Found in an American documentation from 1969, this astounding circuitry makes a relay operate on 3 Hz cycles. The relay is of the high voltage type of the time.
This small-range MW transmitter can be used as a wireless microphone. The circuit is from an...
This single-transistor oscillator was found in Radio Electronics magazine from February 1962. The...
This source for common, non-high-power car radios can be used on the bench. It was found in a...