This circuit is from old American documentation, using a regulator integrated circuit that is uncommon today. The diodes can be 1N4002 and the transformer has a 500mA secondary.
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...