This circuit for the power grid was found in the June 1969 Radio Electronics magazine. The SCR and diodes are rated according to the power of the controlled load.
This circuit was obtained from an American 1980s documentation. The frequency depends on the...
This traditional metronome circuit is powered by voltages from 9 to 12 V and output drives a...
Found in a 1966 documentation, this “coin finder” uses components from the era operating at 2.1...