to debounce this button? Or must the code be rewritten?
At first I had that problem, but pretty quickly I got the hang of how it needs to be tapped - it's just a feel thing really. There is debouncing in the code but it wouldn't be too hard to add more if you needed it.
Owkidow! Indeed, it's pretty hard to get the feeling for tapping this button... I use the Carling 1PST momentary footswitch, a very good switch, so it should be ok I guess.
Let's just play some hours, days, ... to get the feeling in my left toe to operate this button :icon_twisted:
Ok having some problems :/.....1st when the pedal is in bypass its fine. But when I turn it on I dont get any input sound...just this woooping sound . What did I do wrong? 2nd can I put 2 leds on the bored where they always stay on blinking to the tempo?
The problem will be in your audio path, so the tl072 and the parts surrounding it. Trace through the circuit from input to output with an audio probe (read "what to do when it doesn't work" sticky thread at the top of this forum) and find where the audio stops.
Do you have your optocoupler oriented correctly? See the first post in this thread on page 1 for details.
Did you tweak the trimpots around?
Quote from: Taylor on December 04, 2011, 02:23:36 PM
The problem will be in your audio path, so the tl072 and the parts surrounding it. Trace through the circuit from input to output with an audio probe (read "what to do when it doesn't work" sticky thread at the top of this forum) and find where the audio stops.
Do you have your optocoupler oriented correctly? See the first post in this thread on page 1 for details.
Did you tweak the trimpots around?
Ok I took the switch out of the equation and just wired it so the effect is on and it works but one of the main problems Im having is with the volume knob. I have the A25k pot on there but it doesnt change sound until halfway. Before that there is no sound, like its turned off. And when it is all the way up it isnt that loud. I had my amp completely turned all the way up and it was still low volume. What could be causing this? Yes I tweaked the trimpots and Im 99% sure the optocoupler is oriented correctly.
Sounds like there's probably an open circuit somewhere in the audio path (bad solder joint?) and the sound is only making it through because of bleed. Try reflowing your solder joints.
A few weeks ago, I decided to built the tap tempo tremolo after making an EA tremolo. I ordered all the parts and even managed to find a supplier for the NSL-32 in RS components here in South Africa. They were on 14 days delivery from the local supplier sourced from RS in the UK.
Today I received a call from the local RS people to say that they now cannot source the NSL-32 even though it states availability on their website and they accepted my order a week ago. So now I'm in trouble. I cannot find any other source in South Africa and most overseas suppliers require minimum order quantities and high shipping costs.
Is there any kind soul who would be prepared to put two in an envelope for me and post them to South Africa? I'll happily pay all the costs.
Thanks in anticipation.
Hi again from South Africa. I am battling to find NSL-32 optocoupler down here in SA but I might be able to find something in the Perkin Elmer VTL5CX range. I know that at one stage 'thehoj' was deliberating which one to use. Has anyone used a Vectrol. Which one did you use and did it work OK?
I haven't used vactrols in this circuit, but they should work as long as they have a similar on/off resistance and speed. There's a big perkin-elmer datasheet with the info for all the vactrol series to compare.
Got my ttt built, lfo works and no ticking so far. Biggest problem right now is the signal is very clipped/distorted. Any ideas were to go with that?
-kevin
You probably need to turn down the gain (trimpot above the tl072). This may mean readjusting the opto trimmer to get unity gain.
I've played with all the trim pots and the signal when it comes through is always clipped
Even at minimum gain? If so, I guess the first opamp stage is clipping - possibly the biasing resistor has a bad solder joint? What kind of signal are you putting into it?
Which resistor woud that be? I was testing with an old teisco with a single coil in the neck.
I don't see any biasing resistors in the schematic, just pull-downs. It looks like Vref is connected straight to the opamp on the schematic. Either way...
Check the two side-by-side 100k resistors that create Vref. Each should measure about half of the power supply on the ends closest to the middle of the board. If you get half of the supply voltage there, check pins 3 and 5 of the opamp. Both should also be at about half of the supply voltage.
You can also check the two 220k resistors, which set the gain of the first stage. Double check to make sure they are they right value. If, for example, you accidentally used a 22k and a 220k, you could end up with a gain of 10 instead of a gain of 1. That could overload the second stage, which is set by the LDR side of the Vactrol, and the 10k trimpot that is situated (I think) between the Vactrol and the 330p capacitor.
:)
Mike
I guess I should go look at the schem rather than just go on memory! :D It's been long enough since I looked at it that I was thinking that they were non-inverting amplifiers.
Good suggestions, Mike.
Thanks guys, hoping to get a look at this tonight, and let you all know my progress
-Kevin
Ok I was just able to get back and reflow my solder joints and to rewire the board. I was wondering though for the LED that blinks constantly, can I put 2 there or will the 2 trimmers not be able to take out the ticking?
Hey All,
Did some voltage testing last night, and didn't find anything immediatley alarming. Voltages at the recommended test places were about half of the incoming voltage from my power supply, so on a whim and a hunch I decided to try sticking in a diffrerent TL072. Boom! We got tremolo! I'm still working on tuning the circuit, now that I have the a working audio section I've got the dreaded tick that some others have encountered. I initally had two NSL32s to try, but the first one's leads broke off from me trying to figure out which way it went in. I also may try the cap change that was mentioned earlier in this thread.
Does this Tremolo get very deep/choppy? I've tried it a couple times with everything cranked (depth and trim pots) so it was clicking like crazy, but still didn't seem to get real deep. I need to spend some more time with it as I don't have anything labeled, so I'm not sure what waveform I was on etc (I know squarewave is the best for the super choppy stuff). As always, I will post my progress.
Thanks!
-Kevin
Quote from: Jamforthelamb on December 29, 2011, 09:53:55 AMI also may try the cap change that was mentioned earlier in this thread.
If I remember right, isn't that just increasing one of the caps? You should be able to see if that will work for you by holding/jamming a cap in parallel with the cap that is currently in place.
QuoteDoes this Tremolo get very deep/choppy? I've tried it a couple times with everything cranked (depth and trim pots) so it was clicking like crazy, but still didn't seem to get real deep. I need to spend some more time with it as I don't have anything labeled, so I'm not sure what waveform I was on etc (I know squarewave is the best for the super choppy stuff). As always, I will post my progress.
Yep, definitely gets choppy. You have to use a combo of square wave and high speed, and then adjust the wave distort knob. Stick wave distort in the middle, set for square, and crank the speed up. Adjust the wave distort to get the choppiness you want. :)
Mike
Quote
If I remember right, isn't that just increasing one of the caps? You should be able to see if that will work for you by holding/jamming a cap in parallel with the cap that is currently in place.
That was my exact plan :). Looks like it was recommended to use a 1nf in place/on top of the 330pf in the audio section. Going to try that tonight hopefully.
QuoteYep, definitely gets choppy. You have to use a combo of square wave and high speed, and then adjust the wave distort knob. Stick wave distort in the middle, set for square, and crank the speed up. Adjust the wave distort to get the choppiness you want. :)
That was my next question. When using the wave distort knob how does it effect the sound as you turn it left to right. Is it less distorted/normal all the way to the left adding more as you turn right, or something different?
Thanks!
-Kevin
Quote from: Jamforthelamb on December 29, 2011, 05:34:05 PMThat was my next question. When using the wave distort knob how does it effect the sound as you turn it left to right. Is it less distorted/normal all the way to the left adding more as you turn right, or something different?
It's a misnomer. It is the waveshape that distorts, or more accurately
skews based on the wave distort setting. There is no audible distortion.
Take a look at these images, and see if it helps understand what it does:
http://www.electricdruid.com/images/lfo/PDDiagramV9C.gif
(http://img199.imageshack.us/img199/1135/wavedistortnoise.th.jpg) (http://img199.imageshack.us/my.php?image=wavedistortnoise.jpg)
And finally, here is an audio sample I made to demonstrate the wave distort feature using the Taplfo's predecessor, the VCLFO.
Wave Distort demo, Square wave, Full counter-clockwise to full clockwise: Link (http://mikesblog.americasdebate.com/uploads/pictrem/WaveDistort.mp3)
:)
Mike
Hi Mike,
Cool, thanks for the info. I got that it doesn't actually "distort" the sound, but rather the way the wave is shaped. I was questioning more on the way the knob functioned. So, it looks like the wave is not effect in the center position, and then will change depending on which way you turn it. That about right?
Thanks!
-Kevin
Got to spend some more time with my TTT. With the wave distort knob centered had a much easier time dialing almost all the click out (except on extreme settings). It's so tight to push a cap over the 330pf cap that I may have to try and just trim it out and solder in a different cap, but the clicking last night in my smaller amp was nearly gone so I may not have to. It will really depend on how it plays with my main amp tonight. All I have left to do is make a decal for it, and wire the LED to the bypass switch using Taylor's updated layout. It's too embrassing to photograph right now cause the enclosure is naked and tattooed with sharpie lol.
Thanks again for everyone's help!
-Kevin
just wondering-is there a way to build a 2 knob (speed and depth) type tremelo with a tap tempo input jack? does anyone have a hero layout for it?
Ok I think I messed up my board. The first time I wired everything up I used 22awg wire which I had to shove in some places. I went and got some 26awg now and when I was pulling some of the wires out I pulled out some of the pads. Did I mess up my board, should I get a new one? Another one of my problems is I haven't been able to get the ticking to go away from the light.
Regarding your board, we can't really know if you messed it up unless we know what it's doing. If it's working, then it's good.
There's a lot of info on fixing the tick in this thread, if you read over it.
one problem is the multiplier footswitch isnt working. One of its pads good pulled out . Also the volume/gain isnt really working. Im using a pot instead of a trimmer, which hole goes to which lug?
Looking at the silkscreen side of the board, with the tempo pot at the top...
The upper mult switch pad connects to the little via to the right of the 78L05. The lower pad connects to ground.
Gain knob: The upper pad should go to one outer lug of your pot, and the lowest pad should go to the wiper of your pot. Don't connect anything to the middle trimpot pad.
Quote from: Taylor on January 01, 2012, 06:27:37 PM
Looking at the silkscreen side of the board, with the tempo pot at the top...
The upper mult switch pad connects to the little via to the right of the 78L05. The lower pad connects to ground.
Gain knob: The upper pad should go to one outer lug of your pot, and the lowest pad should go to the wiper of your pot. Don't connect anything to the middle trimpot pad.
Ok so the upper multi switch lug goes to that little hole to the right of the 78L05. What are the other 3 little holes on the board for?
They are vias. They connect the top and bottom copper layers. You don't need to do anything with them. In the case of the multiplier switch we're just using that via because it's an available place to which you can solder, but in normal use you can and should ignore vias.
Ok now nothing is working...I think I might need to get a new board and be more careful with the next one. I think I just messed up to many of the pads. How much is just a board?
I'm hoping someone can help me.
I am wanting to do the rotary switches for the Waveform and the Multiplier pots. I got the Waveform working properly. I did have to switch the +5v and the ground wires around because it was working backwards. That fixed it.
I'm having problems with the Multiplier rotary. Again, I had to switch the +5v and ground wires to get it to not work backwards. My drawing illustrates this but my board illustration below doesn't.
The issue I'm having is the steps start out slow and progressively increase until I reach position 6. It goes back to the slowest tempo again.
I had a 5k resistor on each end (R1 and R7) and both positions 5 and 6 went back to the slowest setting.
I replaced one 5k with a 10k in R7 and that fixed position 5 but 6 still went back to the slowest.
I then put 10k in all of them and that didn't change anything. Positions 1-5 are ok but 6 goes back to the slowest.
I'm using the 6 position rotary from Smallbear. I triple and quadruple checked my board. I read to "not use the two top positions" and I assumed that meant the top 5k and the first 10k. I also removed the 3k6 resistor going to the Multiplier pot.
Here are the voltages I'm getting in each position which seem like they would be right. There is also the board I'm using. Remember I had to reverse the +5v and ground to get it to not work backwards which the board doesn't reflect.
(http://i69.photobucket.com/albums/i44/bside2234/multiswitch2troubleshoot.jpg)
Quote from: bside2234 on January 05, 2012, 04:57:57 PMI read to "not use the two top positions" and I assumed that meant the top 5k and the first 10k.
I wonder if there is a bit of confusion with this. Like the datasheet says, the top two options are not used, but the resistance still must be there for the voltage divider to work right.
Add up your string of resistors. Does it equal 80K?
:)
Mike
Oh!!!!! Seven 10k resistors = 70k. I see now. I still need to use 9 resistors but I will be "tapping" into the 6 junction points for the 6 position switch. Correct? So if I tack on an extra 10k and 5k in series on the end, hook the wire up to that and change the resistor on the other end to 5k, I should be in business. I'll try it in the morning. I did get a little confused with that part. I took it as they weren't needed at all. Obviously!
Edit: Technically, I should be able to just put a 15k resistor on the "unused" end which would be a little cleaner. Right? Man, I'm not going to be able to sleep tonight. I've been mulling over this for a few days now.
Yes, I believe that is how it works.
In theory, you can use 5K (tap1) 10K (tap2) 10k (tap3) 10k (tap4) 10k (tap5) 10k (tap6) 25k. :)
Mike
Sweet! That would even be nicer as I can use the existing pads. I'll give it a try. Thanks.
Edit: Tried the 25k and it worked like a charm. Thank you!
Any ideas for getting rid of a pop which switching it on?
Mine doesn't pop.
Does anyone know where to source nice graphics of the waveshapes of the TTT to use on the pedal decal?
Quote from: Johnny B on January 13, 2012, 09:48:11 AM
Does anyone know where to source nice graphics of the waveshapes of the TTT to use on the pedal decal?
Since I plan on etching them into mine when I (finally) build it, I put together a 1200dpi vector PDF to share.
It should preserve the quality no matter how you scale it if you use the Acrobat print scaling.
Taplfo Waveshapes - 1200dpi.pdf (http://www.americasdebate.org/Taplfo%20Waveshapes-1200dpi.pdf)
I also have the PSD if anyone wants it. :)
Mike
Quote from: .Mike on January 13, 2012, 08:37:53 PM
Quote from: Johnny B on January 13, 2012, 09:48:11 AM
Does anyone know where to source nice graphics of the waveshapes of the TTT to use on the pedal decal?
Since I plan on etching them into mine when I (finally) build it, I put together a 1200dpi vector PDF to share.
It should preserve the quality no matter how you scale it if you use the Acrobat print scaling.
Taplfo Waveshapes - 1200dpi.pdf (http://www.americasdebate.org/Taplfo%20Waveshapes-1200dpi.pdf)
I also have the PSD if anyone wants it. :)
Mike
Thanks, Mike. The waveforms cut, paste and resize perfectly. Has anyone worked out the angular position of the pot for each of the 8 waveforms? I am using a 16mm Alpha pot with a 300 degree rotational angle.
I think I may have answered my own question on the waveform pot angular positions. I have based the calcs on a pot with 300 degree rotation. I used the resistor chain shown on page 8 of the Tapflo datasheet with 7 10k resistors and a 5k on each end. The angles are calculated from the vertical ( 6 o'clock).
Position Degrees
1 48.75
2 86.25
3 123.75
4 161.25
5 198.75
6 236.25
7 273.75
8 311.25
Can anyone confirm?
Personally, I think you are making it a lot more work than it needs to be plus if the tolerance of pots (the actual value not what is written on it) comes into play, you will be off.
I would build the pedal, tape a piece of paper to the pedal around the pot, mark all the positions on the paper and either scan it and use that to make the graphic or just eyeball it from there. I think you may find that the switching points aren't exactly even. At least on the first one I built. I just marked each position directly on the enclosure and they are not very even where they switch over. It may just be mine though.
Quote from: moose23 on November 23, 2011, 01:10:44 PM
Quote from: .Mike on November 23, 2011, 12:34:09 PM
Quote from: moose23 on November 23, 2011, 03:59:30 AMI'm using this Quartz Crystal QM002 http://www.banzaimusic.com/Quartz-Crystal-QM002.html
That's a 2MHz crystal you have there. You need a 20MHz (http://www.banzaimusic.com/Quartz-Crystal-QM020.html) crystal.
Quote from: Ultrakd on November 23, 2011, 08:18:35 AM
Im sure this is a stupid question but with the photocoupler does the long leads go into the holes where the + is or do the short leads?
http://www.silonex.com/datasheets/specs/images/pdf/103708.pdf
The dot indicates the cathode of the LED side of the optocoupler. :)
Mike
Ah totally messed up on that myself so. Thanks for the quick help. I'll order the right one now, hopefully it'll work perfectly.
and it dig work perfectly, cheers for the help. Lovely sounding pedal and lovely boards to work with.
CRAP where can I purchase an NSL-32 ???
Quote from: Gaetano Capuano on January 20, 2012, 11:42:28 PM
CRAP where can I purchase an NSL-32 ???
http://www.smallbearelec.com/Detail.bok?no=356 (http://www.smallbearelec.com/Detail.bok?no=356) Small Bear Electronics is your best fiend ;)
There is my build
(https://lh5.googleusercontent.com/-DXz7I6fnJCE/TxCEKcu3G-I/AAAAAAAAAPM/yRHmLpEvsLQ/s640/P1130029.JPG)
For waveform and multiplier i using rotary switches instead of pots. That makes these functions a bit more understandabe. If someone interested - i found perfect rotary switches for that
http://eu.mouser.com/ProductDetail/ALPS/SRBV160803/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRYaNeyNyivdg%3d (http://eu.mouser.com/ProductDetail/ALPS/SRBV160803/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRYaNeyNyivdg%3d) 6 position for multiplier
http://eu.mouser.com/ProductDetail/ALPS/SRBV181004/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRbZTSllc6Pt4%3d (http://eu.mouser.com/ProductDetail/ALPS/SRBV181004/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRbZTSllc6Pt4%3d) 8 position for waveform
All you need to do is build additional PCB
There is PCB's (open with Sprint Layot)
with trough hole resistors (https://docs.google.com/leaf?id=0BxW0oyyuIeI7MjkwZTQ1YWEtMDVlNC00NmE2LWIxODgtYTA4NTczOWFlZmQ5&hl=en_US)
NOT VERIFIED because i build second one version with SMD (8060 size) resistors
with SMD (8060)resistors (https://docs.google.com/leaf?id=0BxW0oyyuIeI7NTRjZWY3YzYtNTVjOC00OWIxLTk1YTItM2Y3MTQ0NDA4NGI0&hl=en_US)
VERIFIEDall PCB's is
ready to trasfer
Could you post an image file of that layout? Or a schematic version of it? I don't have the program to open this layout.
So it seems a few have said get a few optocouplers cause some are noisier than others, yet all the builds they look like they are not socketed. Would you recomend socketing them?
Also seems it may be awkward using regular pots for the wave form and subdivision pots, any thoughts on this?
Also a guy who built one recommended surface mount pots to help prevent noise issues :icon_mrgreen:
I am gonna be building this one over the next few days or so, pics coming soon.
Quote from: Valoosj on January 26, 2012, 05:15:16 PM
Could you post an image file of that layout? Or a schematic version of it? I don't have the program to open this layout.
There is no reason post image files, because when you will print it, you can't be sure that it will be in correct size
Just download and install Sprint Layout viewer. It's for free!
http://www.abacom-online.de/uk/html/sprint-layout.html (http://www.abacom-online.de/uk/html/sprint-layout.html)
Scroll down to the end. There is a viewer download link ;)
With this viewer you can open .lay files and print it in correct size.
Quote from: Gaetano Capuano on January 26, 2012, 06:19:17 PM
So it seems a few have said get a few optocouplers cause some are noisier than others, yet all the builds they look like they are not socketed. Would you recomend socketing them?
Also seems it may be awkward using regular pots for the wave form and subdivision pots, any thoughts on this?
Also a guy who built one recommended surface mount pots to help prevent noise issues :icon_mrgreen:
I am gonna be building this one over the next few days or so, pics coming soon.
Of course you can use sockets for optocouplers, but IMO - that's a waste of money. They have only 4 pins, so you can easy change it if needed :) I was try both of recommended optocouplers - VTL5C3 and NSL-32. Stayed with NSL-32.
Yes, i think rotary switches is better than pots. If you using pots, you can't be really sure where is the point when waveform or multiplier stages changes. With rotary switches this is more comfortably.
thanks dude 8)
Hi everyone,
I built the tap trem for a friend and it worked perfect. I brought it over to his place to try it, i forgot to bring my 9v adaptor i was using so he hooked an adaptor to it. I had no idea, but he hooked up an 18v adaptor and now the unit ticks like crazy, the waveform selections are all off and when its bypasses it still clicks and make weird feedback noises. Do any of you gents out there know what is bad in the unit now? i think it could be the trem ic, but I'm not sure. I'm going to get new chips anyway, but i wanted to hear others opinions in case there is something else wrong that i didn't know about.
Thanks a bunch,
Lucas
bummer :'(
Try the 7805 and see if you get 5V out of it. I had a similar issue due to a wrong pinout of the thing. Mistook it for a 78L05.
Wow, I put the one diode in backwards, plugged it in, fired it up, and the resistor next to it became a burning ember :'(
Crp, is my whole project shot???????????
Whoa now. Hold up. The easiest way to ensure your project is shot it to start replacing random components without knowing why.
Your resistor burning is a symptom of something pulling too much current. What's pulling too much current? Your diode. When you turned it around, you setup a situation where your circuit is a dead short across a 10-ohm resistor.
Replace the diode and the resistor.
Remove the TAPLFO IC.
Power the effect.
Measure and share the following voltages: battery, all pins of your voltage regulator, all pins on your TAPLFO socket.
That is where I would start. :)
Mike
Oh I was jsut about to give up ::)
Maybe I should re group and replace these pieces?
Ok, I replaced the resistor and the diode, put a new diode in the correct way. Plugged it in and it seems to be working. Its not mounted in an enclosure, but I alligator cliped the hot tothe hot of a dc adpter, and the ground to the ground, plugged it in, switched it on, and the LED flashes with tempo, when engaged I need to be touching the ground on the jack to get the signal to pass through, I assume because its not in an enclosure. The flashes change with the waveforms, the effected signal is lower than bypass signal, I did not have time to bias and all that, so I hope I am on the right track.
I recommend connecting all ground with wires rather than expecting the enclosure to do the grounding for you. JAcks can become loose, etc.
Quote from: Taylor on January 31, 2012, 04:08:06 PM
I recommend connecting all ground with wires rather than expecting the enclosure to do the grounding for you. JAcks can become loose, etc.
Yeah I do.
I was being hopeful, but its not that. When engaged there is no signal, when I mess around with the 3PDT and squeeze the lugs I can get a signal.......... The LED works, blinks to tempo and wave form.
Thoughts? All my wiring looks good.................
Squeeze the lugs of what? If it's the 3pdt then it might be a bad switch.
Make sure when getting it setup to put the wave distort knob in the center - at some extremes it will barely cut on. At that point you may just need to tweak the trimpots. if that doesn't get anything going then the usual debug technique with an audio probe may be in order. The audio section is pretty small, so if you LED is flashing you're pretty close.
yeah the lugs of the 3pdt, which makes me think it might be something in the wiring.
OK guys, I got my audio probe out. Actually just built one. I cant tell where the audio path of this circuit is though. I do have nice, pulsing coming out of the led side of my optocoupler though :icon_razz:
Help
Wiring should be done like that. Check signal in these testpoints, and then tell us where you lost it.
https://docs.google.com/leaf?id=0BxW0oyyuIeI7NWE1NWYzMTktY2I0Ni00MjViLTljNTItOGYwYTI1Yjg0YzY4&hl=en_US
I just realized I only have 4 10KB pots, but my box is drilled to implement all five (including wave dist, no ext gain pot). I have lots of other linear pots (5k, 20K, etc) and I could do the parallel resistor thing, but that will make my pot act as a Log pot.
Can a 20KB or 50KB pot be subbed in anywhere? Otherwise, will a 10KB (makeshift) be usable for any of the controls?
The waveform pot needs to be 10k because of the resistor in series with it, although you could use another value if you recalculated the resistor value. The other pots can be any value.
Quote from: Beo on February 03, 2012, 02:23:49 PM
I just realized I only have 4 10KB pots, but my box is drilled to implement all five (including wave dist, no ext gain pot). I have lots of other linear pots (5k, 20K, etc) and I could do the parallel resistor thing, but that will make my pot act as a Log pot.
Can a 20KB or 50KB pot be subbed in anywhere? Otherwise, will a 10KB (makeshift) be usable for any of the controls?
It will be usable for all the controls, you just won't have the available range you have with the correct pots. So if you were supposed to use, say, a 100K pot, you could use a 10k but your range of available settings would only be what was supposed to be the first 1/10 of the dial.
Quote from: Barcode80 on February 03, 2012, 04:49:01 PM
It will be usable for all the controls, you just won't have the available range you have with the correct pots. So if you were supposed to use, say, a 100K pot, you could use a 10k but your range of available settings would only be what was supposed to be the first 1/10 of the dial.
That would be true if the pots were wired as rheostats (variable resistors - 2 terminals) but in this case they are voltage dividers, so as slacker says, you can use other values for all but the
multiplier pot (not the waveform pot) with no penalty at all. 50k is a fine sub - bigger values could theoretically become problematic as I don't remember how much current the pins expect.
Quote from: Taylor on February 03, 2012, 04:55:02 PM
That would be true if the pots were wired as rheostats (variable resistors - 2 terminals) but in this case they are voltage dividers, so as slacker says, you can use other values for all but the multiplier pot (not the waveform pot) with no penalty at all. 50k is a fine sub - bigger values could theoretically become problematic as I don't remember how much current the pins expect.
Crisis averted, I found some salvage 10kB pots from an old mixer I had. You're right that it doesn't matter. Looking at the schematic, most of the pots are straight voltage dividers varying 0-5v. Current feeding the chip would be reduced with a bigger pot, but probably wouldn't be an issue. Since it was spec'd for linear pots, I really didn't want to use a log pot if it would affect a useful control response.
Hi,
I want to build Wave form and Multiplier control with rotary switch.
Can anybody help me to mark voltage or resistance values for control steps:
Tnx
(https://lh3.googleusercontent.com/-b4fE084_Pic/T0N9XSjuERI/AAAAAAAABjs/kxHhS7CAmGk/s800/LFO_WAVE.jpg)
1 = xV, xR
2 = xV, xR
3 = xV, xR
4 = xV, xR
5 = xV, xR
6 = xV, xR
7 = xV, xR
8 = xV, xR
(https://lh3.googleusercontent.com/--VO0e0N9OLw/T0N9YYSOnvI/AAAAAAAABj0/q5m96pcXOlQ/s800/Multiplier.jpg)
A = xV, xR
B = xV, xR
C = xV, xR
D = xV, xR
E = xV, xR
F = xV, xR
Tnx
Look at page 8 of this pdf:
http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf)
This is what you need to know.
Hey guys, I'm new to the forum and this is my first somewhat successful build. I completed my Trem a couple of days ago and all functions work, with the exception of an unusual amount of humming, buzzing, and ticking. I've tried every trim pot combination possible, rewired the entire pedal with different combinations of routing methods, and reflowed most of the connections to ensure i wasn't getting cold joints. But the buzzing won't go away.... Anybody else had this problem??? The trem works, but the depth is really weak. The max value sounds like something I would expect around 40-50%. Any thoughts would be greatly appreciated!!!
Check the wiper of your depth pot to make sure it sweep fully from 0v to 5v.
If it does, then the low depth will be because of how you have the trimpots set. You probably have the opto trimmed down too low and the gain up high to compensate - this limits the quietest it will get in the off position.
The buzzing is less obvious. What sort of power supply do you have? Are you powering anything else with it at the same time? Pickups? Are all your ground points correctly connecting to ground (in and out jacks, the board, the box itself)?
I don't have a meter at home right now so I can't check that just yet.. Could I be having ground issues because I'm using plastic neutrik jacks? I've tried a one spot, a voodoo lab pp2+, a battery and 2 different guitars. 1973 Les Paul deluxe and a custom shop tele. Same story all around..
Also, where is the best ground to tie the switch to (bottom left pin) ??
Yes, if you have plastic jacks and no other way of connecting ground to your enclosure, then the box will not be doing its job of shielding. If you want to keep the plastic jacks you can scratch up the back of a pot and solder there to connect the box to ground. I recommend star grounding all grounds to the input jack sleeve.
Swapped out the plastic jacks for metal ones and that did the trick, other than a good bit of ticking, all features worked perfectly.. No combination of trim pots would make it go away..
30 minutes after this happened, I finished up another build and wanted to test them side by side. When I turn it on, all it does is buzzes and squeals really loud and won't pass any signal. So I've gone from perfect function to absolutely no function and I'm very confused. Could I be dealing with a bad opto??
Buzzing... doesn't play well with others... a shot in the dark, but is there any chance you accidentally confused signal and ground at the jacks?
I considered it, but it worked solid for like 30 minutes (with ticking) and now it won't pass signal at all. And it's making some terrible sounds
If you go back to just having the trem, does it act like it did before, or the same as when you have the two together?
It's all the same, tried different power supplies, guitars, and 2 different amps. No signal, just craziness. I'm really lost at this point..
hey everyone,
just have one question about the tap. i pretty much have it all good. i think i removed all ticking when its on, but when i have it bypassed you can hear the ticking. i have the circuit board output grounded when bypassed. should i do the same to the input? even if i have the lfo trim pot all the way down and the gain all the way down it still ticks. and the speed of the ticks are controlled by the tempo and multiplier pots. i didn't use the ultra bright blue led would that have something to do with it?
Anyway sorry to be a bother I'm just wondering why its making so much noise bypassed.
Thanks for your time,
Lucas
I posted an alternate bypass diagram that will completely kill the LFO in bypass. I believe it should be somewhere around page 7 of this thread.
Thanks for the help Taylor.
Lucas
Last question, if I got the pedal back up and running but have a pretty significant tick regardless of trim pot settings, am I dealing with a bad opto?
Also, I'm still not getting the depth I was expecting but I don't have anything to compare it to. If I'm getting less than 5 volts on the pot could that be why?
Thanks again for your help!
Quote from: Helloimjohn1234 on February 24, 2012, 01:54:38 PMLast question, if I got the pedal back up and running but have a pretty significant tick regardless of trim pot settings, am I dealing with a bad opto?
Not enough information provided to make that determination. The best we could do with what we know is an educated guess.
Passing on what you did to get it running might help us to help you in the diagnosis process. Photos and/or a debug report (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0) would likely help us to help you in the diagnosis process. :)
And yeah, if there is less than 5v on the 5v side of any of the pots, you won't be able to get the full range of that pot. If your 5v regulator isn't putting out 5v, you won't get the full range of any of the pots, and it would likely cause issues with the PIC (can't put out 5v pulses if you don't have 5v to start), and maybe the LEDs, which would impact gain.
Mike
Basically, I didn't have the jacks properly grounded to the enclosure which was causing some crazy sounds. It worked fine but was really noisy. I did a few tweaks and it wouldn't work at all, a ground wire had broken loose and I didn't see it.. Now I've got it up and running and can't get rid of the tick
I finished my tap tempo build the weekend before last and am still discovering all the things I can do with it. I had no problem with the build other than that I had a dud NSL-32 which I had to replace. I used a 1590BB and with 6 pots, 3 switches and an external tap input. It fitted perfectly. Here are a few pictures of the pedal
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0059Small.jpg)
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0060Small.jpg)
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0064Small.jpg)
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0065Small.jpg)
Did you have a ticking problem before you replaced your opto?
