Building the tap tempo tremolo

[stone temple pinot]

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

[therealfindo]

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

[Taylor]

Yes, the trimpot above the tl072 is the gain.

[Valoosj]

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.

[Taylor]

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.

[Valoosj]

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.

[Valoosj]

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 ...

[loki]

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?  

[slacker]

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.

[loki]

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!

[Brejna]

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 , 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

[9aul]

Hi, I've just finished building the taptempo but alas when I plug it in no signal from my guitar gets through  . 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.

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.

[threepwood]

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?




For reference (ignore the red circles)



Thanks in advance

[Ultrakd]

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?

[mth5044]

^ 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.

[Ultrakd]

^ 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?

[LaceSensor]

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?




For reference (ignore the red circles)



Thanks in advance

The glaringly obvious lack of trimpot?!

[bcalla]

I think he's doing the same mod I did - replacing the trimpot with an external pot.  The wires are on the bottom.

[lars-musik]

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.

[threepwood]

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!