I have a 2 knob MJM Brit Bender that I've used for about 5 years that has recently developed a large amount of hiss. So much that it is unusable. The transistors are unmarked PNP germanium. I've ruled out any problem with the rest of my rig.
I tried swapping the transistors with some known good ones from another TB clone I have but the hiss was still there. Any ideas what else in this circuit could cause it to start hissing?
Measurements:
Power supply voltage: 9.27v
Q1: C= -9.27v B= -0.01V E= 0
Q2: C= -0.31V B= -0.11V E= 0
Q3: C= -5.18V B= -0.31V E= -0.21V
The layout is similar to a Marshall Supra Fuzz. Here is an edited schematic with the differences in RED:
https://ibb.co/wpMMXYS