Quote from: Helloimjohn1234 on March 08, 2012, 01:16:12 PM
Did you have a ticking problem before you replaced your opto?
I built the circuit with C9 at 1nF rather than 330pF and had absolutely no problem with ticking.
Very nice pedal Johnny, inside and out. :)
Hi all,
Sorry that my next post is not about succeses :).
I finished today tremolo.
In the begining everything was ok (testing out of enclosure). No ticking.
But after some time somefing goes wrong and now tremolo have very loud ticking when waveform is ramp up ,ramp up or square position.
Even if trimpots R13 and R14 is max value (22k), ticking is very loud.
In another positions no ticking but is very very quite "sirene alarm type" whisteling (mayby becose the PCB is not in enclosure).
With 3 difrent type power supply (Boss PSA-120, Harley Benton PowerPlant and one another) is the same symptom.
Capacitor C9 is 1nF. Optocoupler is NSL-32
When i touch TAPLFO pin 3 with a tester or if i replase C2 with biger cap then 22pF, the ticking disapere but waveform sound to (just clean sound).
I replaced C1 and C2 (22pF) caps with a newer same value. But this useless.
I will try next things:
1. Replace optocoupler
2. Replace crystal
3. Is the possible that TAPLFO is some way was damaged?
Any another recomendation.
Tnx.
Quote from: .Mike on March 09, 2012, 01:16:57 AM
Very nice pedal Johnny, inside and out. :)
Thanks, Mike, for the compliment. You probably can't make it out on the photos, but on the front edge of the pedal is a South African flag and the words "In Suid Afrika vervaardig met bloudraad en tang", which is a 'tongue-in-cheek' Afrikaans quote for Made in South Africa with blue wire and pliers". Unless you know something of South African cultural history this may seen strange. The Afrikaner population of South Africa were mainly farmers, or "boers". Due to a lack of technological resources, people here had to use their ingenuity and "make a plan" if anything needed to be fixed or made. ( A bit like McGyver!). "Boer sal n plan maak" (the farmer will make a plan) is a commonly quoted SA phase when in a tricky situation. So the legend goes that no matter what the problem, as long as you had a piece of Blue (read fence) wire and a pair of pliers, you could fix anything. Hence the quote. ;)
Hi everyone, I've just finished the build of my Tap Trem.
I wanted to post some pictures for those who are interested about wiring a rotary switch for waveform select. I've simply soldered resistors between the legs of the switch and I've connected the switch to the board like a classic pot with 3 wires. (Sorry for my poor English, I hope I'm clear enough)
(http://gib.giz.free.fr/TTT1s.jpg)
(http://gib.giz.free.fr/TTT2s.jpg)
(http://gib.giz.free.fr/TTT3s.jpg)
Hey there I was wondering if any of you know whether or not these smallbear trimpots would fit. SKU number is 1015AB. I'm probably gonna order from small bear hopefully if I can get all of the components there. Unless there are other recommendations... I'm really sorry if this question has already been asked, but I am at work and am in a rush so I haven't been able to read the whole thread yet. Thanks again for any help/advice
So I just built the tap tempo trem successfully. I used the 330pf cap and have zero ticking. I need more depth on my depth knob though. I need some extreme chop going on sometimes. any suggestions?
Thanks.
Hmm.
The depth of the effect is determined by the 10k that is in parallel with the 330p, the second half of the opamp, and, the LDR side of the NSL-32. The NSL-32, unfortunately, does not have very tight specs.
If you give it 20mA of current, it'll hit its minimum of 500-Ohms or less. Give it 16mA and it'll hit about two-thirds of the minimum in 3.5 milliseconds. That's pretty fast. Going the other way is a different story. The maximum off resistance is at least 500k. If you feed it 16mA, and then remove the current, it will take up to a half a second to reach 100k. That's pretty slow.
Of course, we're going nowhere near 20mA of current, I don't think, at least not without ticking. The slowness is actually a good thing. The Taplfo chip puts out PWM, and the idea was that the slowness of the LDR would make filtering the PWM unnecessary.
Anyway, back to how to go deeper. When the LED is dark, the LDR resistance goes up to say 100k (optimistic), the gain would be 0.1 (10k/100k). When the LED is lit, the LDR drops to something like 1k, so the gain would be 10 (10k/1k). The faster you go, the less time there is for the resistance to rise during the dark periods, and the less deep it gets.
So, it stands to reason that in order to get a deeper effect at low speed, you need an LDR that has a higher off resistance than the NSL-32. In order to get a deeper effect at high speed, you need an LDR that takes less time to transition from on to off.
Or, if you only need it to be deeper at high speed, you can create the illusion of a deeper effect. Set the wave distort so that there is more off time than on time, allowing more time for the LDR to recover to a deeper (and quieter) level. Turn up the gain to compensate for volume loss.
Mike
thanks Mike. So, Could I still replace that 330pf with something higher and it make an effect or could I replace the 10k depth pot with a greater value and it have any effect?
I've got other nsl-32's that I could try but this one works without noise. I've like to keep it in there if possible.
Thanks.
The capacitor is just there to kill the tick. Changing it will have little impact on depth.
Changing the depth control (or any of the controls besides gain) with a higher or lower value will make no difference at all. They are all setup as voltage dividers that vary between 0 and 5v. They feed into the Taplfo chip, which uses software to make the waveforms. Exceeding 5v is not recommended, and I believe that anything over 5v is treated as 5v by the software.
You can use pots of practically any value for most of the controls-- they don't even have to match-- and there would be absolutely no difference in how the controls function.
Unless anyone else has any ideas, trying different vactrols (even of different brand/model) is the best bet, I would think.
Mike
In my experience, it should be possible to get quite a large dynamic range between on and off in square wave mode. The optocoupler trimmer is highly important here. If you decrease the series resistance you should be able to get pretty much completely off at moderate speeds. As Mike notes, decreasing pulse width (wave distort) will help on really fast speeds, but unfortunately getting a tickless, very fast, completely on-off trem with an optocoupler seems to be a bit of a holy grail. I haven't ever seen/heard one.
Thanks for the help guys. I've got a few other opto's which I will swap and then listen. I'll report back soon. Thanks.
Quote from: vassil on March 11, 2012, 10:09:53 AM
Hi all,
Sorry that my next post is not about succeses :).
I finished today tremolo.
In the begining everything was ok (testing out of enclosure). No ticking.
But after some time somefing goes wrong and now tremolo have very loud ticking when waveform is ramp up ,ramp up or square position.
Even if trimpots R13 and R14 is max value (22k), ticking is very loud.
In another positions no ticking but is very very quite "sirene alarm type" whisteling (mayby becose the PCB is not in enclosure).
With 3 difrent type power supply (Boss PSA-120, Harley Benton PowerPlant and one another) is the same symptom.
Capacitor C9 is 1nF. Optocoupler is NSL-32
When i touch TAPLFO pin 3 with a tester or if i replase C2 with biger cap then 22pF, the ticking disapere but waveform sound to (just clean sound).
I replaced C1 and C2 (22pF) caps with a newer same value. But this useless.
I will try next things:
1. Replace optocoupler
2. Replace crystal
3. Is the possible that TAPLFO is some way was damaged?
Any another recomendation.
Tnx.
1, 2, 3 not help.
I found solution for
remove ticking. Maybe its crazy but it works.
I solder together R4 and R5 pins (red mark on pic.).Those that are closer to TAPLFO ICs.
Any explanation for that?
(https://lh3.googleusercontent.com/-hy0pfyxNNiU/T2IvEO1kgVI/AAAAAAAABkU/yR_96eT1ifs/s800/Solution.jpg)
Quote from: vassil on March 15, 2012, 02:10:25 PM
I found solution for remove ticking. Maybe its crazy but it works.
I solder together R4 and R5 pins (red mark on pic.).Those that are closer to TAPLFO ICs.
Any explanation for that?
Looks to me like those two resistors connect to pin 12 (waveform) and pin 13 (tempo).
I can't imagine that your waveform and/or tempo knobs are functioning properly after that.
Mike
Quote from: .Mike on March 15, 2012, 02:42:32 PM
Quote from: vassil on March 15, 2012, 02:10:25 PM
I found solution for remove ticking. Maybe its crazy but it works.
I solder together R4 and R5 pins (red mark on pic.).Those that are closer to TAPLFO ICs.
Any explanation for that?
Looks to me like those two resistors connect to pin 12 (waveform) and pin 13 (tempo).
I can't imagine that your waveform and/or tempo knobs are functioning properly after that.
Mike
I will do some video demo and i post here. But it takes some time.
Then you can evaluate, do my tremolo work properly or not.
Mike you was right. Waveform and tempo func. not work properly on some positions.
When i change waveform, then its impacts also tempo.
So I'm reporting back after trying out different photocells and the NSL-32sr3 solved my depth problem completely and didn't add any ticking BUT when the signal flows through it there is slight buzz/hum that comes in and out with the pulse of the trem. while playing the buzz isn't very noticeable but without playing its very noticeable. any ideas to fix that issue. If I can get that buzz out then it'll be perfect!
Thanks.
Quote from: Johnny B on March 09, 2012, 12:28:04 AM
I built the circuit with C9 at 1nF rather than 330pF and had absolutely no problem with ticking.
I was wrong. :( I didn't notice the ticking at first, but having played with the tremolo more, I now realise that I have ticking in square wave mode, even with the pedal switched off. I have wired the pedal as per the wiring diagram in the build instructions but would like to do the switching mod described by Taylor on page 3 of the thread.
Unfortunately, the link on page 3 doesn't work and I can only download a low res version of the diagram at http://img820.imageshack.us/img820/6872/taptempotremalternateby.th.jpg (http://img820.imageshack.us/img820/6872/taptempotremalternateby.th.jpg)
Taylor, could you please repost the link for the hi-res version of the diagram. Many thanks
Strange, the link is working for me. Are you sure?
http://imageshack.us/f/820/taptempotremalternateby.jpg/
It does open up some pop-ups, so if you have popup blocker on, you may not be able to view it. The next time I'm at my other computer, I will add the alternate wiring to the build document and add it to the musicpcb website.
Quote from: Taylor on March 19, 2012, 02:58:10 AM
Strange, the link is working for me. Are you sure?
http://imageshack.us/f/820/taptempotremalternateby.jpg/
It does open up some pop-ups, so if you have popup blocker on, you may not be able to view it. The next time I'm at my other computer, I will add the alternate wiring to the build document and add it to the musicpcb website.
I have pop-ups enabled from imageshack.us, but all I get is a grey square. Perhaps once you have updated the build document, you could post the link on this thread. Many thanks for your support, Taylor.
Quote from: Johnny B on March 19, 2012, 03:22:34 AM
Quote from: Taylor on March 19, 2012, 02:58:10 AM
Strange, the link is working for me. Are you sure?
http://imageshack.us/f/820/taptempotremalternateby.jpg/
It does open up some pop-ups, so if you have popup blocker on, you may not be able to view it. The next time I'm at my other computer, I will add the alternate wiring to the build document and add it to the musicpcb website.
I have pop-ups enabled from imageshack.us, but all I get is a grey square. Perhaps once you have updated the build document, you could post the link on this thread. Many thanks for your support, Taylor.
Taylor, I managed to download on my home computer so I think the problem must be a block on the office network. It would be nice, however, to have the build document updated.
Many thanks for all your assistance :)
If I wanted to, could I use this as a CV pedal? would I be able to simply attach a jack to the positive leg of the LED to have a CV output?
No, because the signal there is a PWM signal, not an analog LFO. The optocoupler filters the signal into an LFO. You'd need to filter the signal either using the filter circuit in the TAPLFO datasheet, or still using the optocoupler but running a DC voltage through it.
Quote from: engineelite on March 18, 2012, 12:14:12 AM
So I'm reporting back after trying out different photocells and the NSL-32sr3 solved my depth problem completely and didn't add any ticking BUT when the signal flows through it there is slight buzz/hum that comes in and out with the pulse of the trem. while playing the buzz isn't very noticeable but without playing its very noticeable. any ideas to fix that issue. If I can get that buzz out then it'll be perfect!
Thanks.
I suspect the buzz/hum is just the noise in the system being amplified and switched through the tremolo. Try shorting the input to ground and see if you still have the buzz/hum on the output.
I pulled out my oscilloscope and signal generator today to try to solve my ticking problems. I previously rewired the switch as per the diagram on page 3 of this forum and that got rid of the tick when the tremolo is switched off. I also wired my input, output and wire from R10 to switch with screened cable and earthed the screen at one end only.
The scope clearly showed that the click is generated on the negative edge of the output waveform as the tremolo switches off. The front edge rises quite slowly but the back edge falls off sharply. This appears to be in contradiction to the NSL-32 data sheet which shows rise time as 3.5ms and fall time as 500ms. I suppose the tick is generated by the falling edge overshooting at hitting the 0V line. What really had be fooled was that the next door neighbour's electric fence was shorting to earth and generating a click in my amps! :icon_confused:
Anyway, I have the external LED pot (25k) set at max resistance (fully anti-clockwise) and my super-bright blue LED is plenty bright enough. I turned down the pot driving the NSL-32 LED anti-clockwise until the click substantially disappeared. This leaves me with unity gain at about half way on the off-board mounted 50k volume pot. I think I sacrifice some depth, particularly at faster speeds, but I'm reasonably happy with the pedal set up now and the ticking, if any, is not noticeable. ;D
Taylor, I must compliment you on a brilliant design. I really can't think of anything else you could want a tremolo to do. I lent mine to a professional muso who works at a local music store last week and he was blown away by it. It A/B ed it against a Voodoo Labs tremolo and said that apart from all the additional features on the TTT, the TTTs tone way far superior - warmer and more transparent. So thanks and well done, Taylor. :icon_smile:
which opto is better the NSL-32, the NSL-32R2 or the NSL-32R3?
Quick question.. Just wondering how (considering ticking issues and what not) to add 2 LEDs that do the exact same thing (for a blinking eyes kind of effect). :o Would I solder both LED's in parallel to the 2 pads? I remember reading that a few guys were troubleshooting ticking issues and by taking out the LED, I believe, they got rid of it. I'm hoping this is do-able without causing any extra issues.
Thanks in advance.
You probably want to connect the LEDs in parallel, just as in the schematic. Each LED and its current limiting resistor (trimpot in this case) should be connected between 5v and the transistor.
The transistor used for the LEDs is to protect the PIC, which can only source 20mA current. It should be able to handle all the LEDs you need. I was concerned about possibly damaging the PIC by pulling too much current when I put together the VCLFO tremolo (which is the basis for the app note schematic for the VCLFO tremolo, the TapLFO, and eventually this great project). I asked for the simplest solution, and that's what I got. An EE friend of mine drew it up on a napkin... heh!
Of course, the more LEDs you have, the more likely you are to have ticking as they turn on and off. Definitely use superbright LEDs.
:)
Mike
I fixed everything the pedal is super great! BUT when i put it in the enclosure something went wrong and the pedal started smell really bad!! I found out that the 10 Ohm res. was burnt :( I replaced it, I replaced the 78L05, the 330 nF, the TL072 but still nothing!!
I don't know where to go next.
The symptoms are:
-The led works perfectly and changes rate as I tap or move the pot knobs
-With polymeter I found out that the ground(-) of the audio out makes a circuit with the (+) of the audio out. How is this possible?! When I touch the ground(-) with my finger I don't get any sound from the amp.
Any suggestions? what should I try to replace next?The photocoupler?
The 10-ohm resistor is optional, and can be replaced with a jumper. If it burnt, though, it's because something pulled way too much current through it. Since it happened when you put it in the enclosure, I would suspect a short, like a wiring error.
If the LED is flashing, it is likely that the regulator is feeding proper power to the Taplfo, which appears to be functioning properly.
Does it pass signal in bypass?
Mike
no, absolutely no sound in bypass
It's sounding more and more like a wiring error on your build.
Assuming you are wiring it for true bypass, not getting signal in bypass is a problem. That should be debugged first, since the pedal is highly unlikely to work if it can't pass signal in bypass.
Mike
Hi Mike!
thanks for your help!
Perhaps I didn't explain my situation really well (I just don't like writing long posts in fora)
- I built the pedal
I put it on a piece of wood for testing
It played perfectly
I prepared the enclosure
I put everything on place
Then, trying to close the enclosure I squeezed it too much and probably some "naked" parts of the circuit touched each other creating a circuit.As a result too much current passed through the 10 Ohm res. and burnt it.
Obviously it burnt some other parts too in the audio side of the circuit (the TAPFLO part seems to work fine :)))
I changed some parts(10 Ohms, the 78L05, the 330 nF, the TL072 ) with no success. So I am asking which part to replace next :((
The symptoms are:
-The led works perfectly and changes rate as I tap or move the pot knobs
-With polymeter I found out that the ground(-) of the audio out makes a circuit with the (+) of the audio out. How is this possible?! When I touch the ground(-) with my finger I don't get any sound from the amp.
-I get no sound whatsoever.
Should I change the photocoupler? Is it involved with the audio part of the circuit?
Thanks!
Quote from: fatecasino on March 23, 2012, 10:53:30 AM
Obviously it burnt some other parts too in the audio side of the circuit (the TAPFLO part seems to work fine :)))
Maybe, maybe not.
Beyond the TL072, there isn't much to the audio path. We're talking 3 capacitors and 5-6 resistors. You could replace the whole thing and it probably wouldn't make a difference, since...
...if your pedal does not pass sound in bypass, it most likely has a wiring error that needs to be corrected.Quote-With polymeter I found out that the ground(-) of the audio out makes a circuit with the (+) of the audio out. How is this possible?!
If the signal and ground of your audio out jack are connected, there most likely is a wiring error that needs to be corrected.
If this were my build, I would separate it out. Remove the tremolo circuit from the enclosure. Hook it up via a breadboard to make sure it works. If it doesn't work, debug it before moving to the next step, which would be...
Get the offboard stuff working without the tremolo circuit. Take you enclosure, put in the switch and two jacks. Plug your guitar in. Make sure you get signal passing through, and when you push the switch, the signal stops.
Then put the known working effect in the enclosure with the known working bypass.
:)
Mike
Hi all,
I am planning to build TTT and I am wondering if I could use my own fixed preset(s) (set with trimmers) for tempo, depth and other controls?
I guess that this needs some relays (or analog switching ICs) which are controlled using a switch (probably a stomp switch).
Do you have any idea what will happen when the switch is activated and those preset settings are sent to circuit, are there possibilites that some settings are not sitting in?
And what about noises when switching control pads from one pot set to another?
MPV
Seems like a fine idea to me.
Quote from: mpv on March 24, 2012, 06:23:11 AM
Do you have any idea what will happen when the switch is activated and those preset settings are sent to circuit, are there possibilites that some settings are not sitting in?
I'm not sure what you mean by this - could you rephrase it?
QuoteAnd what about noises when switching control pads from one pot set to another?
MPV
I wouldn't expect any noise, since the pots are not directly connected to the audio, don't draw much current, and some minor discontinuity in the waveform should not be an issue. I have swept the multiplier while playing quite a bit - no issues there. But if your setup involves switching you will need to look closely at any chance of the pot inputs floating momentarily, and make sure you take that into account when designing your switching. Also, this is probably obvious, but if you have multiple presets active at once, the voltages will add and you'll get a different setting than if either one of them were active alone.
Quote from: Taylor on March 24, 2012, 06:36:00 AM
Seems like a fine idea to me.
Quote from: mpv on March 24, 2012, 06:23:11 AM
Do you have any idea what will happen when the switch is activated and those preset settings are sent to circuit, are there possibilites that some settings are not sitting in?
I'm not sure what you mean by this - could you rephrase it?
I mean could there be a situation where some "new" settings will be ignored when switching from one pot set to another?
Quote from: mpv on March 24, 2012, 06:56:21 AMI mean could there be a situation where some "new" settings will be ignored when switching from one pot set to another?
The way the TapLFO works is via a control voltage. Each setting-- tempo, waveform, etc-- is set based on a voltage being fed into the TapLFO chip. Voltage goes into chip, software within chip evaluates voltage, software within chip alters LFO based on the voltage.
If a voltage between 0 and 5V is sent to the TapLFO, the settings WILL be picked up. If the settings were not picked picked up by the TapLFO, then the TapLFO would be malfunctioning.
You can feed the TapLFO voltages created by potentiometers, fixed resistors, or even another LFO (as long as it is between 0 and 5V).
:)
Mike
I recently had the problem that my tempo footswitch no longer functioned. I can tap the tempo, it works for 3 cycles and then it goes back to the pot setting.
Any idea what could cause this? The trem worked fine before. Only thing I know that could have triggered it is a short circuit I had due to a daisy chain outlet touching ground.
Should I reprogram my IC?
Quote from: Valoosj on March 24, 2012, 02:29:52 PMShould I reprogram my IC?
I can't imagine that reprogramming the IC would do anything to fix the problem. I suppose corruption is possible, but unlikely. Maybe you got hit by the solar flare a couple weeks back. :P
I would suspect everything connected to pin 13, the Rate CV.
If, for example, there is an intermittent connection to the pot that causes the voltage being sent to the TapLFO pin 13 to vary more than whatever tolerance is built in to the software, it would kick out of tap tempo mode, and back into regular mode.
Stick a multimeter on the pin 13. Tap in a tempo. Move the wires around. Check for variance. It should remain stable, and any change will kick it out of tap tempo mode.
The only other thing I can come up with is that maybe the 5V output is not stable. The 5V regulator feeds the rate pot. If that 5v varies up and down, then the voltage sent from the rate pot to pin 13 would also vary, kicking it out of tap tempo mode.
That's where I'd start. :)
Mike
Quote from: .Mike on March 24, 2012, 12:12:54 PM
Quote from: mpv on March 24, 2012, 06:56:21 AMI mean could there be a situation where some "new" settings will be ignored when switching from one pot set to another?
The way the TapLFO works is via a control voltage. Each setting-- tempo, waveform, etc-- is set based on a voltage being fed into the TapLFO chip. Voltage goes into chip, software within chip evaluates voltage, software within chip alters LFO based on the voltage.
If a voltage between 0 and 5V is sent to the TapLFO, the settings WILL be picked up. If the settings were not picked picked up by the TapLFO, then the TapLFO would be malfunctioning.
You can feed the TapLFO voltages created by potentiometers, fixed resistors, or even another LFO (as long as it is between 0 and 5V).
:)
Mike
Thanks Mike.
Your answer clarified that using switchable pots/trimmers/resistors would work for presets.
Now I just have to find a suitable enclosure in case I choose that the preset trimpots should be externally adjustable through small holes...
I was thinking that 1590BB would be the maximum size for this but now it seems that I need a bigger box...will have to measure the required space for parts again...probably will do a couple of cardboard models of Hammond boxes...
MPV
QuoteIf the signal and ground of your audio out jack are connected, there most likely is a wiring error that needs to be corrected.
Mike you are guru!!
thank you very much for your help, it seemed that the (+)ear of the input jack was touching the back of a pot :(( creating a circuit
Now it's back to life
(http://img442.imageshack.us/img442/3741/p3261841.jpg)
My only problem is that in
bypass mode I get ticking when in
square mode. I followed the advice of page 3 but nothing. I tried all possible combinations of the trim pots and I still have the ticking. Actually turning the trim pots doesn't seem to have any effect on ticking while in bypass mode. Is that a hint for something?
Quote from: fatecasino on March 25, 2012, 11:04:50 AM
My only problem is that in bypass mode I get ticking when in square mode. I followed the advice of page 3 but nothing. I tried all possible combinations of the trim pots and I still have the ticking. Actually turning the trim pots doesn't seem to have any effect on ticking while in bypass mode. Is that a hint for something?
If you have wired the switch as per Taylor's diagram on page 3 (top of R1 shorted to ground through switch when in bypass) then you cannot have ticking in bypass mode. If you have then you must have a wiring error. The ticking is caused by the current surge when switching the LED side of the optocoupler. With pin 5 of the uP shorted via a 10k resistor to ground with the above switching arrangement in bypass mode, then the opto is not switched, so no ticking.
Hey guys, I accidentally broke my tap lfo chip :(.... anyone know where I could purchase another one?
Send me an email at info [at] musicpcb.com and I can set you up with another TAPLFO.
Quote from: fatecasino on March 25, 2012, 11:04:50 AM(http://img442.imageshack.us/img442/3741/p3261841.jpg)
Nice! What kind of finish is that? From a distance, it almost looks like a terrazzo floor, but up close, it looks like a flower pattern. Hmm.
email sent
QuoteNice! What kind of finish is that? From a distance, it almost looks like a terrazzo floor, but up close, it looks like a flower pattern. Hmm.
it's a flower pattern :) :)
Quote from: .Mike on March 24, 2012, 03:30:57 PM
Quote from: Valoosj on March 24, 2012, 02:29:52 PMShould I reprogram my IC?
I can't imagine that reprogramming the IC would do anything to fix the problem. I suppose corruption is possible, but unlikely. Maybe you got hit by the solar flare a couple weeks back. :P
I would suspect everything connected to pin 13, the Rate CV.
If, for example, there is an intermittent connection to the pot that causes the voltage being sent to the TapLFO pin 13 to vary more than whatever tolerance is built in to the software, it would kick out of tap tempo mode, and back into regular mode.
Stick a multimeter on the pin 13. Tap in a tempo. Move the wires around. Check for variance. It should remain stable, and any change will kick it out of tap tempo mode.
The only other thing I can come up with is that maybe the 5V output is not stable. The 5V regulator feeds the rate pot. If that 5v varies up and down, then the voltage sent from the rate pot to pin 13 would also vary, kicking it out of tap tempo mode.
That's where I'd start. :)
Mike
Thanks, my 7805 being dead/faulty seems highly plausible. I did think that a 1N4001 at the 9V input would protect the other electronics from a short circuit. (in this case my 9V of the daisy chain touched ground somewhere)
QuoteIf you have wired the switch as per Taylor's diagram on page 3 (top of R1 shorted to ground through switch when in bypass) then you cannot have ticking in bypass mode. If you have then you must have a wiring error. The ticking is caused by the current surge when switching the LED side of the optocoupler. With pin 5 of the uP shorted via a 10k resistor to ground with the above switching arrangement in bypass mode, then the opto is not switched, so no ticking
.
The solution is the alternative wiring of the diagram in page 3!
I thought the diagram on page 3 was about a second led.
This should definitely be in main pdf of the tap tremolo
Quote from: fatecasino on March 27, 2012, 03:36:14 PM
QuoteIf you have wired the switch as per Taylor's diagram on page 3 (top of R1 shorted to ground through switch when in bypass) then you cannot have ticking in bypass mode. If you have then you must have a wiring error. The ticking is caused by the current surge when switching the LED side of the optocoupler. With pin 5 of the uP shorted via a 10k resistor to ground with the above switching arrangement in bypass mode, then the opto is not switched, so no ticking
.
The solution is the alternative wiring of the diagram in page 3!
I thought the diagram on page 3 was about a second led.
This should definitely be in main pdf of the tap tremolo
Glad the alternative wiring solved the problem in bypass mode. Taylor did say in this thread page 29 on March 19 "The next time I'm at my other computer, I will add the alternate wiring to the build document and add it to the musicpcb website." Guess he just hasn't had time yet.
I really can't stop playing with the tremolo :)
After so much I have 2 quick questions:
1. What does wave distort. really do? I can hear a slight change in the sound, but I don't really understand what it does
2. The tap does not always work..I cannot get the exact tempo I tap. When I tap I can hear some scratch sound coming from the switch. SHould I try to change it?Or do I have some wiring/leak problem?
Thanks!
1. What does wave distort. really do? I can hear a slight change in the sound, but I don't really understand what it does
It should be very noticeable, especially with the square wave.
Have a look at these images to see if it helps:
http://www.electricdruid.net/images/lfo/PDDiagramV9C.gif
http://imageshack.us/photo/my-images/199/wavedistortnoise.jpg
Not sure on your switch question, sorry.
Mike
I Wanted to add a second LED to stay on and blink but it didn't work. Only one LED would blink and the other wouldn't come one. Suggestions?
Hey guys, I finished my build on this really great sounding trem. Great job on this one to everyone who contributed.. especially you Taylor!
I have a quick question tho. I, like others, can dial out just about all of the ticking and it only seems to happen in square wave mode. (I can wipe it ,but the LEDs are way too bright if I do that) I am going to try the 100uf cap across 9v to ground tonight.
QUESTION IS THIS: (forgive my lack of knowledge... I am assuming a 100uf electrolytic cap is what I should use) would I connect the positive lead of the electrolytic cap to 9v and the negative lead of the cap to ground? this makes sense to me, but figured I'd ask before proving myself stupid! ;D
Thanks!
(http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash3/527970_3761162708040_1245738048_3729540_1794613798_n.jpg)
(http://a8.sphotos.ak.fbcdn.net/hphotos-ak-ash3/523890_3761165388107_873381494_n.jpg)
(http://sphotos.xx.fbcdn.net/hphotos-ash3/544571_3761174148326_1245738048_3729544_491713023_n.jpg)
(http://a4.sphotos.ak.fbcdn.net/hphotos-ak-prn1/563743_3761169108200_1245738048_3729543_1370972588_n.jpg)
Cool build!
There is already a 100uf from 9v to ground on the board. I suppose another could help, but I don't expect this to make a huge difference. Have you changed the 330p cap to a 1n?
Thanks for the heads up, Taylor. As I perused it tonight I figured that out, but will try replacing the 330pf with a 1nf cap. This thing sounds awesome!
Quote from: Ultrakd on April 12, 2012, 12:25:46 PM
I Wanted to add a second LED to stay on and blink but it didn't work. Only one LED would blink and the other wouldn't come one. Suggestions?
Anyone know why I wouldnt be able to get the second LED to work?
How exactly do you have the two LEDs hooked up? Are you using the standard bypass or the alternate bypass that was posted in this thread? There are a few ways it could be done depending on the behavior you want.
What I would do, if I wanted one status LED and one tempo LED, is connect an LED directly to the pos and neg LED pads on the board, skipping the switch altogether. That's your flashing LED that will always stay on. Then wire the bypass switch in the standard way to turn a separate LED on and off. That one won't flash but it will show bypass status.
I mean Im wanting 2 leds that stay on all the time and blink. so a total of 3 leds...
Ok so how did you try to do it that didn't work? The way to do that would be to just put another LED and series resistor between 9v and the transistor collector. Without knowing how you did it we can't know whether you just have a cold solder joint or if the way you tried is not going to work.
I put 2 LEDs in the neg and pos place on the board that is for the LED
Any time you have two LEDs in parallel, each one needs its own series resistor. Connect a resistor with one end to 9v, the other end to the positive lead of one of your LEDs, then the negative lead of that LED to the "neg" pad on the board.
so let me see if i get it...they would still be in the same pads just they would both have resistors on them?
Hello everyone. I'm new to the forum, but I've read everything and I'm very excited to get started with this project! I just ordered all the parts to make a few for some friends, but I had a couple questions I was hoping I could get answered before I get started.
