This configuration is from the 70s, having been found in an American documentation. The transistors can be BC549 for Q1 and BC548 for Q2.
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...