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, found in a 90s Popular Electronics, uses a 0 to 1 mA milliammeter, which can be...
This configuration is from a 1966 publication. However, with small changes in component values it can...
I found this circuit in a 1978 publication. The circuit can be assembled with a BD136 transistor to...