The main question I have is about wiring a bypass LED. I understand that the tempo LED is just soldered onto the tabs on the pcb, and I've looked at the diagram from GGG for wiring a bypass LED, but I just don't understand how to incorporate this into the tremolo. Any detailed information on the wiring would be very helpful. Thanks!
Steve
Debugging a freshly bult TTT. I have checked voltages everywhere that should be 5 volts. These instead read a bit more than 7 volts. The 78l05 output is around 7 volts. I hooked a fresh one up to the battery and got the same result.
Anyone seen this?
Any suggestions?
Other symptoms:
Bypass works
LED does not work
Audio path is good up to the optocoupler
Thanks for helping.
What voltage do you read at your 9v input? Any chance you have a regulator with a different pinout than the 78L05?
Input voltage from "9V" battery is about 10.2V.
I believe that it is a standard 78L05. But I also tried it backwards, and got 9v out. So I think I have it in the correct orientation. Three units from the same manufacturer exhibit the same behavior.
Thanks
Until you figure this out, you should remove the TapLFO from the socket (assuming you socketed it).
It has a maximum input voltage of 6.5V, and you risk damaging it if you give it more than that.
Once you figure out the regulator issue, you can put the TapLFO back and try again.
Mike
Thanks for the help, folks.
Voltage problem solved by my Better Half who suggested that my meter was incorrect. After exhausting all other possibilities, I replaced the battery in the DMM.
Voltage out of the regulator now reads 4.96v.
Are these still the symptoms?
Quote from: Radcon on April 29, 2012, 12:28:27 AM
symptoms:
Bypass works
LED does not work
Audio path is good up to the optocoupler
Possible explanations of which I can think:
Transistor could be in wrong - check pinout.
Optocoupler could be in wrong - check the first post of this thread
Bad solder joints in the area between the TAPLFO and the TL072?
But alas, it still does not work.
Voltage readings as follows:
TAPFLO
1. 4.96
2. 0
3. 4.96
4. 4.91
5. 0
6. 0
7. 0
8. 4.96
9. 1.65
10. 3.62
11. 1.24
12. 1.16
13. 2.59
14. 0 ground
TL072
1. 6.37
2. 6.37
3. 6.07
4 0 ground
5. 6.08
6. 6.37
7. 6.37
8. 12.78
Q1
E 0 ground
B 0
C 2.53
Vin 12.89
All pots at approximately 50%
I believe that I have the opto in correctly. Investigating the transistor pinout.
Thanks for the help.
Do these readings shed any light?
Hi there,
The readings look pretty good. Pin 9 should be 2.5V, but that won't stop it working -it only sets the wave distortion. The other pots don't look like 50% always - you've got 1 or 1.5V not 2.5V, but again, this won't stop it working.
Instead, I'd look closely at the crystal and the two caps on pins 2 and 3. If the clock isn't running, the chip is dead. If it is running, you should see a 19.5KHz pulse train on pin 5, the PWM output. If you've got no oscilloscope, run this pin through a flip-flop or divider/counter chip and listen to the output as audio. You'll hear it if it's running. 19.5KHz is too high for my hearing to be sure, so the dividers help.
Tom
You could also test the LEDs by jumpering across the transistor, C to E. The LED should light up. If it doesn't, then the LED and/or optocoupler could be backwards and/or dead, or there could be a problem with the trimpots.
If the LEDs work, you can test the transistor by manually feeding the base a voltage through a 10k resistor (which is what the TapLFO does). If the LEDs don't work, the problem could be with the transistor.
Mike
Thanks for the help, everyone. I am back from a camping trip and returned to the Project.
1. I believe that I had the transistor in backwards. Fixed that, but it still does not work.
2. Unfortunately, I am unable to test the clock as suggested.
3. Both jumping C to E and connecting voltage to the base through a 10k resistor cause the LED to light and signal to pass through. I take this to mean that the transistor, opto, and LED are all now oriented correctly.
I now believe that I have a dead TAPLFO chip. Any opinions to the contrary?
Thank you
Quote from: Johnny B on March 21, 2012, 01:54:47 PM
Quote from: engineelite on March 18, 2012, 12:14:12 AM
So I'm reporting back after trying out different photocells and the NSL-32sr3 solved my depth problem completely and didn't add any ticking BUT when the signal flows through it there is slight buzz/hum that comes in and out with the pulse of the trem. while playing the buzz isn't very noticeable but without playing its very noticeable. any ideas to fix that issue. If I can get that buzz out then it'll be perfect!
Thanks.
I suspect the buzz/hum is just the noise in the system being amplified and switched through the tremolo. Try shorting the input to ground and see if you still have the buzz/hum on the output.
I finally got around to working on my trem again. I shorted the input to ground with all different values of resistors from 1k to 1m and it definitely got alot quieter but there is a tick/buzz still in the background when I'm not playing. Any other suggestions? Thanks.
Maybe someone could post his labeling for the waveform pot?
Would be really helpful... Maybe this could even be included in the project pdf?
Maybe I misunderstand, but the waveforms are included in the PDF.
Sure. Some people placed them around the pot as a scale. Would be great to share that here, because it's not easy to recreate that if all you use is a simple software like photofiltre (that's what I use...)
btw: My pcb arrived last friday - after a long oddysey through german customs authorities. It's really a very high quality pcb. Many thanx for this project!
regards, Immo
I didn't really get too involved with the forum, but I just thought I'd share a couple of my builds and get some feedback. The only thing I had to change was the 330p cap to a 1.5nf (I only had orange drops lying around, but it works!).
Here's mine and one that I built for a friend.
(http://i1098.photobucket.com/albums/g373/stevenholm14/DSC02691.jpg)
Here's another built for a friend.
(http://i1098.photobucket.com/albums/g373/stevenholm14/DSC02647.jpg)
And here's my guts!
(http://i1098.photobucket.com/albums/g373/stevenholm14/DSC02688.jpg)
Quote from: roseblood11 on May 14, 2012, 03:50:12 AM
Sure. Some people placed them around the pot as a scale. Would be great to share that here, because it's not easy to recreate that if all you use is a simple software like photofiltre (that's what I use...)
Here's a 1200 dpi PDF of the wave shapes. You will have to put them in a circle on your own. If your image editing program doesn't open PDFs, let me know what common format would work for you, and I will generate the file. Link (http://goo.gl/HLtJP)
Quote from: sholm14 on May 14, 2012, 07:57:18 AMI didn't really get too involved with the forum, but I just thought I'd share a couple of my builds and get some feedback.
Very nice!
I notice you didn't add the wave distort pot. Just curious-- did you try it and not like it? I think it's one of the best features of the LFO.
Mike
Quote from: .Mike on May 14, 2012, 09:33:26 AM
Very nice!
I notice you didn't add the wave distort pot. Just curious-- did you try it and not like it? I think it's one of the best features of the LFO.
Mike
I guess I just never really thought of putting in the wave distort pot. My first problem is that I wanted to order the enclosures from PedalPartsPlus, and so that was the drilling that I chose. If I do build another, I will for sure try it out!
I have made a waveform labeling just for you roseblood ;)
https://www.box.com/s/31934e0eba281fb5458d (https://www.box.com/s/31934e0eba281fb5458d)
It will fit around a 3/4" knob. To make it fit around a bigger knob you just have to scale it to a bigger size before printing it. I made 3 different versions so it can be used either with a rotary switch, a 270° pot or a 300° pot.
many thanx!
but I hope that it's useful for more people...
@Taylor: Maybe in an updated version of the IC the switching could be simplified? What about this: Omit the waveshape and the multplier pot. Just use the momentary switch connected to "EXP" for both: If only this switch is pressed, it steps through the multiplier settings. If the tap tempo switch is continously pushed down, the switch steps through the wave shapes.
The values could be shown by different kinds of LED's:
http://www.reichelt.de/Flaechen-LEDs/FLED-10X22-GE/3/index.html?;ACTION=3;LA=2;ARTICLE=31470;GROUPID=3015;artnr=FLED+10X22+GE;SID=12T7F2-n8AAAIAAHU0RV4f416968deb1ca8516db9bbfa10a8c213
or nummerical:
http://www.reichelt.de/Siebensegment-Anzeigen/SA-39-11-GN/3/index.html?;ACTION=3;LA=2;ARTICLE=6920;GROUPID=3002;artnr=SA+39-11+GN;SID=12T7F2-n8AAAIAAHU0RV4f416968deb1ca8516db9bbfa10a8c213
Definitely message Tom at Electricdruid.net about your suggestions. He is the designer of the chip, so even if my microcontroller skills were better than they are, I wouldn't have the right to modify the code. But he may be interested in a new version.
My personal preference is that I vastly prefer knobs over stepping through menus, though. I can't stand schemes where a single button controls multiple functions with long-presses, etc. Plus, having the multiplier as a pot control lets you sweep through it with expression control, which is pretty fun. But that's all just my own preference.
Quote from: Taylor on May 14, 2012, 06:40:53 PMPlus, having the multiplier as a pot control lets you sweep through it with expression control, which is pretty fun.
That's a potent argument! ...and one more idea for my build ::)
i just built mine and have a big problem with ticking, should i not have the jacks grounded on the pad that says 'ground'?
also for cv of the pots- do I just have a mono jack, tip connected to center lug and sleeve to ground?
I recommend star grounding to the input jack sleeve. Also try upping the 330p cap to 1n.
If you want CV instead of a pot, connecting that way will work, assuming you have a CV source putting out 0v-5v. If you want both CV and pots active simultaneously, you'll need some resistive mixing. The CV source should have a 10k resistor in series, and the pot should have a 10k coming from its wiper. Then connect the two 10ks together and wire them to where the pot's wiper went previously.
I am pleased to report that I now have the TTT working beautifully. As encouragement (?) to other beginners, I offer the following list of problems which prevented the device from working, along with my thoughts on how to prevent similar problems on my next build:
1. Transistor pinout different than expected - installed backwards (learned how to test).
2. Gain trimpot was bad (test before installing)
3. TAPLFO chip was bad (bad luck, I guess)
4. Wrong value capacitor in the Xtal/ oscillator section of the circuit. (be skeptical of poorly marked items out of the parts bin. Invest in a multimeter with a capacitor test feature)
Thanks again to everyone involved. Great project.
Hi!
I would like to use external tap in /out function also. Connector I plan on using is this :
(http://sigma.octopart.com/9340791/image/CUI-RCJ-012.jpg) It is something similar Cusac tap-a-whirl uses.
Should I connect sleeve pins to the ground of the board, or just TIP pin to the pin 7 of the uC?
I would also like to know what is the max current pin 7 of the uC can handle?
Quote from: Hoffmann on June 13, 2012, 04:39:18 AM
Hi!
I would like to use external tap in /out function also. Connector I plan on using is this :
It is something similar Cusac tap-a-whirl uses.
Should I connect sleeve pins to the ground of the board, or just TIP pin to the pin 7 of the uC?
I would also like to know what is the max current pin 7 of the uC can handle?
Pin 7 is a clock out. Pin 4 is the tap in. I don't see how an RCA jack is going to serve that dual function without extra supporting circuitry. If using that jack for
either pin 7 or pin 4, though, you need the pulses to go between 0 and 5v, and for that you will need a reference-- ground.
Also, since pin 7 is a clock output, it isn't really meant to source current. It's meant to trigger some other circuitry, and that other circuitry should be designed to not need much current at all. Regardless, the max current that any output pin on the TapLFO (16f684) can source is 20mA, hence the transistor driver to protect the PIC on the off chance that the LEDs try to pull too much current.
Good luck! :)
Mike
this is what I ment:
(http://i47.tinypic.com/xb0qkg.png)
I am not sure I need to ground RCA ground pin?
This kind of arrangement can serve as TAP in and TAP out On the RCA connector, depending on the state of the toogle switch.Am I right?
Built mine a while ago and recently repainted the box. I did the rate LED mod that keeps it from ticking in bypass, but otherwise it's stock. This one's still on my board all the time:
(http://jonpattonmusic.files.wordpress.com/2012/05/cardinal-tremolo.jpg?w=300&h=243)
No gut shots since I don't want to open it up ... it's finicky about the exact placement of the board. I probably ought to replace the jacks with low-profile plastic or enclosed jacks to avoid shorting. I wasn't as good at boxing things at the time I built this.
Second version: I added the same driver to the TAP out ( to protect PIC if some external tap device trys to pull too much current from the PIC). review please!
(http://i47.tinypic.com/2liy875.png)
^bump ;)
Quote from: Hoffmann on June 15, 2012, 04:11:03 AM
Second version: I added the same driver to the TAP out ( to protect PIC if some external tap device trys to pull too much current from the PIC). review please!
(http://i47.tinypic.com/2liy875.png)
Either look fine to me. The PICs outputs are pretty robust (20mA max) and I haven't managed to kill one by plugging things into it, so the second version seems a bit belt-and-braces. But if you want to be sure, go for it.
I would ask why include an expensive toggle switch to avoid the need for a second cheap RCA socket? Wouldn't it be easier and more flexible to have separate In and Out plugs? But again, I don't know the whole situation, so you've prob'ly got your reasons...
Tom
Can someone explain the external sync a little? It just hooks up to the tip of a jack? Jack sleeve should be grounded or isolated?
Yes, it just connects to the tip of a jack, and yes, the sleeve should be grounded. It'll accept any voltage input between about 5V and 15V or more. It works best with nice regular square pulses at the sorts of tempos that humans like, though the range is pretty wide (wider than the tempo knob allows).
HTH,
Tom
Thanks Tom. I kind of guessed the tip thing but just wasn't sure if the jack had to be isolated from ground or not. Better to ask then to assume.
So what causes that "clicking" sound when effect is in bypass mode? Is it coupled through a ground plane ( obviously not through power line as it clicks in bypass...) , and can it be avoided some other tehniques other than sending PWM to ground( better isolation of the ground planes- better separation of digital and analog circuitry on the board ect.) ?
'
The PCB has separate ground planes for the sections which are all coupled only at the ground wire. IMHO it can't be decoupled much better short of having entirely separate PCBs. Having built a number of them, and never having an issue with ticking, my best suggestions would be to pay attention to your wiring and lead dress, swap the 330p for a 1n, and get your trims set up correctly. I don't know of any real downside to the alternate bypass on page (3?) if you need to use it.
Hi Taylor,
I have already made your tiny giant amp (which by the way is great! I'll post some pictures soon) and I have now just got the tap trem and the Echo base. Ive ordered and received all my parts and was halfway through making them when I realized I'd bought a surface mount chip version of a 78L05 rather than just the three leg one. Here in England there aren't a great many suppliers of components and delivery charges are always a pain. I was wondering if it would be possible to just wire this chip into the circuit (I know a bit messy, but oh well). The chip has 8 legs; 4 ground legs, 1 V-IN and 1 V-OUT and also 2 NC (im guessing I shouldn't connect these?) Would it be OK to just wire all the grounds together and solder them to the ground and then the IN and OUT as specified on the board?
Thanks for your help.
Yes, that will work if you can manage to do it. You're right that NC means no connection.
The only caveat would be to make sure the part you have can handle similar amount of current, or at least what the PIC draws (maybe .Mike knows that number without having to scan through the PIC datasheet?)
The PIC16F684 operating current is measured in microamps. The PIC feeds a maximum of 0.5mA to the transistor buffer. I can't imagine needing more than 5mA apiece for the LEDs. So, 0.5mA + 10mA + <1mA = 11.5mA max.
By the way, you can order 78L05s from Tayda for $0.09 plus shipping, which shouldn't be more than a buck or two. I think there is a $5 minimum order.
Also, don't be afraid to scavenge. You can probably find a 5v regulator in an old radio, VCR, TV, etc.
Good luck! :)
Mike
Just finished the tap tempo trem build - works like a champ and sounds excellent! I used the alternate bypass routing listed waaayyy back on page 3 along w/ a 2.2nF cap (in lieu of the 330pf) and no ticking here. Thanks Taylor and everyone involved in this!
(http://distilleryimage8.instagram.com/0774caf4cc1a11e1a94522000a1e8aaf_7.jpg)
(http://distilleryimage6.instagram.com/094933accc1911e1a94522000a1e8aaf_7.jpg)
Cool build. 8)
Quote from: Taylor on June 02, 2012, 05:48:09 PM
If you want CV instead of a pot, connecting that way will work, assuming you have a CV source putting out 0v-5v. If you want both CV and pots active simultaneously, you'll need some resistive mixing. The CV source should have a 10k resistor in series, and the pot should have a 10k coming from its wiper. Then connect the two 10ks together and wire them to where the pot's wiper went previously.
Taylor, I have an old optical expression pedal that I'm trying to make work. I have a stereo switching jack wired up such that the wiper switches over from the pot to the CV input when a jack is inserted. 5V and Ground is routed to the expression pedal (tip and sleeve respectively) just as it is to the pot. So, I'm not trying to have both the pot and the expression pedal CV source active simultaneously. I've modified the expression pedal to use an LED instead of a bulb, so current should be minimal. In isolation testing, my expression pedal outputs 0-5V properly, when fed ground on sleeve and 5V on tip. However, when I plug it in, the output is pegged around 2.5V, with very little effect on voltage when I sweep the pedal. Any idea what might be going on? Should I source 5V separately to drive an LED/LDR?
If you can draw a schematic of how you've done it might help to understand. But, as far as I know there are no optocouplers that work like voltage dividers (two separate CDS cells that change resistance in opposition to each other) so I'm not sure how you're dividing the voltage.
Quote from: Taylor on July 16, 2012, 10:26:33 PM
If you can draw a schematic of how you've done it might help to understand. But, as far as I know there are no optocouplers that work like voltage dividers (two separate CDS cells that change resistance in opposition to each other) so I'm not sure how you're dividing the voltage.
In taking photos and drawing up a diagram, I discovered my error. I had the wiper of the pot and the return to the board backwards on my switching jack. I swapped the wires and now my 5V control voltage from my pedal is feeding the tempo input. Two problems now, first of all the sweep isn't very good (I have to get about half way to toe down before the voltage starts climbing). Second, when I heal down, the LDR is very slow dropping back to 0V from 5V. Seem's to take about 3 seconds or more to settle down to ground. Definitely not responsive, compared to twisting the pot back and forth.
Is this an inherent trait of optical expression pedals, or is this just a very old pedal? As I said, I swapped out the bulb for a jury rigged LED, and this thing looks likes it's from the seventies. Maybe it's old tech LDR meant for some other application and a new faster LDR would make a difference. It's one of those shark fin light blocker types.
(http://i1105.photobucket.com/albums/h359/travispike/July2012104.jpg)
The sweep being less than ideal doesn't surprise too much. You could probably play around with some series and parallel resistors on the LDR to get it more ideal - see "the secret life of pots" on geofex if you need some ideas.
LDRs are slow. 3 seconds is pretty extreme, but not entirely surprising. I expect that this would be used as a volume pedal for an organ, where speed might not matter too much for the average family organ. You could try getting a modern LDR with faster response time like the NSL-32 used in this project or the vactec series (datasheets with on and off time are available for both).
Thanks Taylor. I have some used wah shells on the way, which I plan to use for several expression pedal applications, so I think I'll have better solution in the future. A resistive pot will be much more responsive. At one point, I was thinking of reusing an old Morley pedal for the Tap Temp Trem... the footprint of the Morley allows for a nice layout of the additional knobs and would make a great all in one Trem pedal. However, Morley's use optical as well, and I'm not sure if the response is fast enough for these type applications (vibe, trem, phaser speed control).
What is the 330 pF Capacitor for? For some reason, I accidentally ordered a 300 pF cap. Would this impact it tonally?
That cap has to do with the frequency response in the output gain stage. A slight difference in the cap value will not be noticeable, and many people end up using a significantly larger value there if they have ticking when it's built up.
Quote from: Taylor on August 03, 2012, 11:56:16 AM
That cap has to do with the frequency response in the output gain stage. A slight difference in the cap value will not be noticeable, and many people end up using a significantly larger value there if they have ticking when it's built up.
Thanks, was worried for a minute but went ahead and installed it anyway.
Well, I had everything installed and built and wired together...went to plug it in to a 9v DC, about 100-200 mA, and had no sound for a few seconds, then next thing I knew, a resistor started to burn and turn black. I can't remember off the top of my head which one specifically, but just one of them.
I used a TL082 instead of a TL072, could this be the cause of that?
Must have had your diode backwards :icon_eek:
It's probably the resistor in the power supply-- 10 ohms... 100 ohms... I forget.
It is not critical. Replace it with a jumper. Be happy. :)
Mike
I don't think so.
The orientation on the diode matches the way it is shown on the PCB.
It was the 10 ohm resistor.
Well I jumpered it and no problems. But now, I don't get any signal when engaged. I did the alternate switching with the LED soldered directly to the PCB. I decided not to use the Tap feature, so I left those pads open. I have double checked my wiring and everything seems in order.
Oh, I'm an idiot. I took the tap switch out and that's why I have no continuity when engaged. DUH.
I can't for the life of me figure out what is going on.
I have no signal, whether engaged or bypassed. I have even doubled checked my wiring with other finished PCB's shown in this thread, and everything mates. All it does is hum and hum and hum.
If you have no sound whether bypassed or not, the problem lies between your input jack, the bypass switch, and your output jack. Hum tends to point to ground issues. Make sure your grounds are all connected together, meaning the ground on the board, the switch, the power jack and the in and out jacks. Then check the debugging pages stickied at the top of this forum, build an audio probe, and go through the circuit in order to find your problem.
Well, part of it was I had the polarities on the DC jack wrong.
Now the LED stays lit all the time, so I'm guessing I have the switch wired wrong.
For the alternate switching method (Where the LED is permanently wired to the board), should the switch be wired like this?
(http://i50.tinypic.com/2rddedl.jpg)
Forgive me if I said the wrong value for the resistor there.
I have never used 3PDT switches and am still somewhat of a noob at this.
So i built the Tremolo yesterday and plugged it up and I get ticking but no signal through I've checked all my connections all day to day it worked for a couple seconds then it quit again I have no clue what to do now, thanks in advance
Joey
Check the stickied threads on this forum regarding debugging and "what to do when it doesn't work."
So I just built this (after putting it on the to do list for a couple years) and it sounds great. I know some others in this thread mentioned trying the external sync function so I'm wondering if anyone can report a success? I have a semi-success to share:
I thought it would be cool to get the LFO to sync to my MPC sequencer. The MPC doesn't have any CV out but it does have an audio out and I do have snare drum samples. 8) I set a snare sample to play pretty loud on quarter notes. I connected the tip and sleeve of the MPC's output to the two terminals meant for the tap switch. SUCCESS!!!! Kind of...
The LFO definitely follows the tempo changes. It's not perfect but it's close. As I speed up the tempo of the mpc the tremolo follows with it. There are a few issues however.
1. The LFO seems to be out of phase with the tremolo. Looking at the PIC datasheet from Electric Druid this makes sense. From the datasheet:
Quote
The TAP TEMPO input accepts negative-going 5-0V pulses, and times the period between the falling edges of consecutive pairs of pulses to set the frequency. If another device provides a 0-5V clock signal, this can be fed to the TAP TEMPO input and the LFO will synchronize to the clock.
I know the PIC also resets the phase when receiving a "tap" so it seems that the PIC is setting the phase at the
end of my snare pulse as opposed to the beginning.
2. On the same page of the PIC datasheet (the last page) Electric Druid outlines a small transistor circuit which I assume acts as some sort of buffer for the incoming CV pulse. Has anyone built this? I don't know for sure that my MPC was outputting the right voltage so I'm considering trying this (it's just a standard line level output).
3. With the MPC output wired directly to the tap switch of the LFO it was, in effect, like constantly tapping the switch. I don't know if this is the best option. I'm considering trying a momentary NO switch to only let the pulse through when I step on it to see if this cleans things up.
4. Also, what is Pin 13 supposed to be used for and how does this differ from the "tap tempo input" (pin 4). Should I be sending my pulse to Pin 13 instead?
I'm open to any suggestions at this point. Also I can confirm that the VTL5C2 opto works very well.
Ian
I have an idea I'm toying with in the simulator. Because the PIC expects a negative pulse (as opposed to the positive one the sequencer is putting out). Is the solution as simple as using an inverting opamp in front of the pic? Or would I have to inject a certain amount of DC offset to make the pulses drop down to zero as opposed to negative voltage. Let me know if I'm making no sense.
Well, I can answer one of your questions...
Quote from: ianmgull on September 03, 2012, 10:09:24 PM
4. Also, what is Pin 13 supposed to be used for and how does this differ from the "tap tempo input" (pin 4). Should I be sending my pulse to Pin 13 instead?
The LFO can be used in tap mode, or manual control mode. Pin 13 is for the manual rate knob. It accepts 0-5v DC (0 = slowest, 5v = fastest). If you are using tap mode, the rate knob does nothing. BUT, as soon as you touch the rate knob, it kicks out of tap mode, and the speed is based on the rate knob setting. Sending pulses to pin 13 would not achieve the desired result.
I'm not sure on the rest. I am looking for the easiest way to sync two TAPLFOs. I finally bought a few PICs, and plan on doing some testing once I figure out how to program them. It's on the list. If you find anything on syncing two TAPLFOs, please let me know.
Mike
Thanks for the reply Mike. I'll definitely post here if I figure anything out.
What you said about pin 13 makes sense. I didn't realize that was the CV pin.
I'm also interested in chaining a few LFO's together eventually. What was your plan for doing this? Pin 5 and 7 both look like candidates for sending clock sync. I assume 5 is a digital pulse and 7 is CV? Did you plan on using the transistor buffer circuit for the 2nd PIC's tempo input?
Ian,
I PMed you about this, so we don't crap on Taylor's build topic. :)
Mike
No worries about that, Mike. :) Life circumstances have precluded me from following closely, but I bet others are interested in reading what you guys are cooking up. If you don't want to post here, consider starting a thread so others ca n follow.
Thanks for the info Mike, no new developments on the LFO sync...
Ok I've got an unrelated question.
Has anyone ever noticed a clock glitch in the lfo cycle? What I mean is every 20 seconds or so the clock has a bit of a hiccup and it's as if there are two positive cycles in a row.
I had that problem back in 2009 when I was working with the VCLFO. I couldn't figure it out, but Tom spotted it right away:
QuoteYou've got the Step Rate CV input tied to Vdd, which will enable the Sample-and-Hold feature. This stepping wouldn't be immediately obvious with a square wave output, but occasionally it might cause it to apparently miss a pulse. Tie its 1K resistor to 0V instead.
You probably wouldn't hear the steps at all on other waveforms since the step rate is at maximum (which is about 25Hz IIRC) and the LDR will provide enough smoothing to hide them.
Granted, that doesn't specifically apply to the TAPLFO, but the same concept may apply. Check the datasheet, and make sure that pins that need to be held at ground are at ground, and pins that need to be held at 5v are held at 5v.
:)
Mike
I almost understand what you mean ;D
I only have four pots on my build (tempo, waveform, multiplier, depth). All are getting 5v on lug1 and 0v on lug3 (with the exception of multiplier because of the 3k6 resistor).
All of my CV pins seem to be getting proper voltage. I'm just confused about what you meant by connecting the 1k resistor to 0v.
Looking at the schematic I see a 1k resistor in series between pin 13 and the wiper of the tempo pot. Are you saying this resistor connects to ground? I'm using Taylor's beautiful PCB if it makes any difference.
Thanks!
I apologize if these questions have been covered. I have read through the thread that started this project and got through part of this thread. I like everything I'm seeing so far. There are two questions I can think of so far.
- First up should be the simplest... How is the pcb supported? Is it from the top three pots? Is that it?
- I have a DD20 and I planned on having it modded so the tempo signal can be sent from it to anything else I wanted... such as a tap tremolo. I've been thinking I'd get a Seymour Duncan Shape Shifter but after reading through so much on this pedal I think I'm leaning towards this one. But I read that the tap tempo takes the first two taps and that's it. If my DD20 is sending a constant signal will this pedal still work? I was hoping to be able to keep the two in time together.
If these two have been answered already just tell me to keep reading and I will ;D
Quote from: dean owens on September 08, 2012, 11:46:17 PM
I apologize if these questions have been covered. I have read through the thread that started this project and got through part of this thread. I like everything I'm seeing so far. There are two questions I can think of so far.
- First up should be the simplest... How is the pcb supported? Is it from the top three pots? Is that it?
There are no mounting holes on Taylor's board; it was designed to be supported by PCB mount pots.
Quote from: dean owens on September 08, 2012, 11:46:17 PM
- I have a DD20 and I planned on having it modded so the tempo signal can be sent from it to anything else I wanted... such as a tap tremolo. I've been thinking I'd get a Seymour Duncan Shape Shifter but after reading through so much on this pedal I think I'm leaning towards this one. But I read that the tap tempo takes the first two taps and that's it. If my DD20 is sending a constant signal will this pedal still work? I was hoping to be able to keep the two in time together.
If these two have been answered already just tell me to keep reading and I will ;D
Trying to sync the LFO to an external source is what I've been trying to figure out as well. Have you found a way to get clock pulses from the DD20 yet? I'd be curious if so. Below is a video I made trying to sync the tremolo to my MPC 1000. It works better than expected but the square wave is out of phase. I tried using an inverting op-amp to flip the polarity but had no luck.
Quote from: ianmgull on September 09, 2012, 12:03:47 AM
There are no mounting holes on Taylor's board; it was designed to be supported by PCB mount pots.
Ok, that's what I thought.
Quote from: ianmgull on September 09, 2012, 12:03:47 AM
Trying to sync the LFO to an external source is what I've been trying to figure out as well. Have you found a way to get clock pulses from the DD20 yet? I'd be curious if so.
Me? No. Pedals are somewhat new for me. I've been building amps for years but never really messed in pedals. I was thinking about having my DD20 sent off to this1smyne. I was looking on this (http://this1smyne.com/pedal-mods/) page and saw this mod. Before that I was just thinking of making a tap tempo with two outputs to send to the DD20 and the tremolo.
It looks like you should be able to sync the DD20 to the Tap LFO. The question is if the pulse is positive or negative. At any rate you'll likely need to build the transistor circuit on the last page of the data sheet below:
http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf)
Quote from: ianmgull on September 09, 2012, 04:29:05 PM
It looks like you should be able to sync the DD20 to the Tap LFO. The question is if the pulse is positive or negative. At any rate you'll likely need to build the transistor circuit on the last page of the data sheet below:
http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf)
Thank you. That seems easy enough. Now how do I find out if the pulse is + or - before spending the money and having it modded?
Another very simple question (at least I assume it's simple since I can't find where anyone else asked it)... Does the tap switch need to be normally opened or normally closed? I ask because in the meantime I was just going to build a tap box for both my DD20 and the tremolo and the DD20 needs a NC switch.
I finished my pedal this morning and plugged it in and to my alarm I saw no flashing led...but smoke coming from my board! Now to be fair I was not paying attention and accidentally plugged in a Line 6 pod power supply into my pedal that was sitting around next to my pedal board rather than one of the leads from my power brick. When I opened up the pedal I saw that the 10R resistor right next to the diode/rectifier was the culprit in the smoke show.
Any ideas on what the problem might be? Or do you think it was my mistake in plugging in the line 6 power supply that caused it.
Also, I do have bypassed signal coming through my pedal. But no trem and the led is not lighting up...but all of that is to be expected I guess with a fried resistor.
