Hello folks, back with another headache. Been having issues with a Russian BM build and I can't figure it out, been through the schematic countless times but still banging my head against the wall. Followed the Debugging sticky so here's the lowdown.

No sound coming through.

http://4.bp.blogspot.com/-j0xvHzA3bqE/UR_L2rWBQkI/AAAAAAAAE6M/xAS0_FdiQc0/s1600/EHX+Green+Russian+Big+Muff.png 

Changed the cap on switch from 10nF to 12nF
7.Turn your meter on, set it to the 10V or 20V scale. Remove the battery from the battery clip. Probe the battery terminals with the meter leads before putting it in the clip. What is the out of circuit battery voltage? => 8.8V

Voltage at the circuit board end of the red battery lead = 8.68V
Voltage at the circuit board end of the black battery lead = 0V (is this not connecting ground to ground though?)

Q1-
C - 3.95V
B - 0.63V
E - 0.03V

Q2-
C - 3.88V
B - 0.63V
E - 0.3V

Q3-
C - 8.1V
B - 0.49V
E - 0V

Q4-
C - 3.77V
B - 1.51V
E - 1.01V

Dx-
A - 8.64V
K - 8.46V

D1-
A - 0.39V
K - 0.63V

D2-
A - 0.63V
K - 0.4V

D3-
A - 0.49V
K - 0.27V

D4-
A - 0.27V
K - 0.49v

I was wondering if it would be possible if someone could let me know how to diagnose the issue with this information? I guess it's some kind of math churning involved? I don't like not being able to fix these problems myself, feel you guys are probably sick to the teeth with these posts so any help would be hugely appreciated.

Thanks in advance!

Chris.

Something to do with that 15k resistor on the collector of Q3?

I am no expert but I assume the voltages on Q3 aren't right. Maybe check the components around it. Little mistakes like messing up a 100ohm and 100k resistor that are beside each other happens all the time.

GOT IT
Sorry guys, been a complete numpty and didn't realise I had wired the sustain wires upside down. YAASSS
Had a feeling this was going to be a total nightmare build, but simple fix!

sounds cool...though, it doesn't explain the high Q3C voltage rousejeremy noted...or the reason you were getting no sound. Shouldn't it just have reversed the sustain sweep?

Q3-
C - 8.1V
B - 0.49V
E - 0V