I can’t exactly remember how i ran into this schematic. It is pretty old design and once again i’m having trouble finding more information about it. Anyway. I drew it up and built it. Made some slight changes to the original, such as adding the gain knob and one more 1n cap to tame its squeeling down a bit and changing input cap value to let more of the signal in. This is something that i personally enjoyed a lot. Flick of the switch turns it from warm, not completely unlike lightly overdriven Fender amp, smooth OD to high gain monster distortion. I used russian MP25B transistor that i grabbed from measured bag that has 41-50 hFE written on it. I do believe it would work just fine with any PNP transistor in there, but as the design goes, i’d still recommend relatively low gain germanium to be used. I tried different values for the taming the feedback loop, but 1n just felt like the right value. You could (and should) use what you like. I think i need to play around more with this schematic…
Little clip from my circuit. First up, the normal gain and then high. Recorded with single coils:
