The Zonk Machine was one of the many British fuzz boxes that came out in the mid-60s. Like the Tone Bender Mk II it was designed to compete with, it also was featured 3 germanium transistors but offered more of a boost and slight oscillation (in a good way). This is a positive ground effect so unless you use a charge pump or can make it work with NPN germanium transistors you can’t daisy chain it with other negative ground pedals. If you are going the NPN route, be sure to rotate the polarized caps an the diode 180º. Here’s the schematic for reference.
