This is the circuit of a power supply supplied in a kit at the time. The circuit is in the September 1974 Radio Electronics magazine.
This circuit is from 1968 documentation. We can assemble it with more modern components such as a...
Found in a 90s Silicon Chip documentation this circuit is intended to protect a speaker system in...
The UVTRON tube is an ultraviolet radiation sensor. In this circuit from Radio Electronics from...