This circuit, obtained from a 1965 magazine, can still be assembled using some modern equivalent components. The transistors may be BC558 and the transformer is obtained from a disused transistor radio.
We found this circuit in a Radio Electronics from February 1970. The frequency of 1,400 kHz in the...
This different power control circuit with SCR was obtained from a 1967 magazine. The SCR can be...
We found this circuit in a 70s Electronic Design documentation. The circuit uses general-purpose...