This sonic relay or vox was found in a Popular Electronics from the 90's. The power MOSFET can be of any type determining the controlled load.
This circuit is an application for an operational amplifier with field effect transistors from...
With the circuit shown, you can turn the lamp on or off in the living room, without the need to...
This simple circuit aims to visualize the modulation of a signal from a transceiver. Capacitor C1 is from...