Parentheses Fuzz with Intelligent Relay Bypass

[ozdixon]

Hey everyone, I am having some issues with the Intelligent Relay Bypass on the Octave switch for Parentheses Fuzz. I am getting no octave effect, both boost and fuzz work. There is an insanely high noise even with gain turned down. When fully Turing octave pot the there is no sound, other wise it has no effect. The momentary switch doesn't have any effect. When I turn it on the octave led blinks and either stays on or give a click and turns off. It seems to alternate randomly.

 

[Diynot]

As per our last conversation, did you visual inspect the board for shorts/cold joints and verify components? Also, if you look at the second wiring diagram in the build doc, it shows you how to wire the board with no footswitch for the octave/octave always on. Try removing the relay board altogether and jumping these 2 spots to verify whether the octave section is working or not. If it’s working that way then we know it’s the relay wiring that is wrong

 

[ozdixon]

I did look over things and cleaned the board a few times. I agree I'll remove the whole bypass and see what happens.

 

[ozdixon]

As per our last conversation, did you visual inspect the board for shorts/cold joints and verify components? Also, if you look at the second wiring diagram in the build doc, it shows you how to wire the board with no footswitch for the octave/octave always on. Try removing the relay board altogether and jumping these 2 spots to verify whether the octave section is working or not. If it’s working that way then we know it’s the relay wiring that is wrong

Hey so I removed the bypass and the problem persists. When I turn the octave pot down it cuts the effect, when I turn it up I get that loud background noise and this sort of squeal, it hard to describe, I almost didn't notice it at first.

 

[Diynot]

Kind of guessing here, but can you try flipping the diodes in the octave section so the bands face the opposite direction. Keep the 2nd and 3rd pad of the octave switch connected

 

[ozdixon]

Kind of guessing here, but can you try flipping the diodes in the octave section so the bands face the opposite direction. Keep the 2nd and 3rd pad of the octave switch connected

So, I flipped those diodes and swapped them out for another type, and the effect is the same. So the issue must but the chain I am assuming. I think its time top bust out the multimeter.

 

[Diynot]

Do you have an audio probe?

 

[ozdixon]

Do you have an audio probe?

I do.

 

[Diynot]

Try probing through the octave section of the schematic to see where you are losing the signal. You should start at C3 and check the signal at the base of Q2-4 and then C7

 

[ozdixon]

Try probing through the octave section of the schematic to see where you are losing the signal. You should start at C3 and check the signal at the base of Q2-4 and then C7

Let led me right to my issue. Every single 47R and 47K I mixed up.

I am going to redo these and then try the bypass again.

I was building another one for a friend and I managed to do those resistors correct.

 

[ozdixon]

Try probing through the octave section of the schematic to see where you are losing the signal. You should start at C3 and check the signal at the base of Q2-4 and then C7

Ok now I am confused, I replaced those resistors but still get no sound after C3.

 

[Diynot]

Good catch on the resistors. Visual inspection can usually solve 90% of issues. Are you getting sound from one side of C3 and not the other (the PF5102 vs the 2n5089 side)? My next step would be to reflow the solder joints through the octave section. Just don’t heat the transistors too much.

 

[ozdixon]

So, I turned up the gain on my probe and was able to hear sound coming out of Q4 and Q3. So I plugged it in regular and a weird thing happened. When I turn off the boost side I got this like old internet connection type sound. I am going to keep checking all my components.

I am using the OP07.

 

[Diynot]

That could just be the circuit picking up RF noise from your phone or other computer hardware nearby. Do you have octave coming off of the octave pot?

 

[ozdixon]

No, nothing out of the octave pot. I keep coming back to Q2 as that has absolutely no sound coming out of it at all. I might pull it and socket it.

Somewhere between C3 and Q2 I am losing the sound. maybe having the wrong resistors busted it or something.

 

[ozdixon]

ok I do have dry guitar coming out of octave pot leg 1 & 2 after socketing Q2. Usually I don't have this hard of a time lol.

 

[Diynot]

All good happens to the best of us. If you turn the octave pot up, do you start to get octave at pin 2?

 

[ozdixon]

No it just acts like a volume control.

 

[Diynot]

Ok rereading those last couple of posts, I would expect clean signal out of pins 1&2 of the octave pot with or without the transistor switch because the pot is a basic passive mixer and that is why it is acting like a volume pot since you are mixing out the clean and since you have no octave to mix back in……. Let’s go back to the statement that you do have signal at Q3 and Q4, that means you do have signal through C3 and Q2. Did you verify that the correct transistors are installed in the correct spot in the correct orientation (by that I mean do you have a way to verify the pinouts of the transistors you have in stock)? Can you take some voltage readings on those transistors? And I can’t stress enough the benefit of reflowing the joints if you haven’t already.

 

[steviejr92]

When I turn the octave pot down it cuts the effect, when I turn it up I get that loud background noise and this sort of squeal, it hard to describe, I almost didn't notice it at first.

Ok this sounds like its oscillating. Now as you have it does it still squeal? Just getting in on this and need a little help understanding whats actually going on here. Please be patient with me just trying to catch up lol