We found this circuit in the October 1987 Radio Electronics magazine. The triac must be controlled according to the heater. The transformer has a low current, of the order of a few hundred mA.
This circuit generates signals from 0.01 Hz to 10 kHz, but uses unusual components today. The...
This circuit was obtained in a 1973s documentation. The transistors may be BC558 for the PNP and...
This CMOS circuit for LED displays is from a Radio Electronics magazine from February 1989. The...