This circuit is from a 1969 EEE magazine. The transistors are from that time, but the circuit can be implemented with modern equivalents, such as 2N2646 for Q3.
In the figure below we have the typical circuit of an automotive star alternator with the...
This simple pass-through circuit was obtained in an old documentation, but it is still up to date...
This circuit was obtained in a 1974 National Semiconductor components and circuits manual. The...