We found this circuit in a 1966 US documentation. It simulates a variable capacitor that can vary capacitance from 1,000 to 1. Transistors are general purpose types.
This mechanical reverberator circuit for guitar was found in the February 1970 issue of Radio...
Found in an old English publication this circuit uses a dual gate MOSFET. Coils not specified....
This is the receiver for the previous circuit transmitter. Similarly, no information about the...