This circuit was found in an American documentation from the 90's. The transistor is a general purpose one. The circuit oscillates well between 12 and 30 MHz with the indicated components.
The voltage of 13.2 V is closer than what we find in a car battery than 12 V. Thus, a 13.2 V zener...
We found this circuit in a 1998 documentation. It is based entirely on relays that must have...
This effect for guitar was found in an English magazine from 1978. The transistors can be the most...