This circuit was found in the January 1996 issue of Electronics Now magazine. The circuit is powered by voltages from 10 to 24 V and has a control for the intensity of the output signal.
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...