This thermal control circuit appeared in Radio Electronics magazine in October 1958. The circuit is powered by the power grid and has two sensors that operate in a differential mode.
The circuit shown is from an old European publication. In it we have the way to activate a relay...
We found this circuit in a European publication from the 1990s. Transistors are still common types...
This circuit was found in an American documentation and can be added to common amplifiers of any...