Is the power supply 9vdc? Is it wired so that the negative terminal goes to the same place as the negative terminal on your pedal (most people use center negative but it can be iether way as long as they match)?
Quote from: Taylor on September 16, 2012, 03:39:03 PM
Is the power supply 9vdc? Is it wired so that the negative terminal goes to the same place as the negative terminal on your pedal (most people use center negative but it can be iether way as long as they match)?
The line 6 power supply is 9vAC instead of DC I believe. Do you think that is what burned up that resistor?
My center along with the gnd from the board, the sleeve from the out jack and the gnd from the bypass all star on the sleeve of the input jack. Is this wrong?
Sorry for all the questions...I researched for hours to build this pedal as it is my first one. I know it has been said it is not a great beginners pedal and I know these are probably silly questions...but the truth is I just really wanted the pedal, and the only way I knew of to get it was to build it.
You need to power this pedal (and pretty much all DIY projects) with 9vDC. So that's why your resistor burned up and you may have damaged other components like the PIC. I haven't really studied what happens when you plug AC into a circuit like this - I bet RG could tell us in great detail though.
Try a DC power supply and see what happens. You may only need to replace that resistor and possibly the 4001 diode.
By the way, not to discourage you from DIY, but there are tons of people who sell this pedal. Just google tap tempo tremolo and like 95% of the boutique ones (and even a couple made by slightly bigger companies) are either this exact circuit or a slight variation of it, with the same code and everything.
Thanks!
I kinda liked the sense of accomplishment after building it. That is until it started smoking...and it turned into a sense of despair. Haha. I think I might have another go at another pedal in the future. I feel like I learned a lot with this one...and all in all it has been fun!
So I just finished building my Tap Tempo Tremolo and wanted to test it before I started installing everything in to the enclosure I have. Basically, I wired up the 3pdt switch as is showing in the diagram from the musicpcb.com site. The ground lines are as such...
-GND line from pcb to Line out ground (sleeve)
-Ground from 3pdt switch (as shown in diagram) to Line In ground (sleeve) then to 9V input ground (sleeve)
-LED isn't coming on.
When I turn on the pedal I get some buzzing intermittently and had some ticking (about 60bpm) that would eventually go away. The internal pots for the LED and octupler as well as the internal gain pot did nothing. No signal coming through whether the pedal is on or off. So basically, it doesn't work. I'll post a pic in a few minutes but I wanted to at least get these notes on here asap so I didn't forget anything. This is my first pedal build but I do have a few years of experience working on arcade and pinball pcbs so I know my soldering is good. Not always pretty... but good. There are no solder bridges anywhere or anything like that.
I'm considering going to one of the 2 LED layouts that have been mentioned in this thread because 1) 2 LEDs are better than 1 :) and 2) It would help take care of some of the ticking issues once I get this thing working. Anyways, here are some pics. Please help. :)
(http://i38.photobucket.com/albums/e107/bongoben/IMG_3891_zps1f2d08e6.jpg)
(http://i38.photobucket.com/albums/e107/bongoben/IMG_3892_zps6fc1453d.jpg)
(http://i38.photobucket.com/albums/e107/bongoben/IMG_3893_zps8d3d8d7c.jpg)
Since there's a few people here having trouble with the build, here's a few ideas for debugging. I'm assuming you're using the circuit from:
http://musicpcb.com/wp-content/uploads/2010/09/Tap-Tempo-Tremolo-build-PDF-updated.pdf
1) Is the +5V supply ok on the PIC? (Pin 1 is +5V, pin 14 is 0V)
2) Is there any PWM output?
The output LED should be doing something (showing the LFO output) but if t isn't you can check with a 470R resistor and an LED direct from the PWM output on Pin5. If it's ok there (e.g. test LED lights), the transistor might be dead.
3) If the power is ok and the PWM is ok, the audio path must be the problem.
With the tremolo switched in, check that there's audio at the output of the first buffer on pin1 of the TL072. If you can hear the signal there, but you can't hear it at pin 7, the problem is the second stage, the actual tremolo - that might be the vactrol, or one of R15/C9. If pin 7 is ok, then the problem is C10 or R16.
4) If the power is ok, but the PWM isn't working, then the PIC is not working.
This could be because the clock isn't running correctly - check the 22pF caps and the crystal. It is also sometimes caused by open CV inputs. Check soldering/wiring of pots. Similarly, if the 'Next multiplier' input on pin 8 is left floating, the chip does all sorts of weird stuff - speeds up and down, goes wobbly, etc
If it doesn't work immediately, don't worry. PICs are pretty tough. I've managed to fry one or two (but even then mostly only one IO), but I've also got away with stuff that I fully expected to totally cook the chip.
Ok, that's about all I can think of for starters. Good luck!
Tom
I couldn't get rid of ticking in square wave mode. Then I read that adding a cap from the transistor's emitter to base (=gnd) could help. I tried values from 10nF to 1000µF. 10µF or 22µF worked best, higher values smoothed out the waveform too much. Is it really that simple? Or are there any drawbacks to this solution?
Ok my pedal has been working till now. Now its ticking with the pedal in bypass. The only modes it doesnt tick is in, Sine and Lumps. I need some help cause I love this pedal but it keeps giving me problems and I can figure out why.
Use shielded wires for all input- / output connections. Keep these wires as far away as possible from all wires to pots that shape the waveform or go to the rate LED.
This is still unanswered:
QuoteI couldn't get rid of ticking in square wave mode. Then I read that adding a cap from the transistor's emitter to base (=gnd) could help. I tried values from 10nF to 1000µF. 10µF or 22µF worked best, higher values smoothed out the waveform too much. Is it really that simple? Or are there any drawbacks to this solution?
I still don't understand exactly, how the ticking finds it's way into the audio signal (when the pedal is turned on).
Quote from: roseblood11 on December 02, 2012, 09:59:19 AM
Use shielded wires for all input- / output connections. Keep these wires as far away as possible from all wires to pots that shape the waveform or go to the rate LED.
what Idont get though is this is a new issue it never happened before.
Quote from: roseblood11 on December 02, 2012, 09:59:19 AM
Use shielded wires for all input- / output connections. Keep these wires as far away as possible from all wires to pots that shape the waveform or go to the rate LED.
If the shielded wires dont work what should I try next?
Check page 3 I think for the alternate wiring diagram. Might help.
Quote from: ElectricDruid on September 24, 2012, 05:27:53 AM
Since there's a few people here having trouble with the build, here's a few ideas for debugging. I'm assuming you're using the circuit from:
http://musicpcb.com/wp-content/uploads/2010/09/Tap-Tempo-Tremolo-build-PDF-updated.pdf
1) Is the +5V supply ok on the PIC? (Pin 1 is +5V, pin 14 is 0V)
2) Is there any PWM output?
The output LED should be doing something (showing the LFO output) but if t isn't you can check with a 470R resistor and an LED direct from the PWM output on Pin5. If it's ok there (e.g. test LED lights), the transistor might be dead.
3) If the power is ok and the PWM is ok, the audio path must be the problem.
With the tremolo switched in, check that there's audio at the output of the first buffer on pin1 of the TL072. If you can hear the signal there, but you can't hear it at pin 7, the problem is the second stage, the actual tremolo - that might be the vactrol, or one of R15/C9. If pin 7 is ok, then the problem is C10 or R16.
4) If the power is ok, but the PWM isn't working, then the PIC is not working.
This could be because the clock isn't running correctly - check the 22pF caps and the crystal. It is also sometimes caused by open CV inputs. Check soldering/wiring of pots. Similarly, if the 'Next multiplier' input on pin 8 is left floating, the chip does all sorts of weird stuff - speeds up and down, goes wobbly, etc
If it doesn't work immediately, don't worry. PICs are pretty tough. I've managed to fry one or two (but even then mostly only one IO), but I've also got away with stuff that I fully expected to totally cook the chip.
Ok, that's about all I can think of for starters. Good luck!
Tom
Tom, Thanks for the trouble shooting advice. I do certainly appreciated the step by step!
The issue i'm having with my build is that i've got no signal at all coming through the effect's first buffer. I've redone my wiring now completely a seperate time but no change in the problem which leads me to believe it is in fact a faulty part or issue with the circuit board. I've got all the parts connected and i get the tap LED function going on. The PIC is doing its job for sure, The LED speeds up and slows down with the knobs and tap switches like it's supposed to but no signal through the pedal at all. I tapped the output wire to the first pin on the TLO72 with no signal at all. I'm getting good voltages on the PIC but it's weird. I get a pop whenever i touch the output to the 1st pin on the opamp but other than that there's nothing. it sounds like a capacitor is discharging when i bypass it. It'll pop then if i touch it again there's no noise, but if i wait a second it will pop again. This probably isn't very descriptive...but that's the problem i'm experiencing. Any ideas? I'v also switched out the opamp for a known working one to see if that was the issue. no change.
Does your audio probe have a cap in series? If not it will pop when you touch biased signals.
Are you certain your optocoupler is in the right way?
If you really genuinely think it's a fault in the board, I would of course replace it. But in my experience these (and faulty opamps) are exceedingly rare in comparison with errors that I have missed.
To be clear, you have signal at the input of the first buffer but not at the output?
The capacitor fixed the popping...Noob move.
I still dont get any signal past the input though. If the pedal has no power i can use the first pin on the opamp and get signal out of it but with power on all it does is slightly hiss with some radio interference. I cant pick up the guitar at all. It's really odd. I'm kind of at a loss. I'm fairly certain the opto is in correctly. It had a white dot on one pin. I assumed that was the polerized side and it is in the positive lead pad. Could the opto be causing me to get no signal at all though the buffer though?
On the NSL32 the dot is negative.
Can you confirm that you have signal at the opamp's + input but not at the output? The buffer contains several parts so I just want to narrow it down. Also, what voltage do you have on the TL072 pin 8?
The dot is Negative?! What kind of jerk does that?! There's a dark corner of hell for people like that guy.
I just reordered another board. A buddy wants one too! ha! I'll swap the octo-coupler around and see what kind of results i get then if that doesn't take care of it i'll post you the voltages. Thanks for the replies man! top notch boards by the way! I'm really impressed with the construction. Very classy.
Hi Taylor -
I ordered the board and chip back in May, worked on it off & on in the fall, and finally finished it. I was worried after reading this thread, but it worked right away with no ticking!! Great sounding pedal! I took many ideas from the thread, including using rotary switches for the multiply and waveform knobs. Thanks for a great board & chip, I'm thinking of building another for a friend of mine.
Bob C
Glad you enjoyed it Bob. I pass the thanks on to Tom, Mike, Chris, and the others that made this project what it is. :)
Here's a picture. It has a light metalflake which makes the picture look splotchy. It's actually pretty subtle.
(http://i1254.photobucket.com/albums/hh606/bcalla44/TapTempoTremExt_zps99e23e60.jpg)
Quote from: bcalla on December 26, 2012, 04:54:47 PM
Here's a picture. It has a light metalflake which makes the picture look splotchy. It's actually pretty subtle.
That's gorgeous! I need to figure out how to do the graphics...
Quote from: bcalla on December 26, 2012, 04:54:47 PM
Here's a picture. It has a light metalflake which makes the picture look splotchy. It's actually pretty subtle.
(http://i1254.photobucket.com/albums/hh606/bcalla44/TapTempoTremExt_zps99e23e60.jpg)
Hey, Gorgeous! Tripping on that one! Nice work!
T.
I just finished mine. great build! lots of fun! I can't seem to dial out the ticking on the half note and quarter note multipliers though. higher values on the multiplier are fine. swapped the opto once already. no change. using an NSL-32. any thoughts?
ps. these PBS's are SO nice! I purchased this one with an echo base PCB about 6 months ago. BEAUTIFUL boards! Best quality I have seen.
Quote from: GuitarTek86 on January 19, 2013, 02:58:01 AM
I just finished mine. great build! lots of fun! I can't seem to dial out the ticking on the half note and quarter note multipliers though. higher values on the multiplier are fine. swapped the opto once already. no change. using an NSL-32.
I've got the same problem. I tried 3 NSL-32's and a couple of other VTL's...
And I tried to tap the tempo for some weeks now, but I don't get it. It's always much too fast. Maybe the software debouncing isn't enough for some switches (It's a Carling "normally open" type)? Would adding a debouncing circuit around a 74hc14 help?
IME a little finesse is required in tapping right. Taps need to be longer presses.
As far as ticking, I would go back to the first pages of the thread and see if any of the solutions there help.
I didn't have to ELIMINATE ticking, but I did factor it in to my layout. One of the posts mentioned that keeping the LED leads as short as possible so I positioned the board so that the LED solder pads were directly ove the LED hole. To do that I used a PC mount pot only for the tempo twisted/rotated the pot placement to figure out where I needed to place the LED. There is a gut shot below showing what I mean. If you're wondering, the trimpot on the stompswitch is to match the brightness of the bypass LED with the tempo LED.
(http://i1254.photobucket.com/albums/hh606/bcalla44/TapTempoTremInt_zps2db102bb.jpg)
I just finished building this up and I'm just working out the ticking (haven't boxed it up yet). Similar to a what was posted in the first few pages of the thread, the only way I've been able to eliminate the ticking so far is to leave the LED at maximum brightness with the trimpot set at no resistance. Once I have the LED at full brightness, I can set the NSL-32 trimmer at any value and ticking is very minimal if any at all.
So the question I have, since I didn't see it mentioned, does leaving the LED so bright have any negative impact on anything?
Thanks,
J
Can damage your vision (really - blue light is especially bad IIRC), draws more power, maybe shorter LED life, but other than that I can see no significant drawbacks.
Cool, I'll start wearing shades when I play, a win-win! Or maybe I'll try to diffuse the led. Thanks Taylor
Any ETA on new stock of these boards?
Anxious to get one....
-STP
Quote from: stone temple pinot on February 09, 2013, 11:15:38 AM
Any ETA on new stock of these boards?
Anxious to get one....
-STP
This.....................
Gonna be a while unfortunately. A few weeks to a month.
Cool....let us know.
Ok haven't posted for a while. Been super busy and have bad no time to work on pedals. But the other day I thought I'd try and work on this pedal again only to find I have a even bigger problem. My previous problem is that I could not get the ticking to stop. I even got a new Opto. After going up for a while I decided to try working on it again. Not it doesn't work at all! No sound at all comes through. Completely silent.....any suggestions as to what happened? It's just been sitting. I'm really sad cause this was my fav pedal when I got it working once then I unplugged it and plugged it back in and I've had nothing but problems :(
No sound could be anything. As usual, check here:
http://www.diystompboxes.com/wiki/index.php?title=Debugging
wondering if anyone has had a chance to measure current draw?
Just thought I'd ask if boards/ic were available now?
thanks :icon_cool:
They're on the way from the fabricators. Hoping to get them this week.
Please sign me up when they o arrive ! Thank you !! :icon_lol:
I'm guessing the website wont allow orders til you have stock?
Quote from: pastiche on April 11, 2013, 08:21:42 AM
I'm guessing the website wont allow orders til you have stock?
Right, I take down the purchase button while it's out of stock. I'm not set up to do pre-orders and keep track of them easily unfortunately.
I definitely want one. Components ready and waiting.....
STP
The tap trem is back in stock now. :)
Quote from: Taylor on June 23, 2010, 04:05:04 PM
Here you go. I'll also add this to the PDF. Note that my way is a little different from joinpobob's suggestion. His leaves the PWM output of the TAPLFO floating when the circuit is bypassed, and while this seems to work for him, it's suppose to be bad practice to do this. In my diagram, I ground the PWM output in bypass through a 10k resistor instead of just disconnecting it.
(http://img820.imageshack.us/img820/6872/taptempotremalternateby.th.jpg) (http://img820.imageshack.us/i/taptempotremalternateby.jpg/)
I can't see the pic in this post. Is it the same as the wiring on the build doc?
Also...where are you guys getting 22k trimpots? 25k would be fine wouldn't they?
That link must have gone dead. Sorry. I'm not sure if I have the file anymore. Does anyone have it saved on their computer?
25k should be fine.
Quote from: Taylor on May 03, 2013, 09:18:44 AM
That link must have gone dead. Sorry. I'm not sure if I have the file anymore. Does anyone have it saved on their computer?
25k should be fine.
This?
(http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/taptempotremalternateby.jpg.html)
http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/taptempotremalternateby.jpg.html (http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/taptempotremalternateby.jpg.html)
Thanks Lurco.
Thanx guys! Can I still put a non-blinking bypass LED on the switch in tandum with this? Hey, BTW, I have another populated board that someone gave me but they trashed it. The chip is still good though. Could I just buy another board minus the chip?
Quote from: tenwatt on May 06, 2013, 10:17:03 AM
Thanx guys! Can I still put a non-blinking bypass LED on the switch in tandum with this? Hey, BTW, I have another populated board that someone gave me but they trashed it. The chip is still good though. Could I just buy another board minus the chip?
Anybody?
I can't think of an easy way to light another LED without a 4pdt switch.
Sure, you can buy just the board. Send me an email through the site and I'll set you up.
I'd really like to have a bypass LED that goes on/off with the footswitch and the tempo LED that is ALWAYS on AND, obviously, minimumize the ticking. Can I do that?
Are the PCB's shipping now?
Yes.
Quote from: tenwatt on May 09, 2013, 11:20:40 AM
I'd really like to have a bypass LED that goes on/off with the footswitch and the tempo LED that is ALWAYS on AND, obviously, minimumize the ticking. Can I do that?
Hook the rate LED to ground so it's always on then wire a normal on/off LED to the footswitch? I haven't read the project document for a year or so, but that seems like a normal thing to do.
But that's not compatible with the alternate bypass, which grounds the PWM signal when in bypass.
Doesn't this guy have a bypass and tempo LED? Does this not work?
Quote from: bcalla on December 26, 2012, 04:54:47 PM
Here's a picture. It has a light metalflake which makes the picture look splotchy. It's actually pretty subtle.
(http://i1254.photobucket.com/albums/hh606/bcalla44/TapTempoTremExt_zps99e23e60.jpg)
He must not be using the alternate bypass. It's not possible to have a flashing LED in bypass with the alternate bypass because it grounds the PWM signal so there's no varying voltage going to the optocoupler.
Have you actually built the pedal and had ticking issues, or are you planning this in advance? The alternate bypass is not necessary for most people.
Quote from: Taylor on May 17, 2013, 04:17:46 PM
He must not be using the alternate bypass. It's not possible to have a flashing LED in bypass with the alternate bypass because it grounds the PWM signal so there's no varying voltage going to the optocoupler.
Have you actually built the pedal and had ticking issues, or are you planning this in advance? The alternate bypass is not necessary for most people.
Planning in advace. If it's not necessary for most I will try it without.
I have been unhappy with the absence of a pcb layout for a home-brewed Tap Tremolo for quite a while. So I decided to dive into pcb layouting with the very nice schematic by the electric druid (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf) and came up with working solution (http://forum.musikding.de/vb/attachment.php?attachmentid=11757&d=1365895082).
My colleague Bastelfix in turn was unhappy with the size of the board and did a very good job (indeed, I'm impressed) in reducing the size and was even able to implement a hum-filter on the board.
So, for all the friends of etching, here's the final, single sided solution of the here discussed circuit:
http://forum.musikding.de/vb/attachment.php?attachmentid=11901&d=1368734215
http://forum.musikding.de/vb/attachment.php?attachmentid=11900&d=1368734198
You'll find the whole threat in the german Musikding forum: http://forum.musikding.de/vb/showthread.php?32683-Tap-Tempo-f%FCr-quot-Das-Tremolo-quot&p=346218#post346218
Best, Lars
Quote from: lars-musik on May 21, 2013, 05:03:22 PM
I have been unhappy with the absence of a pcb layout for a home-brewed Tap Tremolo for quite a while. So I decided to dive into pcb layouting with the very nice schematic by the electric druid (http://www.electricdruid.net/datasheets/TAPLFO2Datasheet.pdf) and came up with working solution (http://forum.musikding.de/vb/attachment.php?attachmentid=11757&d=1365895082).
My colleague Bastelfix in turn was unhappy with the size of the board and did a very good job (indeed, I'm impressed) in reducing the size and was even able to imply a hum-filter on the board.
So, for all the friends of etching, here's the final, single sided solution of the here discussed circuit:
http://forum.musikding.de/vb/attachment.php?attachmentid=11901&d=1368734215
http://forum.musikding.de/vb/attachment.php?attachmentid=11900&d=1368734198
You'll find the whole threat in the german Musikding forum: http://forum.musikding.de/vb/showthread.php?32683-Tap-Tempo-f%FCr-quot-Das-Tremolo-quot&p=346218#post346218
Best, Lars
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Ah yes. Just register - its a forum for diy stompboxes. Nothing filthy about it. I'm pretty sure it's worth it.
However, here's my first (and large) try on the subject. Good for those with fat fingers and clumsy soldering irons.
(http://www.freeimagehosting.net/rm912)
http://www.freeimagehosting.net/rm912 (http://www.freeimagehosting.net/rm912)
People with smaller fingers should try to register at the musikding forum in passing to gain access to the pdfs of Bastelfix.
Hey there!
I've tried googling and that has not helped. How well does the VTL5C3 work? I've seen some comments on it but not any conformation on it. It's on the data sheet for the taplfo chip so I assume it works well....
I am currently using NSL-32 and there is some ticking. I'm going to change the transistor tomorrow and see if that does anything. The trim pots don't help much so I'm pretty sure its the vactrol. The VTL5C3 is the only other one I have around hence the question.
Thanks!
The relevant parameters are the turn-on and turn off time. If you check the Perkin Elmer datasheet you can find the speed as compared to the NSL-32, but IIRC the 5c3 is kind of fast so might tick more. But worth a try since the tolerance on these things is so wide.
I've tried the VTL5C3 and still ticking ??? I have the optocoupler section socketed b/c I thought I may have this problem. I placed a 220k resistor where the LDR half would sit so see if it was something else and there is still ticking. If my thinking is correct there should be no ticking with just a resistors there since the ticking is cased from the on/offf time of the LDR. Right?
Also the ticking occurs when the pedal is bypass.
Have you read this thread and tried te fixes herein? Changed the 330p cap? Done the alternate bypass? I know it's a lot to read but the answers are all here.
Sorry I should have looked though this thread better :icon_redface:
Next question... I tried serching for this one but the terms I'm using may be a little generic terms for using the search function :icon_redface:
Anyway... Everything works great but there is some ticking when on the square wave and the sawtooths. It that normal since that the wave has a dramatic change when it switches off?
Thanks!
It's normal in the sense that it happens to a lot of people who build tremolos in general. If the trimpots haven't allowed you to trim out the ticking, try upping the 330p cap to a 1n-10n. Also make sure your wires, if any, are as short as possible and don't cross over each other unnecessarily. Sloppy wiring is often the biggest culprit.
I've changed it to 1n I'm going to put a socket there and see what works best. Thanks again!
Quote from: Taylor on June 11, 2013, 03:57:52 PM
It's normal in the sense that it happens to a lot of people who build tremolos in general. If the trimpots haven't allowed you to trim out the ticking, try upping the 330p cap to a 1n-10n. Also make sure your wires, if any, are as short as possible and don't cross over each other unnecessarily. Sloppy wiring is often the biggest culprit.
Which wires exactly might cause these problems?
If your audio in and out cross over the board, for example, they can pick up the digital signal capacitively.
while waiting on new optocouplers to hopefully remove ticking, i tried lower-current LEDs per .Mike's suggestion (page 20 I think) and that significantly reduced the tick
I can even get "tick free" operation with the Output LED trimpot set "all the way up" - but aren't I without current-limiting protection for the LED at that setting? It is a nice, very tolerable, brightness.
Secondly I've read elsewhere about using lower current op-amps to reduce ticking. Has anyone tried swapping a tl-022 for the tl-072, for example? I saw someone using one much earlier in the thread, but then he went silent . . .
I thought maybe my Volume knob wires were a culprit, but they made little difference in the ticking when moved around or even held straight above the board.
what did make a difference was when I moved the LED wires away from the power filtering. I've since shielded them, and all inputs/outputs. If I ever build another one I'll use the board mounted pots/LED configuration per the designer's intent.
Thanks for all the information in this thread!
The trimpot probably doesn't get 100% to the end of its travel, so you likely have some series resistance still.
No personal experience with other opamps so I'll leave that for others.
Is there any way to make the LED's brighter? What is the CLR in the circuit? I'm assuming one of the 22k trimpots? If so which one acts as the CLR for the LED?
I'm working on setting up the expression pedal to switch between the potentiometer and the onboard circuit contacts for controlling either the depth or the rate. The Catalinabread Semaphore has a toggle switch inside the pedal that switches the expression input between those two, so I know it's possible.
It occurs to me they may be using relay switching which is somewhat beyond my ken, at this moment. I've tried drafting up a couple of different ways to do it with mechanical switching, that I think would work, using 2 4PDT switches. the only problem being that I'm not sure it will work (still trying to finish figuring out the wiring,) and that having to use 2 switches is a royal pain/undesirable.
Has anyone else gotten this figured out, or know a better way to do it?
I can post diagrams tomorrow, to show more info. the gist of it is I drafted wiring the the grounds of all the jacks/pots/board contacts wired together, since ground is shared, and the 4 contacts on the switching jack connected to the middle rail of a 4pdt, and corresponding the tip and ring of the Depth pot and Depth board contacts on one throw, and the tip and ring of the Rate pot/board contacts on the other throw.
The issue with that being that while I can thusly switch the expression input between Depth and Rate, whichever one isn't selected on the 4PDT is disconnected from any potentiomer.
So I put another 4PDT to connect the potentiometers for rate and depth EITHER to the 4PDT that controls which parameter the expression input jack controls, or straight to the PCB pads. meaning if I select the expression input to control the Rate, I then can connect the Depth potentiometer directly to the Depth PCB connections.
tl;dr anyone have a tip on switching expression input control between two parameters?
Bump* I am using kingbright ultra bright white 5MM LED's and they are barely noticeable on the light plate. Any chance to change the input voltage on it? I tried hooking it up to its own power but lost signal from the circuit. Ideas?
I figured out how to switch the expression input between two of the pots (Depth, and Rate,) using a 6PDT Slide switch: Mouser part# 612-EG6201.
Here's the diagram for connecting it. http://imgur.com/MESslCq (http://imgur.com/MESslCq)
Does anyone have the voltages at which the multiplier switches? I built one with a 1P6T switch and my 1/16th notes don't work. The voltage I read at the multiplier's wiper was 4,72V. As it said in the pdf by ElectricDruid, anything over 3,75V goes to the default setting of x1.
I used his trick with two 5K1 and five 10K resistors in conjunction with the 1P6T, but I guess I need to tweak these values as it does not work perfectly. I would really appreciate it if someone has the (approximate) voltages, so I can test resistor values to get me there. Hopefully changing the 3K6 will be sufficient instead of changing the 5K1/10K combo.
Ok nevermind, I had another look at the schematic and enlarging the 3K6 should do the trick.
What is happening here? I jumpered the 1n4001 like Taylor suggested since the posts won't fit. I checked the polarity but when I plugged it in the 10 ohm resistor next to the 1n4001 started glowing and smoking. I quickly unplugged it and desoldered the effected resistors. HELP. This build has been kicking my butt for some reason. https://www.facebook.com/photo.php?fbid=691606790855393&set=pcb.691606900855382&type=1&theater (https://www.facebook.com/photo.php?fbid=691606790855393&set=pcb.691606900855382&type=1&theater) https://www.facebook.com/photo.php?fbid=691606837522055&set=pcb.691606900855382&type=1&theater (https://www.facebook.com/photo.php?fbid=691606837522055&set=pcb.691606900855382&type=1&theater)
I don't have access to the MusicPCB email at home, so I can't check - did I really tell you to replace the diode with a jumper? If so, I apologize; I must have been half-asleep because that is very dumb advice, because it'll do exactly what you saw. If I did tell you that, email me so I can fix this for you.
You don't need the diode for the pedal to work. It's for reverse polarity protection so if you plug in th wrong power supply you won't burn anything up. For now, if you can't fit it, and you can't surface mount it to the pads, then leave it off the board.
Replace the resistors and fire it up and see if it works.
Taylor - Wondering if you might help me with getting the flashing LED brighter? I have tried different trimmers, tried maxing out the trimmer to see how bright the LED can get and still not getting a very bright LED. Only reason I need it so bright is so that I can see it in the Light Plate being used. I did sub a 2n3906 for the 2n3904 as I don't have one on hand. The pedal works perfectly just wondering if there's a way to get the LED brighter. Also I took the LED off the 3pdt and put it on the board directly.
Taylor, I re-read the email. I misread your instructions to surfacemount the diode and thought you meant to leave the diode off and surfacemount the two pads... not leave it off all together OR surfacemount the diode. My confusion. I will replace the resistors and try it again without the diode.
FIXED! I guess I just need to read me emails without thinking I know what needs connection :icon_redface: Thanks Taylor. Ticking has been dialed out. Now to rewire the depth knob so clockwise is deeper.
Quote from: aryk on August 04, 2013, 01:46:37 PM
Taylor - Wondering if you might help me with getting the flashing LED brighter? I have tried different trimmers, tried maxing out the trimmer to see how bright the LED can get and still not getting a very bright LED. Only reason I need it so bright is so that I can see it in the Light Plate being used. I did sub a 2n3906 for the 2n3904 as I don't have one on hand. The pedal works perfectly just wondering if there's a way to get the LED brighter. Also I took the LED off the 3pdt and put it on the board directly.
You subbed a PNP transistor for an NPN. I don't really understand how it's working, but that would be my first thing to change to try to get the LED blinking brighter if it's dim.
I wondered that myself. Apparently the 2N3906 is able to perform in place of a 2n3904 (according to the data sheet). That odd anomaly aside, I swapped it out for the 2N3904 and nothing changed with the LED.
Hmm, interesting.
The LED brightness is controlled by the trimpot next to the TL072. If you're using a bright LED and you've got that trimpot dimed then you must have some problem with your trimpot soldering I guess. Have you thought about just using a much brighter LED (they make retina burning ones for crazy people).
Hi, I've just finished building the taptempo but alas when I plug it in no signal from my guitar gets through :icon_sad:. Instead it generates popping noises and weird sounds, you can control the tempo waveform depth etc. Of these sounds using the corresponding pot and the LED flashes along with the rhythm. So I'm thinking something is working here. The bypass also works and allows clean signal from my guitar through. The trim pots are all set to halfway and if these are adjusted it changes the effect. Interesting sounds but sadly not the ones I was after! Could someone please help!! I've made a few pedals before, but for all intensive purposes treat me as if i'm stupid. It's probably something blindingly obvious.
Here are the voltages I've measured at the main components
TAPLFO
1 = 5.04 14 = 0.03
2 = 0.87 13 = 4.32
3 = 2.30 12 =3.09
4 = 4.99 11 = 0.48
5 = varies from 1.8 to 3.3 10= 5.03
6 = 0.02 9 = 3.81
7 = varies from 1.4 to 3.6 8= 4.99
TL072
1 = 4.45 8 = 8.90
2 = 4.45 7 = 4.44
3 = 4.22 6 = 4.44
4 = 0 8 = 4.22
2N3904
Leg nearest TAPLFO = varies from 1 to 2.5
Middle leg = from 0.3 to 0.5
Nearest TL072 = 0
Voltage reg
Top leg (nearest wave distort, oh I have the wave distort control in place BTW) = 5.03
Middle = 0
Bottom (nearest 330nf) = 8.8
Opto
+ve = 2.5 to 3.5
-ve = 1.8 to 3.2
Both other legs = 4.41
And on the diode voltage varies on top(banded) leg (anywhere between 8 and 0) and no voltage on the bottom leg. Also for the electrolytic caps +ve leg reads voltage (4.4 for the 10uf and 8.8 for the 100uf and –ve leg for both =0.
