EA Trem issues...

[Shandy]

Hi folks... I searched the forums for some clues, and spent enough time with this pedal to pull out a sufficient amount of hair.  I recently built a Green Ringer and then an OmniDrive with not much trouble, but this EA Tremolo is driving me crazy.

Just the facts, ma'am...

- Schematic: http://www.generalguitargadgets.com/diagrams/eatrem2_sc.gif

- Layout: http://www.generalguitargadgets.com/diagrams/eatrem2_lo.gif

- The unit passes a clean signal when it's bypassed, but no signal at all when I switch it on.

- The only mod or part substitution is I replaced the 3PDT switch with a DPDT, but I'm confident in the wiring, as the same scheme has worked for me on other pedals in the past.

- Battery voltage: 9.04v

- The voltage is getting to the PCB with no loss.

Q1
C: 6.08v
B: 1.38v
E: 0.84v

Q2
C: -0.47v
B: 0v
E: 0v

Q3
C: 4.30v
B: 0.57v
E: 0v

Q4
C: 8.99v
B: 8.27v
E: 8.28v

And here is where my ignorance will really shine: When I do the pokey trick with the audio probe, I get a signal at the PCB input as well as  on the R1 side of C8, but nothing gets through to the other side (R16)... obviously, if the signal can't get through C8, it can't get to the rest of the effect, right?

Thanks in advance...

[Threefish]

the audio probe is the way to go. I can't comment on the voltages, but I think your C8 says it all. At least some signal should get through it. Try replacing it. After that, check the usual transistor orientations, solder connections etc.
A friend of mine built this GGG version, and some problem with it drove him nuts until in exasperation he swapped the two FETs and transistors. Then it started working. 
Don't give up - it's a lovely trem. I built the ROG version using the MOSFET first stage with some mods. My build report : http://www.diystompboxes.com/smfforum/index.php?topic=45546.0

[aron]

Q4
C: 8.99v
B: 8.27v
E: 8.28v

Something seems wrong right here.

R15 and R16 form a voltage divider so the voltage on the base of Q4 should be much less (about half?) of V+

Aron

[Shandy]

HA!  Found a typical rookie short near Q4... thanks for pointing me in the right direction.

I have it working, but the output is pretty low, compared to the bypassed signal.  But I'll take what I can get for now and come back to it later.  Thanks!