This protection circuit was obtained in a 1969 Electronic Design. The SCR can be the current equivalent, depending on the fuse current.
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...