This circuit was found in a Popular Electronics from the 90s. It is based on components still common today and an optical coupler for the triac. The sensor is a thermistor.
This circuit uses an LM339 and was found in the July 1995 Electronics Now magazine. The LED lights...
We found this circuit in an old Mullard (Philips) documentation on the 555 and 556 integrated circuit...
This circuit was obtained from an 80's documentation from General Electric. The circuit uses an...