We found this circuit in the July 1994 Radio Electronics magazine. The circuit uses a general-purpose transistor, and the power supply can be up to 12 V depending on the relay.
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...