Found in an Electronics World of 1968 this circuit can use current SCRs and the diodes are according to the lamp. The Circuit only works with incandescent lamps.
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...