This circuit was obtained in a 1999 English magazine. We can easily assemble it with a BD136 or even TIP32 transistor and its supply can be made with voltages from 9 to 12 V.
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...