This old circuit from a documentation from the 70s disconnects a TV from a signal obtained on the TV itself, detecting when the tuned channel goes out of the air.
Although MOSFETs of the type indicated are not very easy to obtain, one can have the circuit as a...
This power source takes advantage of an old valve transformer that is no longer used and can...
Found in 90s Popular Electronics, this circuit fires a load through a MOSFET from an audio signal...