Thanks
whats happened to musicpcb.com?
the page doesnt load and a virus warning pops up
Quote from: bcalla on December 26, 2012, 04:54:47 PM
Here's a picture. It has a light metalflake which makes the picture look splotchy. It's actually pretty subtle.
(http://i1254.photobucket.com/albums/hh606/bcalla44/TapTempoTremExt_zps99e23e60.jpg)
Hey.. I'm about to builds a tap tremolo using this chip (http://www.uk-electronic.de/Download/Manual%20Tap%20Tremolo.pdf (http://www.uk-electronic.de/Download/Manual%20Tap%20Tremolo.pdf)) and I want to print up a label for the box. My question is whether the multiplyer and waveform positions are always the same, such as where you've indicated them on your knobs here?
thanks
Quote from: 9aul on August 07, 2013, 05:35:13 AM
Hi, I've just finished building the taptempo but alas when I plug it in no signal from my guitar gets through :icon_sad:. Instead it generates popping noises and weird sounds, you can control the tempo waveform depth etc. Of these sounds using the corresponding pot and the LED flashes along with the rhythm. So I'm thinking something is working here. The bypass also works and allows clean signal from my guitar through. The trim pots are all set to halfway and if these are adjusted it changes the effect. Interesting sounds but sadly not the ones I was after! Could someone please help!! I've made a few pedals before, but for all intensive purposes treat me as if i'm stupid. It's probably something blindingly obvious.
Here are the voltages I've measured at the main components
TAPLFO
1 = 5.04 14 = 0.03
2 = 0.87 13 = 4.32
3 = 2.30 12 =3.09
4 = 4.99 11 = 0.48
5 = varies from 1.8 to 3.3 10= 5.03
6 = 0.02 9 = 3.81
7 = varies from 1.4 to 3.6 8= 4.99
TL072
1 = 4.45 8 = 8.90
2 = 4.45 7 = 4.44
3 = 4.22 6 = 4.44
4 = 0 8 = 4.22
2N3904
Leg nearest TAPLFO = varies from 1 to 2.5
Middle leg = from 0.3 to 0.5
Nearest TL072 = 0
Voltage reg
Top leg (nearest wave distort, oh I have the wave distort control in place BTW) = 5.03
Middle = 0
Bottom (nearest 330nf) = 8.8
Opto
+ve = 2.5 to 3.5
-ve = 1.8 to 3.2
Both other legs = 4.41
And on the diode voltage varies on top(banded) leg (anywhere between 8 and 0) and no voltage on the bottom leg. Also for the electrolytic caps +ve leg reads voltage (4.4 for the 10uf and 8.8 for the 100uf and –ve leg for both =0.
Thanks
Build an audio probe and probe through the opamp half of the circuit. Your digital side is working, so you just need to find the point where your audio stops. Doublecheck the datasheet for your opto to be sure you have it in the right way.
Quote from: smacca on August 07, 2013, 09:10:06 AM
whats happened to musicpcb.com?
the page doesnt load and a virus warning pops up
Well, it's loading for me, however recently the site keeps getting hacked so some browsers might flag it as malware and block it. I don't know what to do about this other than get a new site... If any web gurus want to PM me with their thoughts I'd be very grateful.
here is what pops up when i go to the site:
(http://i248.photobucket.com/albums/gg179/jahmeck/musicpcbvirussmall.jpg) (http://s248.photobucket.com/user/jahmeck/media/musicpcbvirussmall.jpg.html)
it has only been doing this since i mentioned it earlier, maybe 2 weeks. before that it worked fine for me.
.... and im ready to buy this board ???
Are the trimmer values 22K or 10K?
Brane
22k will give more range in dialing it in, so I recommend that.
Thanks :)
Is the depth pot supposed to be wired/soldered so that it would be under the board (inline with the multiply pot)? Or sticking out the side, similar to the tempo, waveform and multiply pots?
All the images are gone out of this thread for the most part....so I can't find a reference.
Thanks
STP
Hi,
I haven't touched the trimpot, because my pedal works.. but the tremolo is louder than the bypassed mode.. does the trimpot change this?
Thanks
Yes, the trimpot above the tl072 is the gain.
Taylor, do you have any idea what could cause the depth pot not to fully work? When setting this one to max, the trem should be dead quiet during the dark phase. However, mine will not go completely quiet. I've been looking at different things, measuring, even replacing the NSL32. All to no avail. Other than this, it works like a charm.
Setting the trims correctly should get a good light/dark difference. Measure to make sure your depth pot is ranging 0v-5v, but I suspect your problem is in the trims.
I've measured the pot again and it goes from 0V to 4,94V. Could this 0,06V difference be the culprit? I doubt it as the pedal stays quite loud even at full depth.
I have been tweaking the trimmers a lot and I've made this pedal before so tweaking them should not be such an issue.
Aaaaaaaaaaaaaaaaand it works. It always did. My testing rig has a sine generator and a ruby amp. Somehow the sine bleeds through to the Ruby ...
How feasible would it be to add 3 numeric LEDs that put out the LFO speed in BPM? Would it be too difficult and/or crazy? :icon_smile:
How feasible? The taplfo chip has a clock out signal on pin 7 that pulses at the same rate as the LFO, hook that up to a microcontroller, program it to read the pulses and convert the speed into BPM and display it on some LED displays, very easy or very hard depending on if you have any skills in that area.
I'd be very surprised if there wasn't an Arduino based project out there that does this so you could do things like tap or play in a beat and it would tell you the BPM, maybe a metronome or something.
Thanks for the reply slacker. I guess that's beyond what I'm capable of. I have no idea on how to program a microcontroller or how to convert the speed into BPM, but you pointed me in a direction. I'll do some research online. Thanks!
Hi, I just want to add mine experience with building this pedal.
-First thing I didn't do is build it with waveform pot and that was mistake because I couldn't stop thinking about that option :D , so at the end I did add that pot and it gives you really more versatility.
-Second thing is about NSL-32, I have tried 4 of them and they all had problems with ticking and that drive crazy 'cause I could rid of it, so I grab those GL5516 ldr's that I got from ebay and wrap mine own optocop. with white led and I got best results with them and no ticking..
-Third thing is that with those GL5516 I have noticed that you have more output if this is something interested to someone.
-Fourth thing is about that 330pF cap, raising value of this cap really helps with ticking and adding buffer in front of the pedal can remove ticking in bypass (at least in mine build)
-Finally This Tremolo is not ticking in the FX loop of the amp even when used with those NSL-32
Quote from: Taylor on August 07, 2013, 06:24:28 PM
Quote from: 9aul on August 07, 2013, 05:35:13 AM
Hi, I've just finished building the taptempo but alas when I plug it in no signal from my guitar gets through :icon_sad:. Instead it generates popping noises and weird sounds, you can control the tempo waveform depth etc. Of these sounds using the corresponding pot and the LED flashes along with the rhythm. So I'm thinking something is working here. The bypass also works and allows clean signal from my guitar through. The trim pots are all set to halfway and if these are adjusted it changes the effect. Interesting sounds but sadly not the ones I was after! Could someone please help!! I've made a few pedals before, but for all intensive purposes treat me as if i'm stupid. It's probably something blindingly obvious.
Here are the voltages I've measured at the main components
TAPLFO
1 = 5.04 14 = 0.03
2 = 0.87 13 = 4.32
3 = 2.30 12 =3.09
4 = 4.99 11 = 0.48
5 = varies from 1.8 to 3.3 10= 5.03
6 = 0.02 9 = 3.81
7 = varies from 1.4 to 3.6 8= 4.99
TL072
1 = 4.45 8 = 8.90
2 = 4.45 7 = 4.44
3 = 4.22 6 = 4.44
4 = 0 8 = 4.22
2N3904
Leg nearest TAPLFO = varies from 1 to 2.5
Middle leg = from 0.3 to 0.5
Nearest TL072 = 0
Voltage reg
Top leg (nearest wave distort, oh I have the wave distort control in place BTW) = 5.03
Middle = 0
Bottom (nearest 330nf) = 8.8
Opto
+ve = 2.5 to 3.5
-ve = 1.8 to 3.2
Both other legs = 4.41
And on the diode voltage varies on top(banded) leg (anywhere between 8 and 0) and no voltage on the bottom leg. Also for the electrolytic caps +ve leg reads voltage (4.4 for the 10uf and 8.8 for the 100uf and –ve leg for both =0.
Thanks
Build an audio probe and probe through the opamp half of the circuit. Your digital side is working, so you just need to find the point where your audio stops. Doublecheck the datasheet for your opto to be sure you have it in the right way.
Quote from: smacca on August 07, 2013, 09:10:06 AM
whats happened to musicpcb.com?
the page doesnt load and a virus warning pops up
Well, it's loading for me, however recently the site keeps getting hacked so some browsers might flag it as malware and block it. I don't know what to do about this other than get a new site... If any web gurus want to PM me with their thoughts I'd be very grateful.
Hi,
Annoyingly I have been busy with other less interesting things, so have only just got round to building my audio probe and checking the circuit. I didn't get too far before the audio signal ended and was replaced by a loud pulsing sound (I can control the pulsing with the pots). This pulsing sound also comes through when the effect is switched to bypass and my probe isnt touching anything (its just earthed on the negative). However if i turn the effect on this pulsing disappears when I am not using the probe. Anyway the signal gets thru if i probe the in-put (good start!) it then gets past the 1u cap ( i should note that the 0V side of the 1M resister makes the pulsing sound). when it gets to the op amp (TL072CN) only really pin 1 gets a clean signal, the rest have a very loud pulsing sound and its hard to hear over that if there's any signal behind that. Pretty much the rest of the circuit is like that. I'm pretty sure I have the opto the right way round, i have an NSL7053 (with 32 written on the top) the flexible wires are at the resister end and the side where the dot is goes to the -ve. Ive replaced the op amp (another TL072CN) to check if that's faulty but it's just the same.
Any ideas would be very much appreciated.
Thanks.
Hey there
I'm having problems too.
I've just hooked the circuit up to my test rig and there's a problem. When engaged there's no sound. The tempo indicator LED is working as it should and the knobs effect how fast/deep the LED lights up but there' just no sound. I have sound in bypass.
I've checked for solder bridges and that my components are correct but everything seems fine. It just seems strange that the effect looks to be working but somehow the signal isn't coming out at the other end.
Here are some photos. Can anyone see anything obvious that I've missed?
(http://i.imgur.com/ez3DtE5.jpg)
(http://i.imgur.com/DLSd6hg.jpg)
For reference (ignore the red circles)
(http://i.imgur.com/HT6wREo.jpg)
Thanks in advance
Hey guys I need some assistance. Its been a while since I've been on or working on pedals, I got busy graduating. But this was the last pedal I had made nd I could never get it to work right. Then last time I was trying to fix the ticking, it just quit working all together. Now no sound comes through at all. I took the switch out of the circuit so that that wouldn't be part of the issue. When I plug in the power the light barely comes on, so I'm wondering if the board is not getting enough power. What are your suggestions for trying to figure this out?
^ Use the schematic to trace down the voltage paths and use your multimeter to make sure all parts are getting the voltages that they need.
Quote from: mth5044 on October 25, 2013, 03:18:25 PM
^ Use the schematic to trace down the voltage paths and use your multimeter to make sure all parts are getting the voltages that they need.
What are the voltages everything should be?
Quote from: threepwood on October 24, 2013, 10:47:50 PM
Hey there
I'm having problems too.
I've just hooked the circuit up to my test rig and there's a problem. When engaged there's no sound. The tempo indicator LED is working as it should and the knobs effect how fast/deep the LED lights up but there' just no sound. I have sound in bypass.
I've checked for solder bridges and that my components are correct but everything seems fine. It just seems strange that the effect looks to be working but somehow the signal isn't coming out at the other end.
Here are some photos. Can anyone see anything obvious that I've missed?
(http://i.imgur.com/ez3DtE5.jpg)
(http://i.imgur.com/DLSd6hg.jpg)
For reference (ignore the red circles)
(http://i.imgur.com/HT6wREo.jpg)
Thanks in advance
The glaringly obvious lack of trimpot?!
I think he's doing the same mod I did - replacing the trimpot with an external pot. The wires are on the bottom.
Maybe not worth mentioning, however I coincidentally had the very same problem with a Tremulus Lune. I spent days debugging until I discovered, the PSU was not working properly anymore. Have you tried a different one or a battery? If it worked before, albeit with a ticking LFO, there's a possibility that's it.
Yep, I've wired the gain trimmer as an external pot as suggested in the build doc.
Thanks for the PSU suggestion. I tried a different one and still no luck. I think it may be a grounding issue but I can't find where it is. So frustrating!
Build and use an audio probe...
hi there, long time reader first time poster.
i built the tap tempo tremolo and i had issues with ticking, tried adjusting the 330p cap to 10n and all other suggestions, still ticking.
at some point i realised it was my amplifier that produced (most) of the ticking. if i put the tremolo into another amp it was quiet. (at very loud volumes you can hear a subtle click)
so to anyone struggling with clicks and ticking, try another amplifier, it might solve your problem.
so i now have a fully working tremolo, with clock output and metronome in!!! great. taylor thanks so much for a great pcb!
cheers
Quote from: lokki on November 20, 2013, 11:25:30 AM
hi there, long time reader first time poster.
i built the tap tempo tremolo and i had issues with ticking, tried adjusting the 330p cap to 10n and all other suggestions, still ticking.
at some point i realised it was my amplifier that produced (most) of the ticking. if i put the tremolo into another amp it was quiet. (at very loud volumes you can hear a subtle click)
so to anyone struggling with clicks and ticking, try another amplifier, it might solve your problem.
so i now have a fully working tremolo, with clock output and metronome in!!! great. taylor thanks so much for a great pcb!
cheers
I had never noticed a click with my tube amp, but heard one when I tried it on my 1W punch SS amp.. which amps did you try it on?
i actually tried it with bass on a gallien krueger combo amp. the normal input did click, the return of the amp did not click. i then tried a fender twin, no click either...
i realised that the click on the gk amp is only when the led goes off, not when it goes on...
Hi, I've been trying to get this pedal working for some time, and having got my echo base recently working (which by the way is absolutely amazing, I think I'll be singing its praise and posting some pics soon) I've been filled with a new found drive to get my tap tempo up and running. So my problem was ticking (I seem to be in a similar boat as many other people, so sorry if you've heard it all before). When I say ticking, its not really a ticking but a variety of noises as the LED switches on and off which changes with the rate and wave shape etc. this is much louder than the actual guitar signal (which if you listen carefully you can hear and sounds quite nice).
ANYWAY, i have played around with the trim pots to no avail, ticking is always louder than guitar signal. I then replaced the 330p with a higher value cap as suggested, I've gone up to 22n (which is probably overkill but I just wana get this ticking out my head). this didnt change a thing. I've also replaced the opto (maybe a slight reduction but it was still louder than the guitar). These are the values I had for the chips:
(http://farm3.staticflickr.com/2841/12361645445_55f9aca1c3_n.jpg)
I know this post is already dragging on, but sorry I'm not going to stop there. :icon_rolleyes:
So I went back to this pedal with my 3rd NSL-32 and replaced it. While I was at it I thought id re wire the jack and power so they switch the power on/off (like so http://www.beavisaudio.com/techpages/PedalPower/ ) , I also just used the ground tab for grounding the in jack (which is also linked the the ground of the out jack) since I had been using the LED -ve as a ground when fault finding which I've since read is a no no, especially for ticking. anyway I plugged in to test and now I get distortion! like a fuzz pedal.. the trem is working behind this and ticking is less (perhaps something I can even tame) but first I'd like to address the fuzz issue. Ive read this is probably something about bias but I'm not quite sure how to tackle it. Any suggestions would be much appreciated. Here are the new values since adding the new NSL and change of wiring:
(http://farm4.staticflickr.com/3746/12361644965_f9f7f791fd_n.jpg)
Thanks to anyone can be bothered to read this essay, and a bigger thanks to any suggestions.
Also I cant seem to find the pic of the new bypass wiring that Taylor suggested and others have referred to
Quote from: Taylor on August 17, 2010, 05:00:59 PM
The LED does flash with the tempo already.
The bypass wiring in the PDF has kind of been replaced by the diagram in this thread:
http://www.diystompboxes.com/smfforum/index.php?topic=84020.msg713301#msg713301
Do you need some special glasses to see this or has it disappeared?
And could this be the answer to all my ticking worries?
For me, debugging with an audio probe has always been easier than looking at DC voltages. The audio path of this circuit is very simple, so you should be able to trace from input to output to see where things go awry. Since your LED is flashing and presumably responding to the pots, most of the circuit is working properly.
Since you're now getting distortion, this could be because you have the gain trim for the last opamp cranked up very high, so I'd revisit the trimpots now that you have audio.
The picture that you're not seeing doesn't change anything when the pedal is on. It grounds the LFO signal when in bypass. Ideally I should find that picture or reproduce it and add it to the documentation on the site. The day job is taking up all of my time right now but I will try to get to it! Feel free to bug me via email if I haven't gotten around to it in a week or two. :)
Thanks Taylor. I'll check tonight but I don't think I was getting any ticking In bypass, so I guess Id probably be OK with the standard switch wiring.
Last time I checked with an audio probe, I was getting ticking throughout the whole circuit accept right at the beginning (it gets past the 1u cap and then when it gets to the op amp only really pin 1 gets a clean signal, the rest have a very loud pulsing sound. The 0V side of R10 also made the pulsing sound.) This was last time I checked and I haven't checked since changing the opto and getting distortion. I'll get onto that and see what I can find. It may help with pinning down this distortion ,as I fiddled around with the gain trim and just got a quieter distorted signal and didn't get rid of the fuzz, it may be something else that i could find with a probe.
Just wanted to say that I finally boxed my Tap Tempo Tremolo board up (after ordering it years ago!) and it's awesome. I now have at least 2 friends who want one as well...Great boards, as always!
Just found where the fuzz was coming from! (I've only just got round to actually looking at it). Couldn't work out where it was with the audio probe but then as I was going through I noticed one of the opto legs was touching a leg of a trim pot. Sorted that out and that sorted the fuzz out. Now its working pretty good. Ticking is still there most of it can be removed using the trim pots (its not huge but still potentially a problem at higher volumes). Since I've already replaced the 330p with a 22n I think I'll go back and try the other two optos I have kicking about (I think I hastily changed these when the problem was else where). I think I'm well on the way to getting this one sorted. One problem I have noticed however it that with when I change the wave form pot there is a point where I just get LED flashing (a quite harsh on and off) but absolutely no signal (just ticking), is this just in between switching wave forms? either side of this point all is fine. This is something I can live with, but I was just wondering if this is normal or if I should consider replacing the pot or something like that.
Thanks for all the help so far.
My guess is that you have the wave distort all the way to one side so the square waveform has 1% duty cycle. Because of the slow speed of the opto it will never turn on this way. While getting used to the pedal try keeping wave distort in the middle until you understand its function.
Great, that's easy to solve! thanks for the info Taylor.
Hey there
After ballsing up my first attempt, I'm having another go at building this circuit.
I've decided to wire the internal volume trimmer as an external volume pot. Just wondering how to go about this. The build doc says to use a 25K A pot but doesn't say how to connect it. Do the trimmer's PCB pads correspond to a pots lugs as I've numbered below or have I mixed things up?
(http://i.imgur.com/11E47No.jpg)
Thanks in advance.
That will work but it might work backwards. I get confused with the 1 2 3 numbering as I've seen people use it differently (are we looking at the back of the pot when counting or the front? Lugs pointing up or down?).
On the bottom of the board you should see that two of the trimpot leads are connected in the PCB. These two should go to the middle and right lugs when the pot shaft is pointing towards you, lugs pointing towards your feet. You can even just wire from the center pad to the center lug and connect a short wire from right lug to center lug. The other connection goes to the left lug of the pot.
If that's still confusing, short answer is to try it like you wrote it. If backwards, swap wires.
Quote from: Taylor on March 04, 2014, 10:26:40 AM
That will work but it might work backwards. I get confused with the 1 2 3 numbering as I've seen people use it differently (are we looking at the back of the pot when counting or the front? Lugs pointing up or down?).
On the bottom of the board you should see that two of the trimpot leads are connected in the PCB. These two should go to the middle and right lugs when the pot shaft is pointing towards you, lugs pointing towards your feet. You can even just wire from the center pad to the center lug and connect a short wire from right lug to center lug. The other connection goes to the left lug of the pot.
If that's still confusing, short answer is to try it like you wrote it. If backwards, swap wires.
Thanks Taylor. That's great.
One more question.
I know the other two trimmers on the board can be 10k or 22k. Will 25k also work or is that too large? I only ask as I have a couple of 25k's spare and so won't have to order any in if they will do the trick.
Thanks again.
25k is fine. The "gain" trimpot is a variable resistor in the feedback loop of the last opamp stage. In this case, larger resistance equals more gain. So, with a bigger pot value you'll be able to boost the gain higher at maximum. Things will distort if you amplify too much of course.
Cheers Taylor
Finally got round to putting it together.
I wasn't getting any effected signal so poked around with my audio probe and found that the wet signal was present at pin 7 of the IC so I just soldered the out wire to the underside of the pin (spot the 1uf cap poking out of the right side of the board). No idea how it's working but remarkably it is. Although I do get some horrible clicking in certain settings. I tried upping the cap next to the LDR but no luck. In fact I took the cap out altogether at one point and there was no noticeable difference to when there was one in place. I might look to fix it in the future but I'm done with it for now. Can't wait to give it a run out! Hope you like it.
(http://img.tapatalk.com/d/14/03/12/zajatuja.jpg)
(http://img.tapatalk.com/d/14/03/12/jyhe9eha.jpg)
Cool design, looks really nice!
Finished this a couple weeks ago, thanks to all the help on this forum! I used rotary switches for the multiplier and waveform, and allowed for an external tap tempo. I found the finishing (decal, clear coat, etc) to be the most difficult and time consuming part of the process. Hopefully I'll get better at that part ;D
https://www.dropbox.com/s/cyxnatfm80vb54a/2014-03-30%2018.42.57.jpg (https://www.dropbox.com/s/cyxnatfm80vb54a/2014-03-30%2018.42.57.jpg)
https://www.dropbox.com/s/1salo0g5gm4rt2e/2014-03-30%2018.47.37.jpg (https://www.dropbox.com/s/1salo0g5gm4rt2e/2014-03-30%2018.47.37.jpg)
Had to use links; inserting a picture from my dropbox didn't seem to work...is there some trick to it?
I've purchased three tap tempo tremolo board sets (not all at once) and I seem to be having the same problem with each of them so far - the LED flashes correctly and syncs with the tap tempo switch input correctly, but I'm not getting any audio through the board. I've built two of the three boards now, and other than a couple of minor part substitutions, they are both exactly like the build document describes. Here are the part substitutions I've made, as they are what I had on hand:
C1 and C2 (right off the crystal) - 33pf instead of 22pf - does not appear to be affecting the LFO, or at least not the blink rate of the LED, which is right in time with the tap tempo switch
C9 (parallel to R15) - 470pf instead of 330pf - this one is the only one in the audio path, right?
C14 (at voltage regulator) - 470nf instead of 330nf
I re-touched all of the solder joints, and verified that there are no solder bridges.
Here are voltages at the OP AMP
1) 3.60v 8) 7.28v
2) 3.60v 7) 3.59v
3) 3.58v 6) 3.59v
4) 0.00v 5) 3.58v
Any help would be appreciated. I'm ordering the correct capacitors from Tayda now, I'm just concerned because I've built two already, and had the exact same issue with both of them.
Thanks,
Shawn.
(https://farm4.staticflickr.com/3767/13659063064_c633b7d7ac_b_d.jpg)
Those subs should be fine. The 1u caps are in the signal path too. Try building an audio probe and probing from the input to the output. The signal path is quite short so it should be simple to isolate.
If you're using a proper 9v regulated supply, you seem to have a problem with your 9v rail (pin 8 of the opamp).
Also, I recommend setting all trims and external pots to a middle setting while trying to get t to work.
Thanks, Taylor.
When I did the voltage testing, I was using a battery, though when "amp testing" I used a OneSpot, same results.
I'll build a probe and test it out...
Out of curiosity, I noted several small tinned holes on the board with no instructions on what to do with them (no parts to place, no jumpers listed, etc.). Are those test points of some sort?
Thanks again,
Shawn.
I've had an interesting issue come up. I recently bought a Timeline, and when I put the Tremolo on while the Timeline is on, I get a high pitched whine. I added filtering at the DC Jack, but didn't notice a difference. I've not had this issue with any other delays (including a El Capistan). I tried putting a buffered pedal between the two, no difference.
any ideas?
Quote from: sdb guitars on April 06, 2014, 10:23:50 AM
Out of curiosity, I noted several small tinned holes on the board with no instructions on what to do with them (no parts to place, no jumpers listed, etc.). Are those test points of some sort?
They are vias (http://en.wikipedia.org/wiki/Via_(electronics)). They connect traces on the top layer to traces or ground pours on the bottom layer. You can ignore them.
Quote from: lwatford on April 06, 2014, 07:48:36 PM
I've had an interesting issue come up. I recently bought a Timeline, and when I put the Tremolo on while the Timeline is on, I get a high pitched whine. I added filtering at the DC Jack, but didn't notice a difference. I've not had this issue with any other delays (including a El Capistan). I tried putting a buffered pedal between the two, no difference.
any ideas?
Hmm, it's possible that the PWM frequency of the trem is heterodyning with some clock in the Strymon. Might be something to ask Tom Wiltshire about (electricdruid.net)
Quote from: lwatford on April 06, 2014, 07:48:36 PM
I've had an interesting issue come up. I recently bought a Timeline, and when I put the Tremolo on while the Timeline is on, I get a high pitched whine. I added filtering at the DC Jack, but didn't notice a difference. I've not had this issue with any other delays (including a El Capistan). I tried putting a buffered pedal between the two, no difference.
any ideas?
What happens if you power the tremolo with a battery?
It does the same thing with a battery and/or separate power supply for the timeline. The half speed-ed squeel is around 10k, if that makes any difference.
Managed to get the trem working, but getting an ungodly loud pop when turning it on, every time. Works normally when turning it off. Is there a pull down resistor built into the board?
Yes. See the schematic for details:
http://musicpcb.com/documentation/
When do you use the 2N3904? I can't see it on there, it was on the bill of materials.
It's in the center of the board, below the trimpots. The flat side should face toward the trims.
so about 9 months after i mentioned it, i still can't access the site due to virus ???
Thanks for letting me know. There's no virus. Hackers keep hiding spam links in the site for SEO purposes. I fix it, they hack it again. People are still able to use the site regularly. If you're afraid of going on the site, you can always PM me regarding what you'd like to purchase and I'll let you know how to send a Paypal payment to me directly.
It's not that I don't care about this, it's that I don't know what to do to fix it permanently. Any suggestions are welcome.
Sorry to keep asking questions...I think I've just got clock noise bleeding through. I tried it with a different delay (DL4) and it did similar things when I dropped the loop speed. I also noticed that if I listened very carefully I could hear the whine in the background at all times with it on.
Thanks for all the help from various people on this post. Got it working (after some stupid mistakes) and it sounds great.
Also had my first go at etching a design in the enclosure. I used 1:1:1 mix of Hydrochloric acid (32%), hydrogen peroxide (40%) and water. worked great on a test piece but then on the actual enclosure, because its much larger it heats up a hell of a lot so speeds up the reaction, so I really over cooked it. There are probably a few other things I did wrong so it ended up looking a little scrappy, but luckily I was kind of after a worn effect so don't mind it so much.
(https://farm8.staticflickr.com/7189/13903845640_2643c25699_z_d.jpg)
Anyway, pedal works great. Well worth the build
The etch looks good! Also nice typeface for the controls, it goes well with the etch.
Building my first one in a week or so. Don't know if this has been asked yet, but I was wondering a few things.
1. What enclosure would be ideal?
2. There is a way to bring in external clock pulses, is there a dial of some sort that I could use to dial in a specific number?
3. I noticed many were having problems with "clicks", so I guess the only solution is involved with the LED's resistor?
Thanks.
The 1590BB is about the right size.
I don't understand your question about clock pulses - when you mention dialing in a number, what do you mean?
would it be possible to have a number to type in for the tempo speed? like 120 bpm or something. Maybe there's a way to send a tempo control to that.
That's not possible with the stock circuit/code. If you happened to have something like the Pamela's Workout module by ALM (this is a Eurorack synth module) then you could set the BPM on it and send 1ppqn clocks from it to the trem.
ok, then it's just a matter of putting a "clock in" 1/4 inch. Thanks! I hope I can try that. Anything I should be careful about?
I haven't done anything with that, but this might be a good question to ask Tom Wiltshire, who designed the TAPLFO chip that this project uses. His site is electricdruid.net.
Awesome. Can you double check to make sure you sent mine? I payed with paypal a while back. I'm in South Carolina.
hello all
i just built mine and it sounds great. the only thing i'm wondering is if there is a way to get the bottom of the swing to be completely null.
with my tremulus lune, with the depth set all the way up i could achieve no signal when the tremolo swing was in the off portion.
Can this be done with this design?
Resolved my question:
The NSL32 didn't have a high enough off state resistance to completely null the signal.
Switched to a Perkin Elmer and am satisfied.
I just wanted to pop in and say thanks to Taylor and everyone else in this thread. I got my board Monday evening, soldered Monday, boxed it Tuesday, took it to rehearsal on Wed. Worked first try and I have not even tweaked anything at all yet. Kudos!
(http://karywall.smugmug.com/Music/Tremedrone-Tremelo/i-Qp8HLwh/0/M/WP_20140603_010-M.jpg)
Nice, what's the symbol at the bottom?
It's from the Proto-Sinaitic alphabet....
http://en.wikipedia.org/wiki/Proto-Sinaitic
I had no reason for choosing "A" in this build other than I liked it, but in a previous build (quad buffer) I used that alphabet with "A,B,C,D" for the outputs.
Is the expected/required video allowed here? :icon_razz:
I finished this ages ago but forgot to post a pic. Fantastic effect !!
(http://s26.postimg.org/3ue4nbhx5/IMG_20140607_132339.jpg) (http://postimage.org/)
Just about done with mine, however, the 10R resistor right after 9v burned out. I can't figure out why, perhaps I'll try a different resistor. Has anyone else had this?
Most likely it was the fact that I used a 1/4w resistor. I'm switching to a 1/2w.
Argh... Same thing, the 10r just keeps getting hot when I plugin. Anyone have ideas?
Is your 4001 diode in the right way?
Well, I'm pretty sure it is, it's got the white side with the white on the board. I'll check again.
