This trigger uses two switching transistors that can still be found with some ease. The circuit is from an old documentation and its purpose is to speed up the switching of logic circuits.
The circuit is from Motorola's Linear Databook from 1990, but the configuration is current because...
In the figure we have the simplest way to implement a power supply for a tunnel diode. The...
This circuit was found in documentation from the 1980s. The circuit can be implemented with other...