This one was quite tricky to trace. Got the topology figured out quite quickly but but identifying some of the capacitor values was quite difficult with these Greenies with faded markings. Had to look at several units, all had some minor variations but I think the layout below is pretty much spot on.
It is a heavy fuzzy overdrive with the gain control rolled back, maxed out it is a high gain fuzz. Most units had a 100k gain control with quite a limited range. It was later reworked for V4, using a 500kC potentiometer which gives a much more useful range.
It can be quite noisy with the gain maxed out (probably bcause of the layout itself, not the circuit design...) but short wires and shielded by an enclosure helps.