Edit:
Here's a pic
(http://i.imgur.com/s4k6fzWl.jpg)
probing around, there is no more resistor problems, but when I reach the op amp, the signal sort of dies, right after that third resistor. My guess is that nothing is getting the proper power it should. I might have messed up my regulator because of a crap dc adapter, don't think it was sending dc. :o
so I just finished the board, crudely threw some wiring for the offboard components to hear what it sounds like, plugged in and the good news is I'm getting signal. The bad is its terribly gainy, almost fuzz like. There's some serious gain going on here. Is this just the gain of the output that needs to be adjusted? (I was going to move the gain to the outside and didn't attempt to throw a pot on it yet to do an initial sound test)
Quote from: bluexskyxnoise on June 20, 2014, 10:09:13 PM
so I just finished the board, crudely threw some wiring for the offboard components to hear what it sounds like, plugged in and the good news is I'm getting signal. The bad is its terribly gainy, almost fuzz like. There's some serious gain going on here. Is this just the gain of the output that needs to be adjusted? (I was going to move the gain to the outside and didn't attempt to throw a pot on it yet to do an initial sound test)
yes. this needs to be set to a reasonable level, or can make the effect sound terrible.
when i built this, it fired right up no probs. i was skeptical because it was my first try at soldering ic's directly to the pcb without socketing them. super happy i have them soldering skillz to not overheat ic's or tranny's.
this thing sounds really nice! i am glad that i built it!
I just finished building three of these pedals, and I have the same issue with all of them. I've built a few dozen pedals before, but this is my first time building the tap trem. I've read the whole thread and I don't think my issue has been addressed, but I'm sorry if it has.
This is what happens:
Bypassed, the pedal works fine.
Engage the effect - it works fine, all features operate as desired (except that I couldn't get rid of 100% of the ticking on extreme settings, though I tried multiple optocoulers, changed the 330p to a 2.2n, and tweaked the pots)
After some length of time (sometimes 30 seconds, sometimes a couple minutes) there is a "pop" sound, and then a continuous buzz/hum with the ticking greatly amplifed. If I play while it is in this state, the guitar volume is reduced. The closest sound I can compare the buzz/hum to is when you have a cable plugged into your amp and you touch the other end's exposed jack tip.
If I disengage the effect there is another "pop" and the buzz/hum goes away, and I get my clean guitar signal.
Then if I turn the trem back on, after some length of time, it happens again. This happens to all three of the pedals I built.
One interesting thing to note is that the issue does not arise when I place a boost pedal (ZVEX SHO clone) after the trem.
This leads me to believe that there is some sort of issue with the effect out and my amp input, though I'm not sure what, since this is the first pedal I've built with this issue. When my amp (Fender Blues Deluxe Reissue) is on standby, I measure -0.5V DC at the input. When the amp is on, (not on standby) I don't measure any DC voltage. I unfortunately don't have access to another amp to try the pedal with for the time being. Is it possible that I need to use a polarized 1uF cap at the output instead of a film cap? Usually I use tantalums as the last coupling cap in my builds, but I went with a film for this one, as recommended in the build document.
Any help would be much appreciated, as I'm at my wits end here. I do not think there are issues with my work quality (solder joints, etc), since I have the same issue with all three pedals, and have done a very large amount of soldering on a variety of projects with no issues.
That's really weird. My understanding is that tantalum has less DC leakage than aluminum electrolytic but still worse than film, so if leakage is a problem I reckon polar would make things worse. Perhaps post pics and maybe somebody can see something of note.
Here are a few pictures:
(https://dl.dropboxusercontent.com/u/74890377/1.jpg)
(https://dl.dropboxusercontent.com/u/74890377/2.jpg)
(https://dl.dropboxusercontent.com/u/74890377/3.jpg)
Yours looks nice man! Just finished mine....
So the white dot on the opto is negative...
Hey All,
I'm on my 2nd Tap tempo tremolo build and have run across a problem. I have bypass signal but no signal when the effect is turned on. Checked all my connections and everything is hooked-up correctly. I have the LED hooked-up directly to the board so it should be on all the time w/ an offboard LED that engages & lights up when the effect is turned on. I am measuring 4.68v at both legs of the resistor side of the NSL-32 but no voltage on the + side leg (white dot leg installed in appropriate slot). So I desoldered & installed a 2nd NSL-32 (I have one more on hand) but same result: no voltage on + side leg & no voltage at POS. pad for the LED. Could both NSL-32's be bad?!
Does the flashing LED flash? If so, trace through the audio portion of the circuit with an audio probe until you find the point where signal stops getting through.
Bad parts exist but in my experience, my own mistakes outnumber bad parts 100 to 1.
Hi Taylor!
QuoteDoes the flashing LED flash?
No, flashing LED does not work - no voltage at positive LED pad.
OK, so the problem lies (at least) with the LFO section of the board. I'm assuming you've already set the trimpots to different levels while testing, set the knobs to various spots (always start with wave distort in the middle or 50% duty cycle, makes it easier to see things are working). Can you post voltages for the TAPLFO (PIC) IC and the 5v regulator (78L05)? A picture might also help us see something amiss.
I set external controls:Depth-2/3,Multiply-3/4,Wave -1/2(50%),Speed-3/4. I then adjusted all 3 internal trim pots (22k as listed in build doc., Board designation lists as 10K?) through entire ranges to no effect.
Here are my voltage readings for Tapflo:(from far left to right bottom row/then top row as in photo)
Pin #1- 5.01v #8- 0v
#2- 2.20v #9- 3.45v
#3- 2.13v #10-0v
#4- 5.01v #11-0v
#5- fluctuating voltage #12- 2.39v
#6- 0v #13- 2.50v
#7- fluctuating voltage #14- 5.01v
Voltages for 78L05:(from bottom to top refer to photo)
Pin #1- 9.34v #2- 0v #3- 5.01
Voltages for 2N3904:(from left to right)
Pin #1- .02-.04v (fluctuating) #2- .2-.46v (fluctuating) #3- 0v
Here's a gutshot...
(http://s25.postimg.org/w011xbhfz/Tupelo_Trem_Deluxe_Gutshot.jpg)
Just wanted to bump for a response. I tried different 2N3904's and 78L05's & adjusted trim pots to no avail - I'm still getting no voltage at the LED. I am however getting neg. fluctuating voltage at neg. leg of NSL-32 (dotted side). Any ideas would be greatly appreciated :)
Those voltages mostly seem reasonable, though I don't have a built tap trem at this time against which I could check. Since you said you built another one that works you should be able to compare voltages to see where they diverge and get a sense of where to look. The 3904 voltages possibly look suspect, any chance it's not seated firmly in the socket?
QuoteSince you said you built another one that works you should be able to compare voltages to see where they diverge and get a sense of where to look.
A friend of mine heard that pedal and relentlessly pestered me until I sold it to him. Fortunate for him, unfortunately for me! So I don't have anything to compare voltages to.
I made sure to seat the 3904 properly when I replaced it with another from my stock.
A couple of things I noticed that maybe you could clarify:
1. I am getting 4.68v only on topside leg (resistor side of NSL-32) bottomside leg reads 0v. Is that correct?
2. Dotted side of NSL-32 voltage fluctuates between -(negative).02-.07v. Positive leg reads 0v. Does that seem right?
3. Could voltage to the LED be blocked at the trimmer pot?
New 2N3904 reads (from left to right) : pin#1 neg(-) .01-.06v fluctuating, pin#2 .16-.52v fluctuating, pin#3 0v.
Bump for reply - anyone with a working build, some voltage measurements?
I would, but it seems like I killed the taplfo somehow. I don't see any voltage out of pin 5, input voltage looks right.
Here is my fourth take on the MusicPCB Tap Tempo Tremolo / Gigatrem
This was a bitch to get rid of the tick, dont think ive totally managed it to be frank.
It only affects the ramp, which you can avoid by selecting triangle and wave distort it for the same sound, the square wave and random
I decided this time to do the "resistor string on rotary dial"
If I were to do this again Id probably skip a few modes with the correct resistor values for convenience sake.
I have no plans for this other than to probably pass it to my cousins husband who was asking me about trems a while ago.
He likes classic sine wave trem, so the tick on teh square and ramps wouldnt bother him as I doubt he would use those modes
The other thing I did new for this build was add a small momentary multiplier step switch which skips the rate set by the tap tempo through various subdivisions. neat!
Enjoy pics
(http://i1178.photobucket.com/albums/x374/LaceSensor1/IMG_0763_zps61751fe8.jpg)
(http://i1178.photobucket.com/albums/x374/LaceSensor1/IMG_0762_zps351a264c.jpg)
Building this for a bass player. In/Out caps need any adjustment. They are fairly large at 1uf, but thought I'd ask.
I just simulated it with the Falstad Filter App (http://www.falstad.com/afilter/), with the values in the schematic it's flat to way below bass's lowest fundamental, so no need for bigger caps. In fact, it could be 100n and wouldn't be rolling off any appreciable bass.
Thanks, Taylor. Hard to believe this thread started 4.5 years ago with our posts! HA! Lace, did you use the NSL32 or roll your own? I ordered a slew of ldrs with the specs you use in the doppel and was going to give it a shot.
Quote from: jmasciswannabe on October 14, 2014, 08:33:57 PM
Thanks, Taylor. Hard to believe this thread started 4.5 years ago with our posts! HA!
Yeah, that is crazy, and even though I know a lot now that I didn't know then, I'm glad my posts on the first page don't seem dumb to me now. There's stuff still up on the internet that I wrote last millennium when I was 13, ranting about Ralph Nader. Now
that is too embarrassing to link. ;D
Quote from: jmasciswannabe on October 14, 2014, 08:33:57 PM
Thanks, Taylor. Hard to believe this thread started 4.5 years ago with our posts! HA! Lace, did you use the NSL32 or roll your own? I ordered a slew of ldrs with the specs you use in the doppel and was going to give it a shot.
Guess I could have answered my own question by taking a look at the pic closely! :icon_rolleyes:
Hey guys. I read through a great deal of this thread and didn't see anything jump out at me with respect to my issue.
I built the unit and tried out a few different vactrols. A little bit of ticking, mostly only in the ramp up/down and square settings. But it's really only noticeable when no music is being played. I'm currently using about 4.3nF to try to buck the ticking.
Sure I'd love to kill the ticking entirely, but that's not the meat of my main issue.
If I tap a tempo in. All is well.
Then if i adjust depth or waveform, the tempo immediately reverts back to that of the tempo potentiometer setting.
-in fact, sometimes i'll tap in the tempo using very slow and deliberate taps. and then within say 2 or 3 seconds it'll automatically revert back to the pot setting as well.
Any help or pointing to other post would be greatly appreciated.
Thanks all!
Try measuring the voltage at pin 13 of the TAPLFO chip - the tempo pot ADC input - while moving the other knobs that cause this problem. Seems like maybe there's a bridge from those other pots leaking into the tempo pot. When the tempo pot is moved, the chip is designed to snap to the knob value, so I suspect there's some noise or bleed there that causes enough change in the tempo CV to make the chip think you're moving the pot.
Thanks Taylor. I'll measure it up. When you suggest a possible bridge are you meaning in the chip itself?
There certainly isnt any physical bridge seen during inspection between any of the pots / rotaries or any of the pads.
I actually did measure this earlier today. Pin 13 seems to stay stable throughout the process.
It is almost as if the PIC is deciding that there is not a tap switch connected. ie: if you were to hook the switch up with jumper clips tap in a tempo and then remove the jumpers the unit would revert back to wherever the tempo pot was set.
This is an intermittent thing but without fail it will happen each time i turn it on. almost immediately. I have tried different switches as well. same issue.
If it were bleed or cross talk from the other controls how would i troubleshoot / confirm?
The tap switch is a normally open momentary type, so when you aren't pressing it down, as far as the TAPLFO is concerned the switch could be gone. I didn't write the code but I don't know of any other input condition that makes the chip switch to the tempo pot's value, other than when it thinks you've moved the pot. You could try emailing Tom Wiltshire (electricdruid.net) to see if there's another reason it would do that, which would give you an idea of where to look.
One other direction to look from: it's not clever about averaging the last few taps. It wants to measure between two taps only. If you tap thrice, on the third tap you've just re-initiated the time measurement. It will only listen for some period (I think ~10 or 20 seconds but it should be in the datasheet at Tom's site) before reverting to the tempo pot value. Maybe this is happening when you tap in an odd number of taps?
Taylor,
I tried to open your web site, but my antivirus blocked it saying:
Location: musicpcb.com
Access has been blocked as the threat Troj/SEO-A has been found on this website.
I thought I'd better let you know! :)
Thanks LPL, it's been an ongoing problem, see here for an explanation:
http://www.diystompboxes.com/smfforum/index.php?topic=89687.msg996939#msg996939
Hi there
I'm just doing a bit of tinkering and wondered if anyone could tell me what the two EXP pads for the optional multiplier switch connect to on the PCB? Looking at the schem it looks like one goes to pin 8 of the TAPLFO and the other to ground. This could be completely wrong though as I am useless at reading schematics.
All help greatly appreciated.
Thanks
That's right, so a momentary switch across those pads will pull pin 8 of the TAPLFO low, which steps up to the next multiplier. The pin is normally pulled high through the 10k resistor directly above the EXP pads.
Ok so after not working on pedals for a while I've decided to get back into it and I want to fix my tremolo pedal. This was one of my favorites that I made. But right now I'm not getting any sound through the pedal. I have it hardwired without a switch till I get it fixed.
Not only am I not getting any sound what so ever. I've checked the voltages on the tap Lfo and it seems to be within the parameters as everyone else's. So what could be causing it?
It could be anything in between the audio input and audio output. The audio section is the TL072 and right side of the board. The first step would be to build an audio probe (http://www.diystompboxes.com/wiki/index.php?title=Debugging) and probe from the input all the way through, using the schematic as your map, until you find the point where you stop getting sound. Checking opamp inputs and outputs is a good place to start to narrow down the area of interest. Also a good idea to put trimpots and wave distort knob to a middle position when testing.
Evening all,
Just finished off the circuit and I amp having an issue with the audio side. After a quick probe around I loose my signal at pin 2 of the TL072. I socketed the 072 and if I remove it I can probe and get the signal when pin 2 would be, so it must be something odd with the IC or its biasing. I'm wondering if my Vref is too high?
Here are my voltages:
1 - 3.68 8 - 7.39
2 - 3.68 7 - 3.68
3 - 3.66 6 - 3.67
4 - 0.00 5 - 3.66
Vref - 3.66
This is with a battery hitting 7.5 volts. This figures are the same proportionally using a 9v PSU.
Any ideas?
Also, just to clarify, the NSL32 has the white dot on the negative leg, correct? So it should go into the lower hole on the LED side of the pcb (lower left).
Quote from: Joe Dorcia on March 04, 2015, 06:14:45 PM
Evening all,
Just finished off the circuit and I amp having an issue with the audio side. After a quick probe around I loose my signal at pin 2 of the TL072. I socketed the 072 and if I remove it I can probe and get the signal when pin 2 would be, so it must be something odd with the IC or its biasing. I'm wondering if my Vref is too high?
Here are my voltages:
1 - 3.68 8 - 7.39
2 - 3.68 7 - 3.68
3 - 3.66 6 - 3.67
4 - 0.00 5 - 3.66
Vref - 3.66
This is with a battery hitting 7.5 volts. This figures are the same proportionally using a 9v PSU.
Any ideas?
Actually, we expect pin 2 (inverting input of the first opamp) to have no audio signal because that point in an inverting amp is a "virtual ground." Here's a good video that will explain this:
https://www.youtube.com/watch?v=7FYHt5XviKc (https://www.youtube.com/watch?v=7FYHt5XviKc)
So it showing your Vref voltage is correct as the non-inverting input is at Vref and the opamp attempts to make its inputs equal through feedback. Your Vref should be half the supply voltage, which it is so you're good there.
So, the voltages you posted look fine, but they don't tell the story of what's going on with the audio since you presumably were not playing anything into it while measuring, and a multimeter is not a very useful tool for looking at audio anyway. Continue probing - next check the output of this amp (pin 1) for audio, then the output of the output amp (pin 7).
QuoteAlso, just to clarify, the NSL32 has the white dot on the negative leg, correct? So it should go into the lower hole on the LED side of the pcb (lower left).
Yes, that's right.
Quote from: Taylor on March 04, 2015, 08:20:19 PM
Quote from: Joe Dorcia on March 04, 2015, 06:14:45 PM
Evening all,
Just finished off the circuit and I amp having an issue with the audio side. After a quick probe around I loose my signal at pin 2 of the TL072. I socketed the 072 and if I remove it I can probe and get the signal when pin 2 would be, so it must be something odd with the IC or its biasing. I'm wondering if my Vref is too high?
Here are my voltages:
1 - 3.68 8 - 7.39
2 - 3.68 7 - 3.68
3 - 3.66 6 - 3.67
4 - 0.00 5 - 3.66
Vref - 3.66
This is with a battery hitting 7.5 volts. This figures are the same proportionally using a 9v PSU.
Any ideas?
Actually, we expect pin 2 (inverting input of the first opamp) to have no audio signal because that point in an inverting amp is a "virtual ground." Here's a good video that will explain this:
https://www.youtube.com/watch?v=7FYHt5XviKc (https://www.youtube.com/watch?v=7FYHt5XviKc)
So it showing your Vref voltage is correct as the non-inverting input is at Vref and the opamp attempts to make its inputs equal through feedback. Your Vref should be half the supply voltage, which it is so you're good there.
So, the voltages you posted look fine, but they don't tell the story of what's going on with the audio since you presumably were not playing anything into it while measuring, and a multimeter is not a very useful tool for looking at audio anyway. Continue probing - next check the output of this amp (pin 1) for audio, then the output of the output amp (pin 7).
QuoteAlso, just to clarify, the NSL32 has the white dot on the negative leg, correct? So it should go into the lower hole on the LED side of the pcb (lower left).
Yes, that's right.
Thanks Taylor, its all up and running now! As I didn't fully understand how the IC was working I focussed on that instead of just replacing the Vactrol - must have been a dud or I accidentally fried it (unusual, not fried any diodes or trannies before but who knows). Anyway, its sounding great now, a bit of fiddling to do as there is still some ticking on the Ramp Up and Square settings - I also wired my external gain pot backwards so I'll sort that too.
In the build doc you suggest a Ultra Bright Blue LED, I used UV/purple for mine for aesthetic reasons but I know they have a much lower brightness rating than blue. Why did you suggest blue? To allow you to use a lower voltage and it still be bright? Would it be worth me swapping the UV/Purples for something brighter?
Hmm, I think my thinking at the time had to do with using less current to turn on the LED, since the current spikes when switching the LED are one of the sources for ticking in the audio in trem circuits.
But, there are so many variables in DIY builds that I don't know that it matters too much. If you're unable to trim out the ticking you could try swapping in a high-intensity LED to see if it makes a noticeable difference.
Quote from: Taylor on March 05, 2015, 09:52:56 PM
Hmm, I think my thinking at the time had to do with using less current to turn on the LED, since the current spikes when switching the LED are one of the sources for ticking in the audio in trem circuits.
But, there are so many variables in DIY builds that I don't know that it matters too much. If you're unable to trim out the ticking you could try swapping in a high-intensity LED to see if it makes a noticeable difference.
Thanks again, I might swap the UV LEDs out for Warm White. Both are Ultra Bright, but the UVs brightness is rated at 3,000mcd, Warm White is 14,000mcd (Blue is 9000mcd) so that may help. Once its all done and looking lovely I'll post a pic.
Big thanks to you and Tom for designing such a great circuit and tap LFO chip, it sounds wonderful!
Anyone got that alternate wiring diagram picture? I believe I just need to Ground the PWM when switched to get rid of that nasty tick.. and somehow make my LED less blinding.
I redrew the alternate bypass diagram, here's the file, and it's also linked on the tap trem page at the musicpcb site, so you can find it without having to find this particular page of the thread.
http://imgur.com/fi592fn
To make your LED less bright, you just need to turn down its associated trimpot. That's the one in between the ICs, on the right.
Thank you!
I should add this: the extra LED in that diagram will work like a regular bypass LED - it doesn't show the LFO's activity like the one on the board. But the one on the board will turn off when bypassing anyway, so this second LED is optional. Some people wanted this because in certain settings (square wave, tiny pulse width) the LED is not so visible when flashing. So for anybody using this alternate wiring scheme, if you don't want the second LED just leave it and its resistor off, leave the lug it was connected to on the bypass switch empty.
I just switched that resistor connection to gnd in off mode and it worked great :D
Hi there,
I am using and loving my tap-tremolo very much, but two things I'd really like to change. First thing: I only use the sine and the square waveforms. I think I figured out how to wire a spdt switch to only have these two waveforms. Maybe someone has a better idea?
(http://i1244.photobucket.com/albums/gg578/lars-musik/Waveform.jpg)
However, I'd also like to get rid of the triplet settings of the multiplier and here I completely lack ideas. What I have in mind is a switch that switches between half, normal and double tempo compared to the tap. Can anybody help?
Thanks in advance!
For the sine/square switch, you could wire three resistors in a chain and swap between the nodes between R 1 and 2 and R 2 and 3. After a long Saturday of work my brain's too fried to think of the right resistor values at the moment though. This would only save you a resistor.
A rotary switch with only those three multipliers would be simple - again you'd just wire the resistors in series and connect the throws of the switch to the nodes between resistors. Just pick the right resistor values to only select the values you want. A toggle switch could also be done but most 3-position toggles are center off, so you'd need to pull the center multiplier pad low in the center position with another resistor, and then your toggle would be normal speed, then half speed in the middle, then double speed. You can get 3-position toggles with an actual third throw if having them out of order bugs you, but the only ones I remember seeing have the sort of cylindrical lever which requires an elongated hole drilled through the enclosure, which makes them inconvenient for most DIYers as cutting a slot is tricky to do.
I am almost certain this has been covered. I have searched and not found an answer.
1. Is there a way to search an individual thread?
2. Should the momentary switch be NC or NO?
3. When set at 1/4 Notes, what is the longest tempo that can be tapped in? Can you tap in as slow as the tremolo pot can set? Is there a point where the last tap is ignored as too much time has passed and a 2nd tap has not occurred?
Thanks
1. No, and I agree this does make using this thread somewhat difficult. I usually have better results using Google to search this forum rather than the built-in search. So for example something like
"momentary switch" "tap tempo tremolo" site:diystompboxes.com
2. The switch should be normally open.
3. Here's what the TAPLFO chip datasheet (http://electricdruid.net/datasheets/TAPLFO2Datasheet.pdf) has to say:
"The basic range of the TEMPO CV allows the LFO to produce frequencies between 0.05Hz (a 20
second cycle) and 12.8Hz. However, in conjunction with the MULTIPLIER CV, this range is
extended to 0.025Hz (a 40-second cycle) to 100Hz."
There is definitely a timeout on the taps such that after some amount of time the chip stops waiting for a second tap and just goes back to the time defined previously, but I couldn't find how long the timeout is even scanning through the assembly code for a note. Emailing Tom Wiltshire would be the most direct route to an answer. His email is here:
http://electricdruid.net/index.php?page=projects.taplfo
Thanks taylor.
I actually recently purchased and installed a new pcb due to all the bizzaro issues i was having with my original one. I've emailed Tom as well.
At this point, my main issues are the ticking. Which i will deal with i'm sure. (on that topic - i'm wondering how much the current draw of the LED selected for the tempo indication impacts the ticking? - I know a blue is recommended, why?)
And lastly, perhaps the momentary switches i've tried just aren't that useful? I mean, I can't see tapping less than 4 taps in general. It is rather difficult to only tap twice when setting a tempo in quarter notes!!
Check the last page for some talk about the LED and current, but I can't say precisely how much of a difference the selection of LED makes here. Sorry, I didn't really understand what you mean about your switches not being useful. Are you having an issue with the switches themselves, or do you mean you wish the TAPLFO would average over the last four taps for example? I can see how that behavior could possibly be more usable. That would require a code revision, which I don't know if Tom or anybody else has plans for right now. I'm no good with assembly code for now (hope to find time to work on it at some point) but perhaps someone on this forum will give it a try?
I just finished my build but have ran into some issues. When I plugged in the power supply the 10r resistor (next to the diode) greeted me with a nice puff of smoke and appears to be slightly roasted on the outside?! Also, I noticed the tempo LED did Not come on. The bypass LED functioned properly. Any ideas?
The 10r resistor feeds power to the whole circuit so if it burnt out then nothing on the board will be getting power, so that explains why the LED is not flashing and presumably you have no signal through the circuit. Are you using a 1/4 watt resistor there? Some other things I can think of would be if you had installed the 5v regulator or one of the chips backwards, possibly something there would try to pull a lot of current and let the smoke out of the 10r resistor. It can be tough to solve these mysteries from afar but I suspect the 10r will keep burning up if you just replace it; there's probably a part in wrong that's making the circuit try to draw a lot of current, or a short to some pin carrying power.
Am I correct in having the dot on the opto on the bottom right side (negative)?
Also here is a picture of the board. You can see the roasted 10r resistor. Anything look off? Any ideas?
(http://i3.photobucket.com/albums/y78/stretch-armstrong/Mobile%20Uploads/image.jpg) (http://s3.photobucket.com/user/stretch-armstrong/media/Mobile%20Uploads/image.jpg.html)
Yes, if it's an NSL-32 the dot is negative. I don't see anything off there. Perhaps if the trimpots in the center of the board are all the way to one side then the opto and/or LED pulled too much current. Try setting them to the center until you get it working, then you can tweak them. You can actually replace the 10r resistor with a jumper wire to at least get power to the circuit so you can take some measurements with a multimeter. This will help you focus on where the issue lies. The 10r is there to filter power (in conjunction with the caps to the right of it) and decouple the power the supply from the circuit, but it will function if the resistor is replaced with a link. Then you can measure voltages on the ICs and transistor and regulator.
The I had the nls-32 backwards during the first fire up so I think I roasted it also. I have it installed correct now.
I put a jumper in place of the 10r and get nothing but a tick. The bypass signal comes through but that's it. No LEDs light up.
I used this diagram to wire up the switch. I did this to have a tempo led (directly off the board) and a bypass led. Was this wrong?
(http://i3.photobucket.com/albums/y78/stretch-armstrong/image.jpg2.jpg) (http://s3.photobucket.com/user/stretch-armstrong/media/image.jpg2.jpg.html)
If you've got a tick coming out of the output it may be working and you just need to tweak the trimpots, experiment with the controls and make sure the width knob is centered while testing. Check the top of this page, below the DIYSB banner as well as the main "building your own stompbox forum for sticky links for debugging. Build an audio probe and check through the circuit, and measure voltages with your multimeter.
That bypass wiring should work just fine, no conflicts.
Hey everybody. First stompbox build for me ever. I made a real noob move and didn't pay attention to the wattage values for the resistors when I was searching on mouser... ended up with GIGANTICLY sized components. They are the correct resistance values, but they're just huge. Having some issues, hopefully it's an easy fix. The unit is humming both in bypass and active. I can hear my guitar when bypassed, but it hums bad. I can barely hear the guitar when active, but the hum is worse and the guitar sounds super faint and distorted. Also, the LED wired directly to the PCB never flashes, just nothing from it. I followed this wiring diagram for the switch: http://imgur.com/fi592fn
Here's images of my build in it's current state:
http://i.imgur.com/CKIoSNM.jpg
http://i.imgur.com/O9DqDWx.jpg
It doesn't look like the 9v and ground pads on the pcb are connected to your power jack. Is that how you have it?
No I don't have those pads wired. The alternate wiring method I used made it seem like those pads weren't used. So... I would need to wire from the power jack to the pads on the board and have another wire from the 9v lug on the power jack go to second LED?
Sorry for noobishness. This is indeed my first stompbox build. The only other electronics I've done have been pickup replacement and wiring a keyboard matrix to a teensy.
Got it working. Still buzzing/humming, just not as bad. I can hear the guitar signal, both LEDs work as expected, and best of all it actually trems and all the knobs and switches function. Is the buzzing probably a ground issue? Like maybe it'l go away when I put it in the metal box and the 'In' jack is grounded against the box? Also, I've seen mention of using a TRS stereo jack for 'In' and mono for 'out'. Currently I'm using mono for both. It looks like that's only really needed if one using both a DC jack and a battery?
OK, sorry about that, that diagram is only meant to replace the bypass wiring so it doesn't have any of the other stuff shown. The PCB for any effect will always need to be connected to power and ground and all the grounds for the whole thing should connect together.
Yes, hum can often indicate some problem with grounding, like not all of the grounds are connected together, and also depending on your house wiring and e.g. if there are fluorescent lights or other things in the room throwing out a lot of electromagnetic noise, the circuit will pick it up if it's not shielded by being inside a grounded metal enclosure.
For the stereo jack, people only use them when they want to be able to use a battery - the stereo jack is wired not actually to accept a stereo signal, but used like a switch to only connect the battery when there is a 1/4" cable inserted into the pedal. This saves the battery from draining when you're not using the pedal, because most pedals have no way to actually turn the circuit off - the bypass switch only reroutes your audio signal but does not power down the circuit when in bypass. So you don't need to use the stereo jack if you don't want to use a battery.
Gotcha that all makes sense. One last thing, I hope... should the tempo led that's wired directly to the board always be on and blinking when the circuit has power? Regardless of whether it's in bypass or not?
Well, with the alternate bypass which you used, the LFO gets shunted to ground when in bypass. The point of that was that some people's builds would tick even in bypass so this stops that. But it also means that the LED doesn't light up in bypass because the signal that would usually light it up is not present. So the extra LED which is wired to the bypass switch is there to show that the effect is on even with e.g. minimum depth or narrow pulse width which makes the blinking LED hard to see. Yet another version of the bypass could be done without shunting the LFO but adding the second LED, so that the flashing LED would stay on during bypass in case you wanted to set the tempo while bypassed - this would not stop the potential for ticking in bypass though so you'd need to fuss a bit more over tweaking the trims and keeping wires short.
Hah, I put it a box and now it doesn't make any sound. Oh jeez. I've double checked that everything is wired right. I did have a noob oopsie moment and stripped the pad off one side of the board whilst trying to remove a pot lug. These are double sided pads though, so as long as one side is still there it shouldn't matter to much right? I've provided a picture, but I dunno how well anybody will be able to see, it's a birds nest in there. Are there any general troubleshooting steps I can take to find the issue?
http://i.imgur.com/9bIDJmo.jpg?1
Quote from: tuffrabit on April 28, 2015, 03:26:53 PM
Hah, I put it a box and now it doesn't make any sound. Oh jeez. I've double checked that everything is wired right. I did have a noob oopsie moment and stripped the pad off one side of the board whilst trying to remove a pot lug. These are double sided pads though, so as long as one side is still there it shouldn't matter to much right?
Which pad is it? There are two layers of copper traces, one on each side, which are different, not copies of each other. Some pads connect only to the bottom layer of copper, others to the top, some to both. So for example the center pad for the multiply knob only connects on the top layer, you can see it goes nowhere on the bottom. But the outer two pads both connect on the bottom, not the top. If the bottom pad of the center lug came off, doesn't matter. The bottom pad of either of the outer lugs coming off would mean the connection is cut.
QuoteI've provided a picture, but I dunno how well anybody will be able to see, it's a birds nest in there. Are there any general troubleshooting steps I can take to find the issue?
