Found in an Electronic Design from the 90's, this circuit uses an SCR according to the controlled power. The circuit is for 12V heating elements.
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...