This simple radio was found in a Popular Electronics from the 90s. L1 and L2 have 100 turns on a toroidal core and L1 have a socket on the thirtieth turn.
This circuit separates the bass from the treble in an audio signal. The circuit is from a Hands On...
This circuit was obtained in a 1986 documentation consisting of an active frequency divider for...
We found this circuit in a Popular Electronics from 1992. It consists of a voice scrambler used in...