This sensitive circuit for triggering relays was found in an old English publication. It works with alternating signals applied to its input. Transistors are general purpose types.
This circuit with 117 V output was found in a 1969 Electronic Design. Drive transistors admit...
This project came out in an article of mine (Newton C. Braga) in the Popular Electronics magazine of...
Found in an Electronic Design from the 80s, this single cell charger uses an integrated circuit...