In this 1990s circuit, found in a National Semiconductor manual, the output voltage is the square of the input voltage. The components are from the period.
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...