We found this circuit in a 1980s documentation. Equivalent components can be used. The circuit senses temperatures in the range of 0 to 50º C and uses a transistor as sensor.
We found this circuit in the 1982 Selezione Radio magazine in Italy. The circuit uses an...
This circuit was obtained from Dutch documentation from 1967. It uses transistors of the time...
This circuit was found in a 1966 General Electric book. The triac and the day are from that time...