This transistor curve tracer was described in a December 1969 Radio Electronics article. It consists of a ladder-type signal generator that applies stepped voltages to the transistor under test.
This circuit is from 1989 documentation. It uses the TDA2002 as a modulator and the unusual power...
This configuration is suggested by Mullard (Philips) in an old manual of 555 integrated circuits....
The figure shows how to use a CMOS amplifier as a crystal-controlled oscillator. The circuit is...