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.
The transistor may be the BC548 in this circuit for low frequency signals. We found it in an old...
Found in a 1980s American documentation, this circuit is intended for amplifying 10.7 MHz video...
This circuit can be used with older tape player systems to recover media converting for digital...