The purpose of this circuit is to improve a trigger circuit using a zener diode. The circuit was found in an American documentation from 1964. It can be improved using equivalent modern components.
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...