Yes, check the links at the top of this page, right below the diystompboxes banner, as well as the sticky links that are the top posts in the "building your own stompbox" forum (that's the one this thread is in). Using a multimeter start by verifying you've got e.g. power on the IC pins that need power, that all the grounded points on the board and the external parts are connected together, then build an audio probe based on the debugging links above and test through the circuit starting at the input and checking the outputs of major bits like the opamps, and see where you lose signal. You didn't say the LED stopped flashing so that means everything on the left side of the board (viewed from the front) is OK. You just need to check through the audio stage on the right around the TL072 and the optocoupler.
It's the middle lug of the waveform pot on the bottom of the board.
Thanks, I'll check out that link and start troubleshooting.
If it makes a difference or not, but I'm not getting any sound out of it either in active or bypassed mode. I wonder if the switch is bad.
I don't get it. The bypassed signal should be working. Using a multimeter I can verify continuity between the tips and sleeves of each jack when the switch is in bypass. Weird.
Finally finished this.
Here's a picture...
(http://images.tapatalk-cdn.com/15/04/29/8cd06d3562d6a4c190b7c8ffd99ba941.jpg)
Cool, is that Niko?
K, noob questions time.
Should there be or not be continuity between the tip of one jack and the sleeve of the other jack (or general ground)? I'm guessing there should not be... but there is. So I've got a short somewhere?
Figured it out. The output jack tip was just barely touching one of the pot housings.
Quote from: Taylor on April 29, 2015, 11:38:31 PM
Cool, is that Niko?
It's not Niko, but it is from GTA V.
Los Santos Customs 8)
Yay! It's mostly working now. I got rid of the ticking by using an old guitar lead for shielded lines for the input and output jacks. Now it does this thing where it will be fine for a time, then it will pop loudly then loose 40 - 50% of it's volume and take on this scratchy squealy quality. Going to bypass and then back on "fixes" it for a time. I have a theory that maybe the PCB is moving on the inside of the enclosure and touching stuff it shouldn't, but that may or may not be the issue. I made a video of this happening (I just now uploaded it, so it might still be processing):
based on what you said, It is incredibly likely that the pcb is wobblin' around in there. Try to secure it.
I've been in the process today of making a new PCB for the TTT to allow for our rotary needs. I also wanted to cut out the time it takes to hand wire pots and just have a PCB with mounted pots.
Here's the schem I have so far with two rotarys. Sorry for the sloppiness, it's a first draft. Any revisions seen here are appreciated.
http://i.imgur.com/IRDCNQA.png
Fun build. I was careful and I didn't have to do much trouble shooting! I hung the TapLFO LFO circuit off mine to use with my Moog stuff.
http://www.radioles.com/works/tttlfo1.jpg (http://www.radioles.com/works/tttlfo1.jpg)
http://www.radioles.com/works/tttlfo2.jpg (http://www.radioles.com/works/tttlfo2.jpg)
Thanks for the great project and all the help from Tom Wilshire, too. Joe.
There are a few questions I would like to ask you regarding the tap tempo tremolo build as far as modifications are concerned. Being the type of person that I am, I enjoy being able to apply as much to the pedal as possible for as much versatility with the least amount of unwanted noise as a result:
1)
Expression pedal input - I would like the ability to apply an expression pedal input to the build that monitors both the optional Rate and Depth of the LFO. I'm aware that what I would have to do is apply an On-On toggle switch somewhere within this, but I'm not exactly sure how to go about effectively following through with the off-board wiring to achieve the effect. At the very least, I would like to be able to affect the Rate of the LFO with an external expression pedal as well as having the tap tempo footswitch where it would be expected, so is there a certain way I might need to wire the pedal for this effect other than what you had suggested in this post:
Quote from: TaylorSimply wire a jack to the 3 pads of the pot you want to replace, making sure that you wire it to be in compliance with the expression pedal you're using (they're all wired differently). Use a switching stereo jack so that when you unplug the expression pedal, the pot becomes active.
2) I would like to be able to apply a
Tap-In to sync with an external multi input tap tempo switch that I would have on my board so that I can set the tremolo's modulation speed to the exact speed as my Hungry Robot's Starlite Reverb modulation once I have them both connected to each input within the separate tap tempo pedal. Is this what was being referred to as the last suggested modification on the build page referencing "Using the Tap Tempo LFO as a synch-able LFO" or will I have to apply something different?
3)
LFO speed-monitoring LED and
status LED - Just for clarification, if I wanted to have the LFO Rate LED continue flashing in bypass so that I may affect the speed while the status light is off, all I need to do is simply attach the postive and negative leads to the board itself where the "Neg" and "Pos" slots are located, correct? Or is there something else that I might need follow along with in order to achieve this?
I'm aware that I'll probably just have to a second LED in the traditional way most are wired through true bypass means in other pedals with the appropriate resistor if I wanted a status LED.
4) Finally, I'd like to know if it's possible for me to have
all three of the Multiplier Knob (I'm going to be using a 1P6T switch if possible), Multiplier footswitch AND the On-Off-On Range Switch options applied within the circuit together? I had read that the range switch was to be used of the Multiplier knob was no longer necessary, however if I still wanted to utilize the Multiplier knob and still have access to the Range Switch for mor versatility, I'd love to.
I just needed to ask you these questions before I finished ordering so I know as to whether or not any of it would be possible. I'm hoping I'm not fantasizing beyond the realm of capabilities this circuit has to offer.
Thanks,
- Andrew C.
Andrew B. Campbell, That all seems do-able. Look at the schematics for the TapLFO chip from Tom Witshire. Every pot can have a jack to a expression pedal. And the TapLFO can be wired to take an external sync. And if you wire the on off switch as in the pdf, the Taplfo output is not grounded only bypassed so you can use the LFP circuit when the tremolo is bypassed. Joe.
Quote from: Andrew B. Campbell on August 11, 2015, 09:59:10 PM
1) Expression pedal input - I would like the ability to apply an expression pedal input to the build that monitors both the optional Rate and Depth of the LFO. I'm aware that what I would have to do is apply an On-On toggle switch somewhere within this, but I'm not exactly sure how to go about effectively following through with the off-board wiring to achieve the effect. At the very least, I would like to be able to affect the Rate of the LFO with an external expression pedal as well as having the tap tempo footswitch where it would be expected, so is there a certain way I might need to wire the pedal for this effect other than what you had suggested in this post: Quote from: TaylorSimply wire a jack to the 3 pads of the pot you want to replace, making sure that you wire it to be in compliance with the expression pedal you're using (they're all wired differently). Use a switching stereo jack so that when you unplug the expression pedal, the pot becomes active.
There are a couple of ways to do it. Decide first if you want the expression pedal to
add to the panel control, or to replace it whenever the expression pedal is inserted.
If you want to add to the panel control, using it to set the minimum speed for example, from which you'll sweep up, this will be more complicated as you will need to add an active summing stage for each control. That means extra components which you would wire on perf board or similar. Basically you need a little CV mixer which mixes the CV coming from the panel pot with that coming out of the expression pedal.
If you are OK with the expression pedal taking over completely for the panel control when the Exp. is inserted, then just use a stereo switched jack like this:
http://smallbear-electronics.mybigcommerce.com/1-4-in-stereo-nys212/
When you get one in hand, notice that when you insert a jack, three little metal arms rise up - these are the contacts for sleeve, ring, tip (in order of rising). The other ones, which don't move, are the switch contacts. You would connect the wiper of your panel pot (disconnected from the PCB) to the tip switch contact, then the [tip, ring, sleeve] connections to [the center pad for the control you're replacing, 5v, and ground] respectively. Now, when no plug is inserted in the jack, your panel control is active, but when it's inserted, the pot's value is no longer sent along to the TAPLFO and is replaced with that coming from the expression pedal.
Quote2) I would like to be able to apply a Tap-In to sync with an external multi input tap tempo switch that I would have on my board so that I can set the tremolo's modulation speed to the exact speed as my Hungry Robot's Starlite Reverb modulation once I have them both connected to each input within the separate tap tempo pedal. Is this what was being referred to as the last suggested modification on the build page referencing "Using the Tap Tempo LFO as a synch-able LFO" or will I have to apply something different?
You just need to wire this jack in parallel with the tap switch, or if you only want to do the tapping from the external box, connect a jack instead of the tap switch. Left TAP SW pad goes to jack sleeve (ground), the right to the tip of the jack.
Quote3) LFO speed-monitoring LED and status LED - Just for clarification, if I wanted to have the LFO Rate LED continue flashing in bypass so that I may affect the speed while the status light is off, all I need to do is simply attach the postive and negative leads to the board itself where the "Neg" and "Pos" slots are located, correct? Or is there something else that I might need follow along with in order to achieve this?
I'm aware that I'll probably just have to a second LED in the traditional way most are wired through true bypass means in other pedals with the appropriate resistor if I wanted a status LED.
Yep, you've got it right.
Quote4) Finally, I'd like to know if it's possible for me to have all three of the Multiplier Knob (I'm going to be using a 1P6T switch if possible), Multiplier footswitch AND the On-Off-On Range Switch options applied within the circuit together? I had read that the range switch was to be used of the Multiplier knob was no longer necessary, however if I still wanted to utilize the Multiplier knob and still have access to the Range Switch for mor versatility, I'd love to.
I just needed to ask you these questions before I finished ordering so I know as to whether or not any of it would be possible. I'm hoping I'm not fantasizing beyond the realm of capabilities this circuit has to offer.
Thanks,
- Andrew C.
I'm actually not certain to what you're referring specifically when you say range switch, but I think maybe you're talking about just using the toggle to select from a couple of multipliers instead of having the rotary switch/pot control. So you wouldn't be gaining anything by having both. However, you can totally have the Multiplier knob/rotary switch plus the Multiplier foot switch together in a single build, no issues there.
I thank you for the response. I can visualize what you've suggested.
Disregard the "Range" switch. For some strange reason, I had misread the .pdf and thought it performed something in a different manner than what I'm almost positive it actually does.
As far as the expression pedal is concerned, I really don't mind if the the secondary pedal replaces the rate or depth knob in this instance because if I need a specific speed after having altered it drastically with the expression pedal, all I'll have to do is tap that in with the momentary switch to arrive at the tempo that I need. What I had still wanted to do with this was have the ability to switch between which features I wanted to manipulate with the expression pedal alone, similar to something like this if it were possible.
This is literally the only inquiry I have left then. If this isn't possible with one input jack, will I have to apply a second and skip using a toggle switch altogether? The only thing I'm worried about is that if the toggle switch to change between either Tempo or Depth expression is that if one is selected and the expression pedal is inserted into the expression input, still both knobs might be disabled even though only the one selected feature is being manipulated. I'm fairly new at all of this, so I'm not sure if there's a way to bypass the Depth knob so that it still maintains its function if the toggle switch is selecting the Tempo expression while the external pedal is connected (and the same applying the other way around) or if I'm just making this much too complicated.
http://imgur.com/9Jwbotb
I believe this should do it for you. I couldn't think of a way to do it with just a DPDT switch as in your drawing. Maybe somebody else can think of a more clever way that uses only two poles, but the solution drawn here needs three - one to switch the tempo control input between the pot and the exp., one for the depth, and one to connect either the tempo or depth pot's wiper to the switch on the jack.
Note that I've drawn the toggle switch with the lugs oriented the way they are on a real switch, so the switch drawn toggles up and down. Might be confusing because the lugs are drawn the other way on your drawing, so it might look like I've turned the switch sideways (and it's harder to read orientation on the 3PDT because of the rotational symmetry).
This is simpler than with most pedals because of the rare fact that this pedal's controls are all just voltage dividers sending a control voltage to 5 inputs on the TAPLFO chip. That means that to switch the pots around, we really only need to switch the wiper connections. If this was a more conventional analog circuit, you'd usually need to switch two or three contacts per pot and this simple wiring would not be possible.
EDIT! It just occurred to me that for safety's sake you should probably put a 1k resistor between 5v and the ring connection on the expression pedal. Otherwise when plugging the expression in you'll short 5v and ground for a second.
Quote from: Taylor on August 12, 2015, 05:34:26 PM
http://imgur.com/9Jwbotb
I believe this should do it for you. I couldn't think of a way to do it with just a DPDT switch as in your drawing. Maybe somebody else can think of a more clever way that uses only two poles, but the solution drawn here needs three - one to switch the tempo control input between the pot and the exp., one for the depth, and one to connect either the tempo or depth pot's wiper to the switch on the jack.
Note that I've drawn the toggle switch with the lugs oriented the way they are on a real switch, so the switch drawn toggles up and down. Might be confusing because the lugs are drawn the other way on your drawing, so it might look like I've turned the switch sideways (and it's harder to read orientation on the 3PDT because of the rotational symmetry).
This is simpler than with most pedals because of the rare fact that this pedal's controls are all just voltage dividers sending a control voltage to 5 inputs on the TAPLFO chip. That means that to switch the pots around, we really only need to switch the wiper connections. If this was a more conventional analog circuit, you'd usually need to switch two or three contacts per pot and this simple wiring would not be possible.
EDIT! It just occurred to me that for safety's sake you should probably put a 1k resistor between 5v and the ring connection on the expression pedal. Otherwise when plugging the expression in you'll short 5v and ground for a second.
This helps tremendously. I genuinely appreciate it. I'll update once everything's finished.
Quote from: Johnny B on March 08, 2012, 11:41:12 AM
I finished my tap tempo build the weekend before last and am still discovering all the things I can do with it. I had no problem with the build other than that I had a dud NSL-32 which I had to replace. I used a 1590BB and with 6 pots, 3 switches and an external tap input. It fitted perfectly. Here are a few pictures of the pedal
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0059Small.jpg)
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0060Small.jpg)
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0064Small.jpg)
(http://i1207.photobucket.com/albums/bb462/jballett/Tap%20tempo%20tremolo/DSC_0065Small.jpg)
Was your LED working before you replaced it? I'm considering just replacing it as I've tested just about everything else in my build but was wondering if I'm having the same issue you had
Sorry for the the 4 year comment gap ;D
Hello everyone, first post here and had some questions on the TTT if anyone can help me out id appreciate it. So I bought this board a couple years back to build for a friend. He ended up not wanting it so it sat on the shelf until I saw a demo of one and decided I would like to have it. I started putting it together and testing it with what I thought were issues but I am not entirely sure if it's in my head. After hearing audio samples and hearing that this is a full deep sounding tremolo I was thinking I might have problems because mine does not seem all that deep trem described or that I have herd. At first I though I had no trem and my signal was just being manipulated from the tap circuit so ill explain...
Here is what I have.
1: Have audio bypassed and engendered.
2: I am getting some modulation and the LED is functioning and reacting to the LFO and both the trim pots.
3: Both tap and EXP switches affect the signal and all of the pots have some noticeable effect to the circuit and it seems (Still on test rig) that It does cycle through most or all of the waveforms.
4: Also, I externally mounted the gain pot and that is more than obviously working...almost too much (seems that pot needs a smaller value). SO, all that being said it would appear (even to me) that the circuit is working right? However after hearing several more samples, I still don't seem to get the smooth depth tremolo that others are. This is why I wonder if it's all in my head as I'm not familiar with a digitally controlled signal. So in an attempt to not drag out a post for days and before I start digging into It, I decided to test things and provide in detail, in a single post what I do and don't have in case anyone has any advice at all.
So now that you know what I have, here is what I (for sure) have noticeable problems with. .....
1: My tap tempo switch seems to have an odd lag issue which I assume can be normal given its function. At times I barley tap it and it changes tempo, sometimes I have to hold it down for a bit to get it to change, sometimes it works as described and cycles through every tempo and sometimes only one or two.
2: My biggest thought that there might be a problem is the fact that in all the posts I have read I have noticed that almost everyone does (and seems to love ) the wave distort function described in the BOM but My Wave distort Seems to do Almost nothing at all no matter what wave form I am in. IN fact, the only thing I hear at all is just when I am sweeping the pot back and forth but otherwise nothing all the way up or down.
Because of this I decided to poke around because I do have an issue if that's not working and wonder if it's related to my week trem. I did all the standard, looking for and reflowing cold solders, traces, testing voltages etc and the pic below sort of details what I have found so I am hoping someone can point me in some direction of what to look for.
(http://s20.postimg.org/ms8178rtp/tap_temp_voltages.jpg)
So in this pic the RED trace is reading all 9 volts up to the Vreg where it hits 4.5 volts and all the orange test points and orange dots are reading 4.5-5 volts so that's good. In addition to that all of the Green dots are reading 0 as I think they should. Also for reference I tested voltages on both IC's as shown below but they seem good to me
TL072
Pin 1=4.69
Pin2=4.67
Pin3=4.66
Pin4=0
Pin5=4.64
Pin6=4.68
Pin7=4.7
Pin8=9.39
PIC
Pin1=4.99
pin2=2.06
pin3=2.04
pin4=4.48
pin5=0-2.8
pin 6=.002
pin7=0-3
pin8=4.48
pin9=.728
pin10=4.98
pin11=3.11
pin12=1.21
pin 13=2.93
pin14=.001
Pin 5/7 change with led pulse. The led got brighter on when I touched pin 9 and when I touched pin10 the tempo or multiplier seemed to change if that means anything.
I know that I get audio from in to out but just to eliminate any variables decided to trace the trem circuit out and probe it at each test point as seen in this picture.
(http://s20.postimg.org/ikd8yhqe5/tap_tempo_help_audio_path.jpg)
So from the test points in my pic I get a clean signal from points 1-4 but nothing after the 220k resistor nor on test point 5 (pin to of the IC) I get clean signal back on test point 6 and 7 (pin one of the IC) and clean signal on test point 8. I get no audio from point 9 where I would think I should start hearing the tremolo right? Because after that from point 10-ouput I get a tremolo effect. (also get trem effect on pin 7 of the IC). Shouldn't I get audio from point 5 and trem from point 9? I am hoping for any info if anyone can help. I am using an nsl-32 and have a spare and VTCL-3's I think but unknown if changing is necessary or will help and don't want to if I don't need to. I already had to swap the 3904 and unfortunately pulled the solder pads right off this board and that sucked. I was kind of disappointed with that because this bored looked well made and I know I did it the right way. I spend all day at my day job fixing and re-certifying %^&*pit equipment for the FAA so I literally do solder rework everyday and have all the right tools..O well not the biggest deal just scared to do anymore then I have to. Anyway sorry for the long post if anyone sees anything wrong ...or nothing any thoughts or advice would be greatly appreciated. Maybe I just don't like the sound of the circuit? Who knows
revolvercustoms, i can't get at my board. It's in a rack. But I will say, this is a very robust effect and if you think it"s not working the way it should you are probably right. I always step back at the point you are at and double check parts and values everywhere. So far I have never found that I didn't have a cold solder or broken trace or misplaced part in a circuit board I bought. I have never bought a malfunctioning board. Did you buy the pic with the board or from someone else? Look at the circuit diagram and audiotrace the signal path AFTER you are sure all the components are correct. Scrub the xtra flux off, etc. Also, if you have the switch wired in, remove it so you just have the board with input and output. Good luck and I hope someone more clever than I chimes in. Joe.
Quote from: revolvercustoms on February 07, 2016, 06:51:22 PM
1: My tap tempo switch seems to have an odd lag issue which I assume can be normal given its function. At times I barley tap it and it changes tempo, sometimes I have to hold it down for a bit to get it to change, sometimes it works as described and cycles through every tempo and sometimes only one or two.
You mention you work on electronics for a living so apologies if I'm telling you things you already know. :)
It sounds like your switch contacts are bouncing, so fast double-taps in the switch mechanism are sending bad timing info to the TAPLFO chip. What type of tap switch are you using? The MCU has debouncing in the firmware, but it may not be enough if the switch is bouncing a lot. You can add some hardware debouncing, as shown here (http://www.ganssle.com/debouncing-pt2.htm).
Quote2: My biggest thought that there might be a problem is the fact that in all the posts I have read I have noticed that almost everyone does (and seems to love ) the wave distort function described in the BOM but My Wave distort Seems to do Almost nothing at all no matter what wave form I am in. IN fact, the only thing I hear at all is just when I am sweeping the pot back and forth but otherwise nothing all the way up or down.
Do you by any chance have resistors installed in the spots to which the Wave Distort wires are soldered? You need to not fill those two resistors when the Wave Distort pot is used, as shown in the build docs.
QuoteSo from the test points in my pic I get a clean signal from points 1-4 but nothing after the 220k resistor nor on test point 5 (pin to of the IC) I get clean signal back on test point 6 and 7 (pin one of the IC) and clean signal on test point 8. I get no audio from point 9 where I would think I should start hearing the tremolo right? Because after that from point 10-ouput I get a tremolo effect. (also get trem effect on pin 7 of the IC). Shouldn't I get audio from point 5 and trem from point 9? I am hoping for any info if anyone can help. I am using an nsl-32 and have a spare and VTCL-3's I think but unknown if changing is necessary or will help and don't want to if I don't need to. I already had to swap the 3904 and unfortunately pulled the solder pads right off this board and that sucked. I was kind of disappointed with that because this bored looked well made and I know I did it the right way. I spend all day at my day job fixing and re-certifying %^&*pit equipment for the FAA so I literally do solder rework everyday and have all the right tools..O well not the biggest deal just scared to do anymore then I have to. Anyway sorry for the long post if anyone sees anything wrong ...or nothing any thoughts or advice would be greatly appreciated. Maybe I just don't like the sound of the circuit? Who knows
Not all points in a circuit are amenable to audio probing, so for example your point 5 (pin2 of the TL072) is in this circuit a "virtual ground (https://en.wikipedia.org/wiki/Virtual_ground)," so it's normal that you'd hear no signal there. The same is true for your point 9, because it connects to the inverting input of the next gain stage and is again a virtual ground. So there's nothing out of place there.
What do you hear at pin 7 of the TL072? That's the output of the second stage.
To address your depth problem, first, just to be sure, you've experimented with different settings of the Depth control, and you do get noticeable change in depth, but just not a huge change?
How does turning the trimpots affect the depth of your tremming? At all?
Apart from the amount of volume modulation("depth"), is the audio sound itself weak and noisy or pretty normal?
Thanks for the response Taylor, I figured it was a timing issue with a switch. That is an interesting read on debouncing and I will look into that at a later point. The switch I am using is a soft touch normally open momentary. To be Exact here is the link to the part.
http://www.conrad.com/ce/en/product/701083/Pushbutton-250-Vac-3-A-1-x-OffOn-SCI-momentary-1-pcs
As far as the wave distort here is a pic of how I have it wired and from day one I left the 10k's out.
(http://s20.postimg.org/4wl4wbba5/wave_destort_wiring.jpg)
I did test the pot last night and it is working as it should and did test for continuity between each lug on the pot to the solder points on the back of the board and all checked out there as well, Just an fyi...still does nothing at all and I have no reference to what it should do...lol
Now as for the audio path I did look at it little more last night and noticed the virtual ground so my apologize for missing that, that's a my bad so everything there seems to check out ok then. On PIN 7 of the opamp I am getting a trem affected signal when probed as well as from test point 10 all the way to the output.
Now, as far as the depth of the tremolo I noticed that I didn't do a great job explaining that so I'll try to explain it a little easier. Aside from the "wave distort" having no function I think the rest of the controls and the circuit for that matter are doing their job and seem to at least function as intended because I get a noticeable change in the effect when I use them. However, you asked if the trimpots had an effect on the trem itself and would say not really. one I notice just seems to turn the led on/off and the other seems to control the strength of the rate led and seems to increase ticking, noise and ads a bit of gain.
The point I was trying to make of the tremolo sounding week could be explained better so I will use a better example. I of all people should know you can't always trust an audio sample when comparing things but again it's my only reference. So to explain my issue audibly let's just say for example that this pedal is a Univibe. In all the samples I have listened to it seems like everyone has a full functioning univibe and mine though it works, sounds as if it has no light shield if that helps. I am getting a tremolo effect but I am not getting the Phasing depth that I hear out of others who built this. It's almost like light is escaping from my opto which it's not (at least visibly anyway) or there is too much resistance on it or not enough input current to the LED side of it. Hopefully that makes more sense to you. I guess I was just curious if there is anywhere in the circuit that I could look at that might be suspect to this type of issue before giving up on it or replacing un necessary parts.
I did have a question related to the opto though, I was trying to see if I couldn't get the phase depth figured out (or just wanted more) if there was any mod I could come up with to increase the input current on the LED side in hopes to increase phase depth (i know this is the function of the trimmers but they have little affect.) I assumed this was thought of when the circuit was designed but was curious why the Nsl-32 was chosen. Of course I bought and used a couple as the BOM recommended them. Just curious because I had some VTL5c3's lying around and never used a NSL-32. Aside from them being cheaper than the VTL I looked at the datasheets and they appear to be damn near identical. However, I did notice that the response time of the VTL5c3 was much faster than the NSL. Granted the difference in turn on time is marginal and likely impossible to notice, I did notice the decay time is almost 5 times as fast. Was wondering if the faster response times would help with ticking and add any noticeable depth, especially in the square wave and random settings? Have you tried one at all and notice anything or in this type of application would it even make a difference enough to notice? Just curious...Damn! I just nerded out, I need to go have beer and man up a bit...lol thanks for all the help folks.
Quote from: revolvercustoms on February 08, 2016, 08:24:14 PM
As far as the wave distort...still does nothing at all and I have no reference to what it should do...lol
The wave distort functions like pulse width modulation, but for all waveforms. You can hear it (on a working build) most easily on the square wave. With wave distort centered, the square wave will have 50% duty cycle - equal time on and off. Turning the knob one way will narrow the pulse width so it's on less than half the time - as you decrease it all the way the square wave will just be a very short blip and mostly off. Once the audio section is working, you'll be able to hear it better and you may find that it actually already is working, since it seems your entire digital portion (the TAPLFO and surrounding bits) is probably working as it should.
Quoteyou asked if the trimpots had an effect on the trem itself and would say not really. one I notice just seems to turn the led on/off and the other seems to control the strength of the rate led and seems to increase ticking, noise and ads a bit of gain.
That's what they should do, and if you haven't tried to "tune" them, that's definitely going to give you the depth problem. Again if we think only of a square wave (hard on/off, for simplicity), the "off" volume is basically fixed by the dark resistance of the optocoupler. In between the chips, the trimpot on the right (the one you said increased ticking, noise, and gain) effectively controls the "on" volume, and you want this to be as large a difference from the off volume as you can make it without bad ticking. While you're tuning these to get the best response, I recommend you turn down your gain pot or it will make the noise and ticking you might be getting worse. Make sure your wires to the gain pot are not routed physically near the digital part of the circuit or ticking could get capacitively coupled into the output gain stage.
QuoteI did have a question related to the opto though, I was trying to see if I couldn't get the phase depth figured out (or just wanted more) if there was any mod I could come up with to increase the input current on the LED side in hopes to increase phase depth (i know this is the function of the trimmers but they have little affect.) I assumed this was thought of when the circuit was designed but was curious why the Nsl-32 was chosen. Of course I bought and used a couple as the BOM recommended them. Just curious because I had some VTL5c3's lying around and never used a NSL-32. Aside from them being cheaper than the VTL I looked at the datasheets and they appear to be damn near identical. However, I did notice that the response time of the VTL5c3 was much faster than the NSL. Granted the difference in turn on time is marginal and likely impossible to notice, I did notice the decay time is almost 5 times as fast. Was wondering if the faster response times would help with ticking and add any noticeable depth, especially in the square wave and random settings? Have you tried one at all and notice anything or in this type of application would it even make a difference enough to notice? Just curious...Damn! I just nerded out, I need to go have beer and man up a bit...lol thanks for all the help folks.
I think the NSL-32 was chosen originally because it was cheaper and easier to find than the vactrols, especially outside the US, at least in 2010 when the project was created. The 5c3 is probably better in terms of its on and off resistances, which here we want to be quite low and quite high, respectively. The faster response would also mean more accurate LFO waveforms, and more depth at high speeds, although hypothetically might be more likely to tick since the circuit is relying entirely on the slow response of the optocoupler to filter the PWM signal coming out of the TAPLFO into an analog LFO waveform.
Currently working on this project. Anyone have any oscillation issues when the supply voltage goes below 9v?
Also, how is the noise? My layout seems to add a reasonable amount of hiss and some "thumping" on high depth settings.
It sounds like you may need to do more tweaking on the trimpots. Lots of noise might indicate you have the gain trim turned up very high, possibly to compensate for not enough current going to the optocoupler LED. Try setting the opto trim higher, and the visible LED and gain trims lower.
Forgive this post but I am feeling really stupid today sorry. So I had this board for a bit but never finished it until a bit ago and before boxing it up I ended up robbing the waveform pot cause I was in need of a 10k pcb mount pot. Anyways, the problem is I wanted to use a rotary switch in its place but couldn't check the voltages as I took the pot. For some reason my computer will not open the Tap lfo datasheet so I'm now confused. I saw another user posted a gut shot of how they did it and from what I could gather from the photo it would appear that the resistors are wired in series from 5k-10k-5k etc. so my assumption is each wave shape is fairly evenly stepping down the control voltage which looks to be pin 12 of the IC, is this correct? I am still making a guess to this based on hard to see pictures but made this little diagram in the picture if anyone can confirm or advice me otherwise if this is right or wrong that would be kick ass and much appreciated. Also, I have never attempted to use switching instead of a POT but if this is wired correctly the 3.6k (R8) would stay in its place right, or is that removed? Thanks
(http://s20.postimg.org/7ee98q1ul/ROTARY_POT_WAVEFORM_2.jpg)
What you have there is right, except that your switch positions 1 and 10 should not be connecting to the switch - those ends of the 5k resistors should only connect to ground (right pot pad) and 5v (left pot pad). So there should only be 8 positions on the rotary switch.
The 3k6 resistor is connected to the multiplier pot only, so leave it there unless you were going to replace the multiplier pot with a rotary switch as well.
Thanks for the response, i was questioning that. so is this updated picture wired correctly now? Am i also to assume that the switching would be in this order on the switch?
1. Ramp up
2. Ramp Down
3. Square
4. Triangle
5. Sine
6. Sweep
7. Lumps
8. Random
(http://s20.postimg.org/zakeidrdp/ROTARY_POT_WAVEFORM_2.jpg)
Also, im guessing i cant get away with this but ill ask. Little did i know i am out of 10ks at the moment I remember there being a fair amount of pot travel before the waveform changed shape so i assume the 10ks need not be perfect tolerance. I have a Crap load of 9.1ks so if i were to use them in place of the 10ks and thus adjust both 5ks to compensate for the difference in value could i get away with that or would i be running into problems some where in the chain?
thanks again.
Quote from: Goosefeathers on April 08, 2016, 07:39:14 PM
Thanks for the response, i was questioning that. so is this updated picture wired correctly now? Am i also to assume that the switching would be in this order on the switch?
1. Ramp up
2. Ramp Down
3. Square
4. Triangle
5. Sine
6. Sweep
7. Lumps
8. Random
Your new drawing looks right, and that should be the order (make sure to move all the resistors down one position so the first throw on the rotary switch connects to the 5k-10k node, etc.)
Quote
Also, im guessing i cant get away with this but ill ask. Little did i know i am out of 10ks at the moment I remember there being a fair amount of pot travel before the waveform changed shape so i assume the 10ks need not be perfect tolerance. I have a Crap load of 9.1ks so if i were to use them in place of the 10ks and thus adjust both 5ks to compensate for the difference in value could i get away with that or would i be running into problems some where in the chain?
thanks again.
