Help! Fuzz Face Ge pnp stopped working

[andrewz]

Hey guys,
a couple of years ago I built a germanium fuzz face pnp from scratch. It worked perfectly until a guitar-playing buddy of mine came over one day and probably plugged in a wrong ac adapter, not knowing anything about the positive ground.. after that, no sound.. Now it's been a while since it died, and I need help getting it back working!

here's a little more info:
the schematic I think I used:
http://www.pisotones.com/FuzzFace/imgs/fuzzface.pdf
and the layout I think i used:
http://img402.imageshack.us/i/fuzzfaceturretlayout.gif/sr=1

My buddy didn't really know which ac adapters he tried plugging in, but the only possible adapters around that fit were a multi-plug 9v or an 18v. He could have plugged in one of these, or both..
Although the FF is pretty simple, this build was admittedly maybe a little over my head - I'm a novice at electronics, and never really understood the positive ground aspect of this pedal.. Plus, I built it several years ago and have forgotten almost everything i even learned about the pedal.. So troubleshooting this on my own isn't really an option, I need some advice!! I would assume that there is something specific that commonly goes out when the wrong polarity/voltage is introduced.. What should I check, and how do I check it? I'd appreciate any ideas on how to check/fix this pedal - it sounded amazing when it was working! Let me know if any more info is needed..Thanks in advance!

[Jhouse]

Could you post some voltages? That would help us out a lot. Use THIS as a guide for telling us the stuff we need to know.

Also, it could just be your electrolytic capacitors. They break if your screw up their polarity.

[petemoore]

  Protection diode not shown.
  This means AC or Reverse Polarity probably got in there.
  Ac adapter can't do DC or reverse DC, so we'll assume Ac got in, worst case, everything polarized fried.
  Or Reverse DC got in...
  The resistors are fine, the RP'd electrolytics should be tossed, the transistors...
  I'd check for DC blocking of in/out caps, remove the electrolytic, power it with correct polarity DC, and check the transistor voltages. If they look ballpark operational, put a new 22uf gain-cap in, connect it to amp.
  Still no go ?
  Could be the transistors got a taste of AC, are no longer.
  The other little caps...if they're actually bipolar/nonpolar [should be] and rated for >the voltages they were exposed to, they should have survived.
  ie that leaves basically resistors, the board and some wires. 
   
 

[Jhouse]

ie that leaves basically resistors, the board and some wires. 

At least that circuit isn't much more than that to begin with anyway.

[andrewz]

Sorry guys, I meant to say dc adapters, not ac.. No ac has been introduced, just wrong polarity and/or 18v..
I'll get voltages of everything tonight. I just figured this "accident" probably happens pretty frequently and might have a standard repair procedure. Oh well.. Thanks again, I'll come back with the voltages.

[petemoore]

  Reverse polarity DC is less destructive than AC..it's probably just the electrolytics for certain.
  The transistors can be measured for goodness [ie fire the circuit up and see how they bias and sound].
  The non-polar components don't care about RPolarity.