MN3007 ADA Flanger Clone Questions

[12Bass]

I thought that the idea was that you could control the amount of flange with your attack on the strings, say you pic gently and you get a clean tone strum the strings and you have flanging. sort of the thing one can do with a fuzz or or tube amp to controll dist. That was a brilliant idea I thought but if it doesent change that much It won't be worth the trouble. Since I never got mine to work I didn't have the opportunity to judge.   

Yes, it is possible to use the gate to dynamically control the flanging level.  Play over the threshold and the delay path gets added to the straight signal.  Maybe I'm just more of a "flange or no flange" sort of guy... 

[12Bass]

Added a pulsing LFO LED tonight.  

Instead of taking the feed for the power LED from +15 V, I hooked it up to terminal 3 of the Range control on the PCB via a 2 K resistor (this is the output of the LFO).  Now the LED pulses according to the LFO speed when the flanger is engaged.    Doesn't seem to be any problem with LFO ticking in the audio, but then I added some extra supply decoupling here and there....

[mean_dorris]

Shouldn't be. Where are you taking your clock f readings from?
What is your supply V at IC's 5&6?
And, which rev. board are you using? There are 2 spots designated C29 on the Moose PCB. Mare sure you have the cap in the correct one (the spot "in between" the ICs, next to R68).
Picture?

I'm taking my readings from TP. I managed to squeeze 170 kHz out with manual at 100%. That's pretty bad, I think. C29 seems to be in the right spot. I have 15 volts at 5+6 of the 4047.

Here are some pictures, I can try again if these aren't helpful. My camera isn't the best for macro..
Thanks again for your advice!

[oldschoolanalog]

Try this. Set the Range control so the LFO is disengaged. Set the Manual control full CCW. Take a V reading at IC3d, pin 14. Set the Manual control full CW. Take a V reading at the same spot (IC3d, pin 14).
Post results.

[mean_dorris]

With range at 0, manual CCW, I have 2.2V at pin 14.
With manual CW, I have 12.2V.

If I'm keeping my counter on TP, and fiddling with the manual knob and nothing else, should I be seeing a change in frequency? I've somehow been able to get 1.3mhz now with everything maxed, but it doesn't seem to want to stay anywhere near that value when I try to set the low point.

[oldschoolanalog]

With range at 0, manual CCW, I have 2.2V at pin 14. With manual CW, I have 12.2V.

OK, that's good . Your static CV is where it belongs.

If I'm keeping my counter on TP, and fiddling with the manual knob and nothing else, should I be seeing a change in frequency?

Yes. Absolutely.

I've somehow been able to get 1.3MHz now with everything maxed, but it doesn't seem to want to stay anywhere near that value when I try to set the low point.

The Clock High & Low trimmers are very interactive. 1.3MHz is what you want to see AT THE BBD. Maybe its time to adjust the timing components a bit (R68, R69, C29). Think you can carefully lift one end of C29 and tack on another 39pf cap in series with it & the board? (This will roughly 1/2 the cap value.) This will raise your max clock.
Remember: Carefully.
I'll try to find the math for those timing components. It's posted somewhere in the "mega A/DA thread", IIRC.
Try the cap thing first.
And, report back.

[mean_dorris]

OoOOoo Ok,

So I put a 33p in series with the 39p, as it was the closest I had. The manual knob has now become very interactive with the frequencies. Seems like the biggest obstacle now is that T5 doesn't really do a whole heck of a lot in either direction. I verified that it measures 100k. This is exciting... 
(Also I did that blinking LED mod. Very nifty thanks!)

[12Bass]

So I put a 33p in series with the 39p, as it was the closest I had. The manual knob has now become very interactive with the frequencies. Seems like the biggest obstacle now is that T5 doesn't really do a whole heck of a lot in either direction. I verified that it measures 100k. This is exciting... 
(Also I did that blinking LED mod. Very nifty thanks!)

Sounds like you're getting closer.  Are you hearing flanging now?  The effect of T5 is somewhat subtle.  It sets the range of clock frequencies (mostly the top end limit) and interacts with T4, so both may need to be adjusted to get things tuned properly.

Glad you liked the pulsing LED mod.  It's hypnotizing!   

[mean_dorris]

Yep, I'm hearing a flange, of sorts. I haven't plugged a guitar into it since I put in that extra cap, but it was doing a sort of flanging thing before, when the knobs were set just so. The manual knob and range knobs didn't really affect the sound much though, until they were maxed. Even the speed knob isn't all it can be. I think I might change to A500K instead of the reverse log. There aren't very many useful settings until most of the way through the sweep, then it gets mega touchy. And forget about threshold 

As far as measurements go, T5 is affecting the frequency by maybe 10% or less no matter where I've got things set. I feel like I could find a good balance if I could just get some performance out of that. Again though, I'm kind of shooting in the dark here.

[oldschoolanalog]

What value is R65 in your build? T5 should do alot more than you described. Also, it sounds like you might have the Speed pot wired backwards. Should be CCW=slow, CW=fast. If the range & manual knobs don't do much  there is a problem. First make sure it's biased correctly. Might be time to just recenter all the trimpots and do a complete recalibration as described in the pdf at Moosapotamus.
First recalibrate. Sounds like you're closer than you realize.
When I'm a bit more calm I will give my take on the threshold deal. Source of much unnecessary aggravation, grief and misunderstanding for me.

