Found in a 1960s documentation, this circuit uses a transistor to drive a relay as well as a set of neon lamps with high voltage power supply.
Indicated for activation by microcontrollers, this circuit was found in the Radio Electronics...
We found this circuit in an English publication in 1991. The circuit can be assembled with...
This tuner circuit was found in an old English documentation. The JFET can be any general purpose...