We found this multiple thermostat circuit in July 1980 Radio Electronics magazine. It uses opto-triacs for power control and operates on a 117 VAC mains.
This circuit in a receiver that allows the capture of distant stations with short waves. The...
This experimental receiver was found in an English publication in 1979. It can receive medium-wave...
This circuit was found in an Italian publication in 1975. The transistor must have a heat...