[mean_dorris]

Wow ok. Leaps and bounds here.
R65 turned out to be way too high. Swapped that out for the right value. I've been able to get 65ishk hz and 2.6ish mhz at TP, which I'm using because I can clip my counter onto a lead I've got soldered there.
I had a bunch of questions here but I've since solved them all. This thing sounds icredible. My only issue with it is still that speed pot, but I think I can just swap in an audio log pot and be fine.
Thank you big time for all of your help!!! I owe you a beer 

[12Bass]

My only issue with it is still that speed pot, but I think I can just swap in an audio log pot and be fine.

IIRC, the speed potentiometer should be reverse log, so a regular logarithmic (audio) pot is actually the opposite taper to what is specified, and "bunches up" the fast LFO range even more.  FWIW, I'm presently using a 100 K linear, which offers a workable solution - doesn't get super slow, but I wasn't using really slow sweeps anyway.  May order the reverse log some day....

[Valoosj]

Could somebody explain why R5 (1M at the input) is connected to Vb and not ground?
Or is this not a pulldown resistor to counteract popping noise?

[kurtlives]

Could somebody explain why R5 (1M at the input) is connected to Vb and not ground?
Or is this not a pulldown resistor to counteract popping noise?

Not a pull down,

Sets that op-amps bias (operating point).

[Valoosj]

Oh ok. I'll add a pulldown then. If I have some room to spare ...

[king take it]

just finished my rev5 board from charlie, great board btw kudos. i cant seem to calibrate it properly, with all knobs ccw i get good 25khtz but when i turn manual fully cw i could only squeeze out 770khtz max (measured at bbd pin2/6), i get nothing from the tp or from pin 13 of ic6 when checking hertz, i have 2 of every component cause i was gonna build 2 and have tried swapping ic's no luck. i have read the whole pdf and this entire thread, i have 150k in r65.  i checked voltages based on charlies or oldschoolanalog cant remember who posted earlier in this thread and mine are all within a few tenths of a volt except ic6 pin2/ic5 pin12 read good ccw .08v but cw where it should be 5v i have half of that 2.5v. also my t4 and t5 r very sketchy, i have adjusted in numerous positions on both trimpots and its always the same i hit 770khtz and then it starts to drop off rapidly, using either method at the end of the rev5 pdf. im on my lunch break at work now (measurements takin way to late into the night before) when i get home im was gonna try installing some single pin sockets i have for c29 and see a 10 or 20pf will work better any info would be great.  (also note set t1 and t2 using keyboard through fuzz face, and t3 and t6 50%)

[king take it]

also forgot to mention i do have flanging of sorts but its not very noticable at lower enhance settings but with it cranked i get a airplane flange take off effect, i have also tried all calibrations above with the same settings except with the threshold knob ccw and cw wasnt sure wich way was gating the effect, it may or may not be working not sure how strong my keyboard signal is, also have tried a guitar as well to check to see if it was working but its still only a flanging of sorts. also note i have tried both knob and trim pot settings as it is written in the rev5 pdf.

[king take it]

didnt get to change c29 yet, but i messed with the trim pots some more getting closer but still no luck, on my dmm i have 2 frequency options last night i tried using the dc option (square wave) and could not get any readings at all, so i used the ac option ( i figured it was this one anyway based on the pic of the o-scope) and thats where i got the 770khz but never got anythin at the test point.  i tried again on dc today and was able to dial a reading of 186khtz at best, but still got nothing at the tp. so i switched bak to ac and got the same htz as on dc but was able to get double those readings at the tp (wich as i understand from the thread is what it should be). getting a little frustrated so i probably wont switch out c29 till this weekend i need a break from it. also my input voltage from the 15v regulator is slightly under at 14.6v could that be my issue? i have a solid 9.2v measured at the charge pump in cant remember what is coming out but i checked it and it was close to 18v.

[king take it]

ok so i tried checking and resoldering some points of interest with no luck and rechecked my voltages and had some minor changes, most notably even less voltage at pin2 ic6/ pin12 ic5 so i decided to just recheck and record all voltages again and compare to thread with working flanger voltages and have some concerns so here is what i got

[king take it]

4007                                  4047                      mn3007                4049
1-x                              1-14.8 ~ 13.6             1-14.6                  1 & 16-14.9
2-x                              2-0.1 ~ 1.2                2-7.4                   2 through 7-7.4
3-0                              3-8.3 ~ 7.7                3-8.8                   8-0
4-x                              4-14.9                       4-1                      9 through 15-7.4
5-x                              5-14.9                       5-0                      13-x
6-0                              6-14.9                       6-7.4               
7-0                              7-0                           7-7.65 ~ 6.4
8-x                              8-0                           8-7.65 ~ 6.4
9-x                              9-0
10-7.1 ~ 4.75              10-7.4
11-8.3 ~ 7.7                11-7.4
12-0.1 ~ 1.2                12-0
13-x                            13-14.8 ~ 13.8
14-14.9                        14-14.9