Constant current source (CB20484E)

This circuit uses a current regulator from the 90's. This component is uncommon nowadays. The transistor admits equivalent.

Signal Injector and Follower (CB18811E)
This ultra-simple test circuit is of great use in any electronics bench. The power is supplied by a...
12-Bit A-D Converter (CB5025E)
This circuit was found in an Electronics World magazine from 1990. The circuit can be mounted...
100 MHz harmonic oscillator (CB9659E)
This Pierce oscillator was found in American documentation from the 1980s. Transistors support modern...