How to Set Bias on Dunlop JDF2 Germanium Fuzz Face

Just a quick display of my method of biasing the germanium transistors in the Jim Dunlop JDF2 Fuzz Face. It’s an easy process made harder but the fact that this version of the Fuzz Face has a different arrangement of trim pots than what is standard today.
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[@poynt99]

You may have the transistors and associated pots mixed up: TP1 is for Q1, and TP2 is for Q2. Q1/TP1 are in the middle of the pcb, and Q2/TP2 are at the outside edge of the pcb by the two big 330uF caps. TP changes will affect the other Q's bias, which is perhaps what you are seeing. Slight correction: TP2 is actually the 100k feedback pot (which seems to be set to 0R in many cases) in series with the 56k feedback resistor. Interestingly, there is no collector bias pot for Q2.

[@blashuvec]

Will this work if the fuzz face had a 9v adaptor installed? It's still a JDF2 just w/o using a battery.

[@pfg_pedals]

Yes the bias process will be the same provided it was installed properly.

[@poynt99]

Just be careful and aware that this is a PNP-based fuzz, therefore you should only use a 9V supply that is isolated from your other 9V supplies.