Process timer (CB21865E)

We found this timer for times of a few minutes in a 1974 Ferranti transistor manual. The relay is 37 mA sensitive type.

Remote control for antenna (CB25104E)
This is perhaps the first PIC project to appear in a publication. The article is from Radio...
Acoustic transmitter (CB8230E)
From a 90s Popular Electronics, this circuit emits pulsating signals for different types of...
CEM3330 Effects Circuit (CB24745E)
This circuit for effects on music synthesizers was found in the May 1983 issue of Radio...