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 was found in a 90s EDN. It activates a protection relay in case of reversing the...
With the presented circuit it is possible to detect signals from transmitters in a frequency range...
This circuit was found in an old documentation for radio amateurs, being indicated for...