This circuit is from Dutch documentation from 1967. The circuit works with a component of the time, the BRY39, which is uncommon today.
This circuit can be used with common drills connected to the 110 V network. With change of R1 and...
When the temperature rises above the value adjusted by P1 the relay triggers on. The rated voltage for the...
The basis of this circuit is the 723, an old integrated circuit not easier to find these days. The...