This 600-ohm output impedance circuit was found in a Radio Electronics from October 1963. The circuit uses PNP transistors of the time and is powered with a voltage of 12 V.
The transformer for this project found in a 1986 documentation is an output type, found on old...
This circuit was found in a Popular Electronics from the 90's. It can be implemented with...
This basic configuration can be found in a lot of articles on this site. In this case, the relay...