This simple receiver of two transistors for the 80-meter range was found in an American documentation from the 1980s. The transistors admit equivalents and the antenna must be long.
This circuit was found in the March 1979 issue of Radio Electronics magazine. Integrated circuits must...
This is the transmitter for a remote-control system published in the August 1986 issue of Radio...
The current drained by this circuit, from a 1976 documentation, is 3 mA and the cut-off frequency is...