If you scaled the 5ks down by the same amount, it would work just fine. But, you'd need something around a 4.5k resistor, which most people are unlikely to have lying around.
This circuit is not picky about overall resistance - notice that you can use either a 10k pot or a chain of resistors on your rotary switch which total 80k, and it works the same either way. So a 10% change in either direction won't matter as far as the total resistance, but you need to keep the ratios about the same. If the ratios were too far off, your switch might give you the same wave at two positions and be missing one of the waves. But, honestly it would probably be fine with 9.1k and 5k values. If you find that the switching doesn't line up right you can always add a larger resistor in parallel to get the value down to 4.5k or so.
There are online calculators (http://www.sengpielaudio.com/calculator-paralresist.htm) for lazy people like me. :icon_wink:
Thanks again. Lazy??? I know all about that, i knew i had the poles wrong on the rotary switch but we both get it, i was just to lazy to redo the graphic. Also i know about resistor calculators too, Theres an app on my phone for that. :icon_biggrin: 4.5k is not in the average parts bin in this particular hobby i would assume but wouldn't think 5k would be either. Anyways, that's what my (or my phones app) calculated as well but got some 4.3ks that should work. if not i also have a bunch of broken stuff littered with 10ks and a few yards of solder wick so will make it happen...then again...lazy. lol I assume you're the one who produced this fun project? if so nice job.
Thanks, glad you like it. Yep, I designed the board and ship them out and all that. The TAPLFO chip was created by Tom Wiltshire (http://electricdruid.net/product/taplfo-tap-tempo-lfo/) and a few others mentioned in the build doc also contributed, so I don't want to take all the credit.
I'm having a problem with my build. It makes a loud beeping noise like a fire alarm. I can get it to go away but only by turning down the gain and thus the guitar. The tremolo does work but the beep is at least twice as loud as the guitar. Is there likely a faulty component causing this? I'm a bit lost where to start. No combination of trim pot settings removes the problem. The beep is present on bypass too.
Thanks in advance.
Hmm... that's a perplexing one. Could you post a video of what it's doing?
There's no audio source in the circuit. Technically, the PWM signal coming out of the TAPLFO chip is an oscillator with a frequency of ~20kHz. Most people can't hear that high (especially musicians due to hearing damage) and even if you could, it wouldn't sound like a beep, so much as that barely perceptible sound of being in a room with an old CRT television.
Thinking outside of the box here, maybe if you used the wrong crystal (one with a lower resonant frequency) the PWM would also come out at a lower frequency. It would turn from a continuous tone into a periodic beep if it's getting into the audio path and going through the tremolo.
But, that all seems unlikely to me especially if you're sure you used the right crystal. Since you mention it's there in bypass, and the effect is true bypass, maybe something that's supposed to be grounded is not, and that's causing hum to get into the tremolo. Can you post a photo of your wiring?
Quote from: joe_t on May 20, 2016, 07:20:07 AM
I'm having a problem with my build. It makes a loud beeping noise like a fire alarm. I can get it to go away but only by turning down the gain and thus the guitar. The tremolo does work but the beep is at least twice as loud as the guitar. Is there likely a faulty component causing this? I'm a bit lost where to start. No combination of trim pot settings removes the problem. The beep is present on bypass too.
Thanks in advance.
If the beep is present on bypass too, what makes you think it's coming from the circuit? The circuit wouldn't be able to produce any output if it's bypassed. Or maybe there's something up with the bypass switch wiring?
Thanks,
Tom
Hello, this pedal interest me a loot, but i am a total noob at this. I only modified my CryBaby yet following things on internet... Is there any way to get a pcb with all components mounted already? and what would be the price? :3 i really would like to do it myself, but seeing a lot of peoples burning things here, i am scared to give it a try...
I am not really at ease with schematics... maybe someone could make a noob-friendly "tuto", by that i mean just post pictures of the pcb with all components mounted, and legends, so telling where are going wires to etc.
It would be awesome and would probably decide me to give it a try myself, and be proud of the result while using it on stage ^^
I don't sell the boards pre-populated, but if you make a post in the For Sale/Trade section (http://www.diystompboxes.com/smfforum/index.php?board=7.0), somebody may be up to do a partial build for you.
You don't really need to be able to read schematics to build this, though. The build document (which you can view here (http://www.musicpcb.com/documentation/))tells you where the wires go and which parts to buy, and each part is labeled directly on the board. There are lots of photos of built PCBs in this thread, to give some visual context.
It's not the best beginner project, though. If I could give advice to myself when I was first starting with DIY electronics, I'd say to start smaller and get some simple builds fully completed and working, before trying to make the really cool complicated thing I actually wanted. Instead, my first build was so annoying that it took me 5 more years to try building a pedal again. I don't think there's anything wrong with buying a kit. Also consider checking out some of Madbean's projects (http://www.madbeanpedals.com/projects/index.html) with only one or two knobs.
thank you!
Can't find the answer in this thread ? On the build docs it states 3x22k trim pots but on the prefab I have just received they are marked as 10k what should I be using?
Also before I mount switches the spst for the tap has anyone got any recommendations for supplier as the tayda ones I have have a click to them prob nothing but didn't know if people used any that were smooth/quieter.
Thanks
I have used these ones:
http://smallbear-electronics.mybigcommerce.com/momentary-spst-no-soft-touch/
I see you're in the UK so I'm not sure if Small Bear is a viable option for you.
For the trimpots, go with 22k if you haven't already purchased them. That gives you more leeway for tweaking in case you run into ticking with your build.
Cool I have 22k trim pots I'll use them, I'd have to have a reasonable order to use small bear and even then with postage it wouldn't be that cheap,
Can someone double check this before I do it wrong when fitting the pots to the underside as pics which way does the one that I swapped round go and have I got the others right
Don't want to do all legs to realise it's wrong :icon_redface:
https://www.flickr.com/photos/141176322@N02/shares/o221Zh
You've got the top row of pots right. The depth pot should go underneath the board, like the first photo.
Hey Everyone,
Just finished putting this thing together. The LFO & LED seem to be working and the Depth,Tempo, Waveform, And Multiplier pots seems to work as well. I'm not getting any sound. I've searched through about 22 of the 48 pages on this thread and tried setting all 3 internal trims to the middle including the wave distort pot. Still nothing. I've attached a link below with a photo of the PCB.
Please note that I have not done the off board wiring as I use a little test box to hook everything up to limit possibilities during troubleshooting.
I also wiring the NSL-32 on the backside of the pcb. Long leads on the resistor side. The white dot is on the trim pot side on the pad that isn't marked with "+"
Thanks in advance!
https://postimg.org/image/t9h06apjl/
With an audio probe (http://www.diystompboxes.com/wiki/index.php?title=Debugging), check if you have audio at pin 1 of the TL072 (first opamp output), and if so, then check pin 7 (second opamp output). That'll narrow down the issue to before or after (including) the optocoupler.
Also, make sure you've got the wave distort knob centered while testing. It's possible to get silence with certain settings otherwise, which would make debugging more annoying.
Thanks for the quick response. I'm getting signal from Input to Pin1 of the TL072. I am also getting signal from Pin7 of the TL072 to the output. I'm guessing it's something to do with the NSL-32. Wave Distort is set to center position. Solder connects look fine but I'll do some reflowing if anything looks shady. I'll order a new one and let you know.
That indeed was the problem. This thing is excellent. Thankyou!
Glad you got it sorted - happy tremming!
I know this is a straight forward problem but can't won't out the best way to fix the build doc page 7 shows how to wire the 3pdt to include the visible led (tap tempo) but no on/off led for bypass/effect I thought I could go from dc plug +ve to clr to led to ground but there isn't a ground Conection on the 3pdt that is made when the effect is on? Or have I missed something
The way the switch is drawn on page 7 of the docs the visible tap tempo led is turned off when the effect is bypassed and flashes when the effect is on, so you don't need a separate bypass/effect led.
If you wanted to you could wire the tap tempo led straight to LED pos and neg on the board and it would flash all the time, you could then add a separate bypass/effect led to the 3pdt. This means you can see the tempo when the effect is bypassed if that's useful.
That would work I wanted the bypass led for the artwork design as much as anything. So does that mean the tap led will flash all the time when dc is plugged so could be used as a tap tempo without any effect being on (essentially a led silent metronome) as that might be useful anyway :)
Yeah, the tap led will flash if power is on.
Right fired this up for the first time, no audio :( so far checked pin 1 TL072 and I got it there but nothing on pin 7 does that mean it's the Opto ?
Probably so, if your flashing LED is flashing. If the LED is also not flashing, then the digital side is not working yet.
No flashing led either, the only time it has flashed is if I touch I think pin 3? I think On taplfo with my DMM
If I touch it comes on hold it against it flashes?
OK, maybe the next step would be to measure the voltage at each pin of the TAPLFO chip and also the 78L05 and post them here. It's usually easier to get the LFO working first, then the audio section.
I'll measure all the pins in the morning, does it matter what position the pots are in?
Not for measuring voltages, but I'd just set them all in the middle while debugging.
1- 4.93
2- 2.03 *
3- 2.34
4- 4.93
5- 0 (4.91*)
6- 0
7- 0
8- 4.93
9- 1.88
10- 0
11- 0.68
12- o
13- 0 (1.52*)
14- 0
1- 4.49
2- 4.49
3- 4.46
4- 0
5- 0 (4.49*)
6- 0 (4.49*)
7- 0 (4.49*)
8- 8.99
2 when I touch this with the dmm it makes the led flash if led is off voltages non brackets if touch pin and led is on voltages in brackets
Pin 2 of the taplfo chip is one of the pins that goes to the crystal, if there's a problem round there the chip won't run which is why the LED isn't flashing. If touching it with your DMM makes it work then you might have a dodgy connection to the crystal, I would check and reflow the solder joints to pins 2 and 3 and the crystal and the two 22pF caps. If that doesn't solve the problem then make sure you haven't got any solder blobs shorting out those pins and clean off any flux, if it still doesn't work you could try making one or both of the 22pF caps a bit bigger, sometimes the crystal might need bigger caps.
I'm planning to implement the switchable expression pedal input for depth and speed as shown in this scribble by Taylor:
(http://i.imgur.com/id8BlAy.png)
1.) Where would be a good point to take the +5V for the TRS jack?
2.) "TS" in the picture refers to "Tip-Switch", right?
Thanks!
For the record, I have some ticking on this build too... Raising the 330p Cap to 1n didn't do much. After careful adjustment, I can get it to a point where it only occurs on the ramp up and square wave, and only when there is signal (i.e. when you turn your guitar volume knob all the way down it doesn't tick), but it's still noticeable to a degree where it's annoying. Could replacing C13 with a giant 470uf cap help? Higher gain transistor for the LED in the vactrol? I'll probably have to try different vactrols too I guess...
1. The leftmost pad for the Tempo pot is connected to 5v, so that might be an easy spot to solder to.
2. That's right - I think when I drew that it was referencing a particular jack somebody was going to use, so the drawing made more sense when looking at the photo for the jack.
C13 is bypassing the reference voltage for the opamps. It might be more useful to add another larger bypass cap between 5v and ground (leave C15 in place and add a larger one in parallel), since the LED and opto are pulling from the 5v rail, and the ticking is more likely IMHO coming from that sudden onrush of current on the vertical segments of the square and ramp waves.
I'm revisiting this after some time to update with my build. I'm having the same issue that someone had earlier with the fact that nearly every feature works except for the fact that no audio is present when the effect is engaged. The LFO indicator monitors modulation speed accurately, all of the knobs (even the rotary for waveform) work perfectly.
When bypassed, there is no ticking and my guitar plays through smoothly. As soon as the effect is engaged, the audio is lost except for some low-volume ticking when Ramp Up/Down and Square waves are chosen. I will also say that IC - 2N3904 is the only component that becomes rather hot to the touch, even after switching out between others. I've recently placed sockets where the 330pf capacitor would be to see if changing out the capacitor between different values would aid in some way. I've also switched between three different TL072 Op-amps.
It should also be noted that the trimpots don't do much of anything in the way of decreasing the ticking or affecting the LFO indicator's brightness in the slightest. Also, with the alternative wiring method, the LFO indicator does not activate. Only when I have both NEG and POS leads attached to the board does it function properly. I have no idea where to go from here.
Any help would be appreciated!
Sounds like there's something seriously wrong around the 2N3904. That shouldn't be getting hot.
If that's true, and there's a mistake there somewhere, that'll explain why there's no audio. Without that transistor turning the optocoupler on, you'll be stuck at permanently off.
HTH,
Tom
It's just strange that every feature is working properly outside of the audio. I'll check to see if I have an incorrect resistor or cap values somewhere perhaps. If that doesn't work, I'll order in a new NSL-32. If THAT doesn't seem to alleviate the issue, I'll just resort to seppuku.
Since you're saying all the knobs work but the audio path doesn't, the LED must be flashing, but you also said that the LED indicator doesn't activate. I'm sure that I just misunderstood part of that, but could you clarify what the LED is doing?
If you hear ticking but no guitar, that tells us that everything in the audio path after the optocoupler to the output is probably working. It could be a short/open somewhere between the input pad on the PCB and the opto.
But as Tom says, the 3904 heating up, and what you said about the trims seems to point to an issue with that transistor. You've probably already checked over all this, but make sure it's the right part number (and not, say, a 2n3906) and it's in the right way. Can you post voltages for all the pins of the transistor and ICs (including 78L05 regulator)?
I found the issue was a destroyed pad where the 100uf electrolytic was alongside the transistor. I was able to get it to work for just a brief moment and endowed the trimpots with the ability to adjust the LFO indicator, but it died shortly afterward and then the 10 Ohm resistor burnt to a crisp. I started this build when I was relatively new to being a DIY pedal enthusiast, so I'm going to purchase another PCB and try this again. With the new 3PDT boards I purchase for another build, everything should be pretty simple to adjust now that I have a bit more experience.
Thanks again guys.
Let me know if you happen to have some more boards shipped in so that I may order from the site.
The board might still be salvageable - if you post a photo I could give a suggestion on an alternate way to connect the parts with lifted pads. Sometimes it's easy to swing a component leg over to a via that the pad was connected to. But, the tap tempo trem boards are in stock if you wanted to start with a fresh one.
Here's one I haven't seen yet. Just built this one and like everyone else, I have some ticking. Been able to trim it out mostly. And it's only on the first three wave forms, however, it's there even when the effect is off. Most pronounced when it's off actually.
I'm not sure why it's passing through even when it's bypassed. My 3PDT switch is wired per the drawing build doc.
I suspect a grounding issue but not sure where it could be. The board ground is wired to the neg on the power jack and then to the sleeve of the input jack.
Any ideas?
Sent from my VS995 using Tapatalk
Here's the alternate version of the bypass wiring, which grounds the LFO signal while bypassed, should solve the ticking in bypass:
http://imgur.com/fi592fn
Quote from: Taylor on July 30, 2017, 03:01:33 PM
Here's the alternate version of the bypass wiring, which grounds the LFO signal while bypassed, should solve the ticking in bypass:
http://imgur.com/fi592fn
Yep. That worked like a champ. Thanks!!
Sent from my VS995 using Tapatalk
One more thing. I many have fried something.
I re-boxed it and while doing so, I made a couple of changes.
I socketed c15 so I could try different values. I inserted a 1uf to try first.
Also removed the wave distort knob and soldered in the resistors in its place.
I wired the led directly to the PCB, bypassing the switch so it's always on.
Lastly I added a status led.
When I first powered it on it worked for about 15 seconds then it just shut off. Took it back to my work bench and plugged it in and the resistor right next to the rectifier diode got red hot and burned out!
I replaced c15 with it's proper value and replaced the diode and resistor. Same thing happened. :(
Someone know what's causing that resistor to overheat? Where should I start looking? I already checked for shorts or solder bridges.
Sent from my VS995 using Tapatalk
Quote from: dafortier on August 12, 2017, 09:53:23 AM
One more thing. I many have fried something.
I re-boxed it and while doing so, I made a couple of changes.
I socketed c15 so I could try different values. I inserted a 1uf to try first.
Also removed the wave distort knob and soldered in the resistors in its place.
I wired the led directly to the PCB, bypassing the switch so it's always on.
Lastly I added a status led.
When I first powered it on it worked for about 15 seconds then it just shut off. Took it back to my work bench and plugged it in and the resistor right next to the rectifier diode got red hot and burned out!
I replaced c15 with it's proper value and replaced the diode and resistor. Same thing happened. :(
Someone know what's causing that resistor to overheat? Where should I start looking? I already checked for shorts or solder bridges.
Sent from my VS995 using Tapatalk
Nvmd.. I'm a dummy. Don't hook up a 12v power supply to a 9v circuit.
Can delete this and the previous post.
Sent from my VS995 using Tapatalk
Edit: ah, glad it worked out. :)
Original post:
If your status LED is taking power from the board, maybe try wiring it straight to the power jack instead. You could also try replacing the resistor that burnt out with one double the value - it has to do with filtering the power so changing this value won't affect the audio or LFO function.
Hey guys, did anyone encounter a problem where occasionally the pedal will lose volume when bypassed?
If you've wired it up as true bypass using a regular 3PDT switch, then you might have an intermittent wire/cold solder joint on your bypass switch or somewhere in the ground wiring off-board.
Hello, I am almost done w/this project (fingers crossed) and am thinking of boxing it w/board-mounted pots. I was wondering if anyone has a drill template designed for board mounted pots?
Hello!
Just curious, has anyone succeeded to swap taplfo2 to taplfo3 in this pedal? Not sure how it is possible. I would appreciate if anyone could share ideas :)
Information regarding updated chip can be found here: https://electricdruid.net/product/taplfo3/
Oo oo oo! I know this one! I know this one!! ;)
The TAPLFO3 can be used in the MusicPCB board without serious changes. One thing we aimed for when we did the new chip was to keep it compatible as far as possible. The differences are all listed on page 6 of the datasheet:
https://electricdruid.net/datasheets/TAPLFO3Datasheet.pdf
For the MusicPCB Tap Tempo Tremolo project the differences should boil down to:
1) Don't solder in the crystal or the two 22pF caps next to it. The new chip doesn't require a crystal.
2) Don't solder in the 10K on the tap tempo switch input (next to the 22pF caps you just ignored)
3) Don't solder in the 10K on the EXP switch input (furthest left of the three below where it says WAVE D|STORT). This is for the "Next Multiplier" switch, but this feature doesn't appear on the new chip.
That should get the PCB working with the new chip.
In addition, there are two new features:
1) If you add a SPST toggle switch between the two pads for the 22pF cap connected to pin 3 (e.g. pin3 connected to ground), you can select a new set of waveforms.
Incidentally, don't ground Pin 2 - it makes the pots work backwards! (This is actually helpful if you're using op-amp mixers to supply control voltages to the chip).
2) If you have problems with ticking, you can ground pin6. This activates the waveform smoothing filter giving all waveforms a 20msec rise/fall time. This should help reduce ticking noises.
I'd be interested to know how people get on with this - I haven't yet tried it myself, although I have a PCB around, so I could if I got my a$$ in gear.
HTH,
Tom
Just about to finish this one. I have a TAPLFO2d in it right now.
I can try the TAPLFO3c ....... I have a PIC 16F1824 I can burn the code on.
What would be the biggest advantage of going 3c over 2d (other then having more wave forms?)
I also have a midwayfair tap tempo Cardinal I need to finish. I'll keep the TAPLFO2d for that one.......maybe!
Quote from: alparent on September 07, 2018, 11:37:13 AM
Just about to finish this one. I have a TAPLFO2d in it right now.
I can try the TAPLFO3c ....... I have a PIC 16F1824 I can burn the code on.
What would be the biggest advantage of going 3c over 2d (other then having more wave forms?)
I also have a midwayfair tap tempo Cardinal I need to finish. I'll keep the TAPLFO2d for that one.......maybe!
Aside from "more waveforms", the biggest plusses for me are "less ticking" and "no crystal". The filtering should make getting a nice quiet tremolo much easier, even with the difficult waveforms like the ramps and the square. And the crystal is a part most people don't have lying about and it uses up two pins, so it had to go!
The frequency range, wave distortion, and multipliers and stuff is all unchanged, at least from a user's point of view. The waveform resolution and sample rate were improved too, but you probably won't hear that on a tremolo.
What I'm I suppose to do with all those PIC 16F684 now!?
Quote from: alparent on September 10, 2018, 09:39:35 AM
What I'm I suppose to do with all those PIC 16F684 now!?
(https://img0.etsystatic.com/175/0/14006236/il_340x270.1076044628_gyuy.jpg)
?? ;)
To bad they are not 16 pin! I could have sanded them down and sold them as SAD1024 on ebay.
Quote from: ElectricDruid on September 10, 2018, 11:29:14 AM
Quote from: alparent on September 10, 2018, 09:39:35 AM
What I'm I suppose to do with all those PIC 16F684 now!?
(https://img0.etsystatic.com/175/0/14006236/il_340x270.1076044628_gyuy.jpg)
?? ;)
I think we need to see a picture of you wearing these, Tom! ;D
Built this fine pedal today!! Version.3 ic. Subbed volume pot for the Switch mod for different wave forms, cool! Grounding pin 6 helped a lot with the different wave forms. Nice!
Welcome! And very glad to hear it worked well for you!
***Deleted because I'm a dumb.***
***Deleted because I'm a dumb.***
Finally it is done (PCB ordered in 2012).
Many thanks to ElectricDruid and Taylor for the help during the build, I had a lot of questions.
Mods:
- TAPLFO3 with Waveset and Smooth switched
- Center detent pot for the Offset knob (it's easy and I find it very useful)
- 4 inputs for the pots (except Waveform)
- Rotary switches for the Waveform and Multiplier
- PWM out, Clock out, Tap tempo in
(https://lh3.googleusercontent.com/pw/ACtC-3eqWUFFq5tMH1hhEPPLjlL8blE9iBAFkyYKHa2mVs3AzRlNIGEIFLNSbhLRXYvzGERhjQA_kcK2YaU7bDMUSSWafTqkAXRDSy4RKODZawUAODYts5VsLpVd-sZ2tU8DPnt8HIz2iEKbikWdYhnyL_7p=w1200-no?authuser=0)
(https://lh3.googleusercontent.com/pw/ACtC-3cN_QLxxCHs6oBed7gndUEjUC8ooGB_-_Dps3bNRs9oCI99VAQbX96AVefwunTaYZWqmYVIY1HDkKJqkSL6ld6WL4D2mXBO2X3rXPi4xdCQEgcUiqI8YZP_UJcCGu21wdsn64UMwxv38rCpuQshDYrA=w1200-no?authuser=0)
(https://lh3.googleusercontent.com/pw/ACtC-3dAwQa2b2YIUEjhEsrVrFNc68Rx-JrnpvJnnw1-afCX5BiPOMbucpyVtwM_Eo7lJAsK9PMpPwa1Rp4HUEvGxTtAkuYSfegkSOYTpHNPa9kSYEI5U4SUDXvERwnAwH-Dmhnp0GxuSLre6TFvc7ecrYIl=w1200-no?authuser=0)
Quote from: lespos on January 26, 2012, 02:21:42 AM
Quote from: Gaetano Capuano on January 20, 2012, 11:42:28 PM
CRAP where can I purchase an NSL-32 ???
http://www.smallbearelec.com/Detail.bok?no=356 (http://www.smallbearelec.com/Detail.bok?no=356) Small Bear Electronics is your best fiend ;)
There is my build
(https://lh5.googleusercontent.com/-DXz7I6fnJCE/TxCEKcu3G-I/AAAAAAAAAPM/yRHmLpEvsLQ/s640/P1130029.JPG)
For waveform and multiplier i using rotary switches instead of pots. That makes these functions a bit more understandabe. If someone interested - i found perfect rotary switches for that
http://eu.mouser.com/ProductDetail/ALPS/SRBV160803/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRYaNeyNyivdg%3d (http://eu.mouser.com/ProductDetail/ALPS/SRBV160803/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRYaNeyNyivdg%3d) 6 position for multiplier
http://eu.mouser.com/ProductDetail/ALPS/SRBV181004/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRbZTSllc6Pt4%3d (http://eu.mouser.com/ProductDetail/ALPS/SRBV181004/?qs=sGAEpiMZZMvNbjZ2WlReYusHPuglWmCRbZTSllc6Pt4%3d) 8 position for waveform
All you need to do is build additional PCB
There is PCB's (open with Sprint Layot)
with trough hole resistors (https://docs.google.com/leaf?id=0BxW0oyyuIeI7MjkwZTQ1YWEtMDVlNC00NmE2LWIxODgtYTA4NTczOWFlZmQ5&hl=en_US)
NOT VERIFIED because i build second one version with SMD (8060 size) resistors
with SMD (8060)resistors (https://docs.google.com/leaf?id=0BxW0oyyuIeI7NTRjZWY3YzYtNTVjOC00OWIxLTk1YTItM2Y3MTQ0NDA4NGI0&hl=en_US)
VERIFIED
all PCB's is ready to trasfer
Cool build! BTW, I'm curious, how the illumination like this is done?
I think it's one of these:
https://diystompboxes.com/zencart/index.php?main_page=product_info&cPath=3&products_id=87&zenid=9b5qciqnjrfv3d5d6ms3ad0hm4
https://www.diystompboxes.com/smfforum/index.php?topic=93606.0
Thanks! Will try.
Eurorack Tap Tremolo
• Eurorack 12HP: panel layout via FPD and toner transfer.
• PCB from Delek/Cherry Pie: https://www.delykpcb.com/product/cherry-pie-tremolo-pcb
• TAPLFO 3C, LFO Out and Sync In from Electric Druid: https://electricdruid.net/datasheets/TAPLFO3Datasheet.pdf
• 1P8T mini rotary switch (from alibaba, smallbear, adafruit, etc) with resistor string, for both Multiplier and Waveform/Shape, via Electric Druid
• True bypass relay from TH Custom: https://diy.thcustom.com/shop/uber-switch-relay-true-bypass-with-mute-kit/
• Homemade optocouplers using tayda photocells and superbrite yellow leds
• No ticking after removing C14 / added extra filter caps on voltage regulator outputs.
Still learning how all the controls interact together.
(https://i.postimg.cc/0rHvb4bn/IMG-3937.jpg) (https://postimg.cc/0rHvb4bn)
(https://i.postimg.cc/XXv3NW7X/IMG-3938.jpg) (https://postimg.cc/XXv3NW7X)
Quote from: dathey on May 13, 2021, 02:56:35 PM• No ticking after removing C14 / added extra filter caps on voltage regulator outputs.
Nice build!
Just curious what kind of filter caps have you used for voltage regulator outputs?
Just used regular electrolytic caps, 100uf or so, across both 5v regulator outputs. Can never have enough power supply filter caps...
(https://i.postimg.cc/hQTDgQ8G/Tap-Tremolo-ps.png) (https://postimg.cc/hQTDgQ8G)
So I recently pulled my Tap Tempo Tremolo back out, and while its always worked fairly well, I'm interested in the Taplfo 3 PIC. If I'm reading the data sheet correctly, I should be able to pull the crystal, the two 22pF caps, and R9 (pull up resistor).
Then I can ground pin 6 on the board (it doesn't look like its going anywhere), and use one of the pads from pin 3 to wire a switch to ground for the alt waveforms.
Does that sound about right?
(https://i.postimg.cc/4mN4kmwy/IMG-5195.jpg) (https://postimg.cc/4mN4kmwy)
Yes, that sounds about right!
The newer chip was designed to be compatible with the earlier one - just leave a few bits out.
Quote from: ElectricDruid on August 29, 2021, 12:56:22 PM
Yes, that sounds about right!
The newer chip was designed to be compatible with the earlier one - just leave a few bits out.
thanks!
My Tremolo started to behave in a strange manner. Sometimes it decides to slow down the speed 2-3 times, but returns to the original speed several seconds later. I was not able to define the circumstances when this was happening. I'm wondering if anyone had similar issue.
Haven't heard of that one, but my thought was maybe it has to do with the resistors on your multiplier switch. With parts tolerances, maybe one or two of them are off enough that the voltage produced is right on the boundary between two multiplier settings. Some stray noise or power supply fluctuation could be enough to click over the edge into the next value.
Sorry, I've not seen that before either. My first thought would be rather like Taylor's - bad pot maybe, leading to the value jumping?
One further possibility might be a unrelated CV going open circuit. The chip doesn't like have floating inputs and starts doing bizarre and often totally unrelated stuff when it happens.
Quote from: Taylor on August 12, 2015, 05:34:26 PMEDIT! It just occurred to me that for safety's sake you should probably put a 1k resistor between 5v and the ring connection on the expression pedal. Otherwise when plugging the expression in you'll short 5v and ground for a second.
I wired expression pedal inputs like this, with that 1k resistor, and I think that I was experimenting with expression inputs when speed knob crazyness happened. Probably, the best way to use the expression input is to make the connection when power is off to avoid any issues. Will also check whether my speed pot and multiplier switch are okay. Thanks for ideas guys!
Hi all, new here but very interested by this circuit, I expect I will be shot down for asking, but I'm really struggling to find the info. Are the PCB and Chip still available for purchase anywhere? the MusicPCB site just says that it's out of stock, is it no longer being produced?
Taylor can pop up and tell you about the PCB, but the chip is certainly available. The PCB was originally designed for the TAPLFO2 chip, but the current TAPLFO3 works too. Details here:
https://electricdruid.net/product/taplfo3/ (https://electricdruid.net/product/taplfo3/)
If the board's out of stock, I expect that's just the same supply chain issues that everyone's having. Things are taking ages at the moment, if you can get them at all.
I ran out of the last batch of boards and haven't ordered more yet. I was thinking of doing a redesign for the new chip, but just have too much stuff going on to start a new project at the moment. Also in the decade since this project originally came out, there are so many other pedal PCB guys now that I figured somebody was already selling an updated version.
Looks like a challenge for me... I'm really thinking to create a PCB for the updated version of the chip.
Welcome, Toad!
Thanks all, looks like time to buy a chip and start breadboarding!
Another taplfo-based (twin peaks) tremolo?:
https://pcbguitarmania.com/product/hattto/
https://pcbguitarmania.com/wp-content/uploads/2021/05/Hattto-Temporary-Building-Docs123.pdf
Appears both hi/lo pass cutoff frequencies are dip switch adjustable...
Got some more of these PCBs in stock for y'all. Here are ElectricDruid's instructions for using the newer chip on this board, if you'd like to:
1) Don't solder in the crystal or the two 22pF caps next to it. The new chip doesn't require a crystal.
2) Don't solder in the 10K on the tap tempo switch input (next to the 22pF caps you just ignored)
3) Don't solder in the 10K on the EXP switch input (furthest left of the three below where it says WAVE D|STORT). This is for the "Next Multiplier" switch, but this feature doesn't appear on the new chip.
In addition, there are two new features:
1) If you add a SPST toggle switch between the two pads for the 22pF cap connected to pin 3 (e.g. pin3 connected to ground), you can select a new set of waveforms.
2) If you have problems with ticking, you can ground pin6. This activates the waveform smoothing filter giving all waveforms a 20msec rise/fall time. This should help reduce ticking noises.