SOLVED Intermittent (Intelligent) Bypass Board, a finger touch turns it on, I need ideas

[xefned]

I cannot locate the short on this bypass board.

I've reflowed all the wires and both sockets (IC and relay.) Resoldered the 2n3904 switch transistor, etc. Is there some edge case where the transistor won't switch?

The reason I ask is because I'm using Intelligent Relay Bypass on everything now.
After 5 successful bypass boards—my last 3 did not work. <-- I attributed that to bum ebay relays. I tested this one before I installed it (with a relay from Robert) so I thought I'd be good.

Any unusual ideas?

 

[benny_profane]

Did you solve this? The transistor is just for the LED.

 

[xefned]

The problem was NOT the bypass board.

None of you will be surprised to hear: the circuit works fine now. And I don't exactly know why.

The official prognosis is: circuit freakout.

1. Touching another electrolytic on the main board also made the sound cut out.
2. Gripping the enclosure by both sides also caused the sound to cut out.
3. This is a Velvet Fuzz, and the problem only happened in tight mode.

I trained all the JFET drains to 4.5v and now it's almost impossible to replicate.
Working fine now:



Now the only thing that makes it cut out is to
• put it in tight mode and touch the LM386 •



Maybe just a fluke, but it would be interesting if anyone else had that same issue.
It's a non-issue since it's impossible to touch the LM386 with the lid on.
i.e. perfectly functioning Corduroy fuzz.

 

[xefned]

Did you solve this? The transistor is just for the LED.

Oh, good to know. Thanks. I never really analyzed the Bypass board.

It's the best thing to happen to DIY pedals ever. I wanna use it on everything I build now.