This circuit is from Mullard 1969 documentation. The circuit operates at a relatively high supply voltage and has a 10 Vpp output. The transistors are of the time, but admit equivalents.
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...