Hi everybody, after only reading here for a while and completing my first FFs (thanks for the great advice in this forum!), here is my first post:
I am stuck. I am building the Jack Orman PNP fuzz face with negative ground. Kicked the fuzz pot, kicked the volume pot, and put a 10k resistor on the output in there for now. I want to have a one knob fuzz.
Instead of the R8.2k bias resistor I put a 10k lin pot in there. The transistors are matched MP40A, hfe around 33. Itworks, and sounds great. Guitar volume does its thing, it goes from just a little boost to a nice low gain fuzz.
Problem is: when turning the bias pot, collector voltage on Q2 only changes from 9.1V to 8.94V. That should be more. I tried putting different resistors in series with the pot, nothing changed.
I checked the wiring, but I can’t find the problem. Anybody have any suggestions?
Thanks!
Jörg
I am stuck. I am building the Jack Orman PNP fuzz face with negative ground. Kicked the fuzz pot, kicked the volume pot, and put a 10k resistor on the output in there for now. I want to have a one knob fuzz.
Instead of the R8.2k bias resistor I put a 10k lin pot in there. The transistors are matched MP40A, hfe around 33. Itworks, and sounds great. Guitar volume does its thing, it goes from just a little boost to a nice low gain fuzz.
Problem is: when turning the bias pot, collector voltage on Q2 only changes from 9.1V to 8.94V. That should be more. I tried putting different resistors in series with the pot, nothing changed.
I checked the wiring, but I can’t find the problem. Anybody have any suggestions?
Thanks!
Jörg
