This circuit is part of an integrated circuit tester published in an article in Radio Electronics magazine in September 1985. The circuit is powered by a 9 to 12 V source.
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...