Unijunction SCR Trigger (CB21469E)

This unusual unijunction transistor SCR firing circuit was found in a General Electric documentation from the 1960s.

Two Transistor Super heterodyne (CB20574E)
This circuit was found in an English publication from 1967. The circuit is for listening on a...
Digital Multimeter Thermometer (CB17031E)
This circuit allows you to use a digital multimeter as a thermometer. The sensor is mounted in a...
Capacitance meter 555 (CB18927E)
This configuration, which appears in other articles on this website, was found in a European...