To close out EarthQuaker week, here's the Dirt Transmitter. I traced this one myself and below is a video showing the process. It's similar to a Fuzz Face, but a little different. I found this description from (I'm assuming) Jamie over on TGP:
I guess it's kinda like a fuzz face but it started as two gain stages running into each other with an input gain control and a sag on the second stage (bias). Voltage feedback was added and it became similar to a fuzz face in topology but it sounds nothing like one IMO. In this case the sound is totally dependent on the transistors, replace them and it's a whole different beast.
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I guess it's kinda like a fuzz face but it started as two gain stages running into each other with an input gain control and a sag on the second stage (bias). Voltage feedback was added and it became similar to a fuzz face in topology but it sounds nothing like one IMO. In this case the sound is totally dependent on the transistors, replace them and it's a whole different beast.
Here's my video on tracing the circuit as well as a demo:
Here's the schematic:
And the layout:
You can also order a few boards from OshPark here.