This circuit transmits the audio signals from a telephone line to an FM receiver placed nearby. The coil has 4 turns of wire 28 in the form of 1 cm without core. The trimmer is 2-20pF or greater.
Found in a 90s ARRL Handbook, this circuit is intended for the production of signals in the side...
This is the circuit of a hearing aid amplifier manufactured by Sony in the 1960s. The circuit was...
This variable frequency oscillator generates signals that have a recurrence frequency determined by...