Unijunction SCR Trigger (CB21469E)

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

Passive Tone Control (CB19183E)
This circuit appears in several versions on this site. It is designed to be used between the...
Ultrasonic Scarecrow (CB12342E)
This circuit uses a piezoelectric tweeter to emit a powerful continuous sound above the audible...
Touch Lamp Control (CB26132E)
This circuit is based on a Siemens S566B integrated circuit. The circuit is from a Radio...