Russian Big Muff modification issue

[scott_v]

So i've sorta heavily modified my newer Russian Big Muff Pi and having some weird issues with the Sustain pot,  where when full counterclockwise it basically silences the unit when the effeect is engaged.  Not sure where to begin on troubleshooting the issue but this is what i've done:

Removed the first pair of diodes, replaced the second pair of diodes with LEDs (which did light up but not any longer...could be part of the problem???) had to replace Q3 because the original was damaged (maybe the issue is here?) 

[bumblebee]

You need a limiting resistor on the sustain pot to stop all the signal passing to ground, 1k will be fine.
There will already be one there unless you have removed it?

[scott_v]

I don't believe there is one there, but i'll check the board again, i have 2 other russian big muffs and neither have a 1k resistor on the sustain pot. so i'm kinda still a newbie on this stuff and not exactly sure what you mean... put the 1k resistor across lug 1 and 2 or 3 and 1.

[bumblebee]

No, No, put the resistor from lug 1 to ground, unless you removed it there will be one already soldered to the PCB. Follow the wire from sustain pot lug 1 to the PCB, it should then go into a resistor which then goes to ground.

[El Heisenberg]

Thr resistor is supposed to be at the "end" of the potentiometer, which is just a variable resistor. When the pot is turned all the way down so that, in this case, the variable resistornis not resisting at all, then the 1k resistor is there to keep all the signal from going to ground. With out it there, all the signal goes to ground.

You could just remover the wire from lug1 and solder the 1k resistor to lug 1 of the sustain pot and connect it to the wire, or just connect it to lug 1 of the volume pot, which goes to ground. These ways you dont have to mess with the board.