This circuit that appears in several versions in this section and on this website was found in documentation from the 1980s. The transistors can be of any general purpose NPN type like the BC548.
We found this circuit in the March 1992 issue of Radio Electronics magazine. The circuit has a...
The circuit presented may use any general purpose transistor. The indicator is an LED and...
This unusual audio amplifier configuration was obtained in a 1974 documentation. The PNP...