Strange pedal problem...please help.

[blues_mang]

Ok, I've built over a dozen pedals and have never had this happen and I can't for the life of me figure this out. I just finished building an ultra simple boost circuit, and it's not working... not getting any audio. So, I first checked continuity and everything checks out. Now for the weird part. I took my audio probe and started at the input jack. When the pedal is in bypass, I touch the probe to the tip solder lug and I get audio. I press the 3PDT and touch the probe to the same lug and now there should be still be audio at the input jack because the signal input doesn't change. The input is always coming in through the input jack. Well, no audio. I don't understand it. I use the same true bypass wiring on the 15+ pedals I've built and have never come across this. The bypass should have nothing to do with the input, so why is this happening? I even checked continuity between the input cable tip and the input jack solder lug and I get continuity regardless of the bypass switch position. Can anyone sort this out? I've been scratching my head for hours.

[R.G.]

When the pedal is in bypass, I touch the probe to the tip solder lug and I get audio. I press the 3PDT and touch the probe to the same lug and now there should be still be audio at the input jack because the signal input doesn't change. The input is always coming in through the input jack. Well, no audio. I don't understand it. I use the same true bypass wiring on the 15+ pedals I've built and have never come across this. The bypass should have nothing to do with the input, so why is this happening?

There's no audio because something in your wiring is shorting the input jack lug to ground when you go to non-bypassed.

Check it with your ohmmeter, power off, no signal. Read ohms to ground  with cord plugged in and effect in bypass. Then press the switch. You should see the ohmmeter fall to 0 ohms or nearly.

Just a guess.

[blues_mang]

R.G., thanks for the quick reply. You're right. Something is shorting the input jack lug to ground. The ohms at bypass are at 68K and drop to 0 when in non-bypass. I just can't figure out what would be causing it because I always wire my jacks and switches the same way.

[blues_mang]

Ok, I found the ground that was shorting the input. It was the ground that I had going from the input jack ground to the circuit. So now it works with no grounds to the circuit board, but of course, the circuit doesn't seem like it's working right. Wouldn't it not work without having some kind of ground to the board?

[petemoore]

the circuit doesn't seem like it's working right. Wouldn't it not work without having some kind of ground to the board?
  Yes.

[blues_mang]

Wow, it's always the simplest circuits that seem to bite ya. I figured out the problem. I had my input on the PCB going to wrong strip on the strip board. Instead of going to the the input cap, I had it on the strip for ground. Everything was shifted down one strip. That's why it was sending my input to ground. Boy, I learned more on this little circuit that I have on many of the complicated ones that worked right the first time. If anything, it forced me to do something I've been meaning to do, and that was to finally make an audio probe. Works great. Thanks all.

-BB