SOLVED Sugarbag Overdrive no signal

[Fama]

First off, I apologize for the abomination of a build. I first put in the 2N5088 in the wrong orientation, clipped off the legs and tried desoldering for a bit, but it didn't work very well so I just soldered a new one on top. I also subbed two of the 1uF coupling caps (?) for 470nF due to lacking 1uF parts. And finally C100 is two 4.7nF caps instead of a 10nF cap.

So, I'm not getting any signal through. I tried audio probing, R1 is fine on one end, nothing on the other (since it's grounded, obviously), R2 is fine on one end, and very quiet, thin and distorted on the other end. I get the same thin, very distorted sound on pin 2 of IC1 and also on one side of R3. Nothing on any other pins of the TL072.

R2 seems to be the correct resistance, it measures as 390k. However, R1 measures at 0.04 ohms or so, while I think it should be measuring correctly if everything was ok? The bands match up with 10M that it's supposed to be. My DMM doesn't go higher than 2M, but it just shows 0.00 at max setting, and with the lowest resistance setting it shows 0.04-0.06 or so. Edit: I'm dumb, when the footswitch is on bypass, the PCB input is grounded, so of course R1 measures as zero. When I switch the footswitch it doesn't register anymore, which it should, as the DMM only goes to 2M like I said.

There are also a couple of scrapes on the underside of the board where the copper shows through which I was afraid might have ruined the board, but I don't think the signal should stop that early if that was the case.

 

[Fama]

C6 definately needs to be pulled as it's going to ground & he should be getting a reading!???

I switched C6 out, and it did give a correct reading (well, 23uF or so) once it was pulled. No change in any behaviour, so that wasn't the issue either - it was just an anomaly that it wasn't read correctly while on the board, I assume.

In my mind, the #1 issue here is that I get ~4.3V on pin 3 of IC1 (Vref), and I get a faint signal going into pin 2 of IC1, but I get nothing out of pin 1 of IC1. If I feed the opamp a signal and Vref to the inputs, and ground and Vcc match up, shouldn't I get something from pin 1?

 

[music6000]

I

I switched C6 out, and it did give a correct reading (well, 23uF or so) once it was pulled. No change in any behaviour, so that wasn't the issue either - it was just an anomaly that it wasn't read correctly while on the board, I assume.

In my mind, the #1 issue here is that I get ~4.3V on pin 3 of IC1 (Vref), and I get a faint signal going into pin 2 of IC1, but I get nothing out of pin 1 of IC1. If I feed the opamp a signal and Vref to the inputs, and ground and Vcc match up, shouldn't I get something from pin 1?

If you are not getting a buildup on the underside, The iron is too Cold or your not leaving it long enough.
Beng restricted to Unleaded Solder makes it more critical as it is needs more heat to flow!
I would reflow the Solder joints on all components, the solder on the resistors should look something like this below:

 

[Fama]

After doing a bunch of things, I got a decent sounding signal all the way to pin 7 of IC2, but not to R20. I then made a solder bridge from IC2 pin 7 to the same end of R20 where C11 connects to. Now I get a signal - but it feels like there's too much gain, it's basically a farty fuzz and the volume pot doesn't make any difference. But at least there's progress.

 

[music6000]

After doing a bunch of things, I got a decent sounding signal all the way to pin 7 of IC2, but not to R20. I then made a solder bridge from IC2 pin 7 to the same end of R20 where C11 connects to. Now I get a signal - but it feels like there's too much gain, it's basically a farty fuzz and the volume pot doesn't make any difference. But at least there's progress.

You may have a Dud Volume Pot?
Here is a Continuity test for all connections to the Volume pot.
Make sure Pin 7 & Pin 6 are not bridged!, no Continuity.


It is more Overdrive into Fuzz with a Clean Amp:

 

[Fama]

You may have a Dud Volume Pot?
Here is a Continuity test for all connections to the Volume pot.
Make sure Pin 7 & Pin 6 are not bridged!, no Continuity.
View attachment 54742

Well, at least that problem was easy to find - pin 7 doesn't connect to anything at all (except that R20 where I made the connection manually). So I connected C11 to IC2 pin 7 too - the connections between C11 and the volume pot and C11 and pin 6 of IC2 were fine. Now it works and sounds as it should - it's pretty dark, I kept the tone control around 80-100% for the whole time I was testing it, but that's close enough for rock'n'roll as they say. Thanks a lot for your help!

Edit: Looking at that video, I'd say the tone works about as it should too.