Dead Fuzz Face

[Deep Blue]

Ok, so I built a fuzz face and it sounded and worked great for a few days.

I boxed it up and used it for night, and when I tried it the next day, it wasn't working.  It was transported between houses once or twice, so it may have been banged around a bit, but not enough to do serious damage, I don't think.

I can play on bypass mode, and the LED works, but when I turn the pedal on, I get nothing.

The pots give me a reading with my meter, and there is no visible damage to anything.  All the solder joints are fine, and everything on the PCB is in order.  I had a strip of thick foam padding between the PCB and box, so I can't imagine anything happened there.

What could it be?  Could it be the germanium transistors?

I built JD Sleep's PNP transistor negative-ground version.  The two-knobed one.

[Craig V]

It's probably not the transistors.  I'd bet it's just a loose connection somewhere - maybe a wire somewhere or one of the traces on the PCB.  

A really useful tool for figuring this out would be to make the audio probe suggested by Aron on his debugging page.

Or I personally just use an old guitar cord, and one of the ends is cut off - just connect the ground to the ground of the good cable coming from the guitar, and use the hot lead to trace where the signal looses power.  Oh yeah, you have to plug the probe into an amp.  

Did you check to make sure the transistors are recieving power?  The collector of Q2 should recieve about 4.5 to 6 volts.

[petemoore]

Often times when I'm 'boxxin a ckt something gets to touching where it souldn't.
 Funny Jax or switch probs too.
 I've been known to just pull the ckt out from the bypass, switch JAxx,  and box, figure out whats going on, stick something else in there [I'm not fond of Boxxing Vs ckts]
 As much as I hate it, I have to debug ckts and find cold solder [just did that on the BlackFire today] yupp I've been lucky tohave these problems mostly not at gigs...had to eliminate pedals a couple times at gigs.
 I've gotten pretty quick results before with just the DMM checking ALL connections for continuity ... clamp - to ground and check all grounds/and positives connections likewise from the top rail from under the board to the tranny's socket lugs...the one thing I can't check this way is caps [never had a bad one yet, never heard of one though I'm sure it's happened] resistors are notoriously dependable [long as they're 'rated for Voltage]
 ""sometimes" R value can be found on resistors in ckt but off values should be ignored
 When they mess up I resolve it oculd be anything, though I always start with the easy / obvious pin V's and such...
 I just get a Buzz sound going [live amp input/cable/thumb on sleeve&tip] connect the amp to the output start at that juncture with the metal poker [screwdriver] and adjust the volume so I can hear Buzz when on the ckt side of that, then the 'inside of the ouput cap' following deeper and deeper into the center of the ckt from the output  to see where I lose the buzz. Where a transistor is amplifying [like both in a FF] the buzz should usually be louder at the base than the collector, emitters
I skip.  get it going and the source [thumbtip audio probes fine for me with low voltage ckts] should sound the most amplified at the input