This fuzz effect for guitars was found in an American 1980s documentation. The transistors may be the BC549 and should be battery powered for noise sensitivity. Diodes are commonly used.
This circuit is from a documentation from the 70s. The transistors are types of germanium of the...
Other operational amplifiers in the series, such as the MC34072, MC34074, MC35071, MC35072,...
This circuit is from an American documentation from 1976. The FET can be the BF245 or MPF102 and...