This circuit for incandescent lamps was found in a 70s documentation. The circuit uses an SCR according to the power of the controlled lamps. The delay is a few seconds, given by capacitor C1.
This is the simulation of a Ultrasound Receiver using the 741 IC, an operational amplifier....
The resonant circuit depends on the crystal frequency that can go up to a few megahertz. The...
With this circuit it is possible to select the upper or lower side band on an SSB transmission by...