Although it uses a dual-channel FET, which is hard to find today, this circuit was released in a Radio Electronics issue in April 1986. It serves as a signal booster for a wide range of frequencies.
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...