In fact, it is a night light system that automatically turns on the outside lights when it gets dark and turns them off at dawn. The circuit only applies to incandescent lamps.
This circuit was obtained from an American 80's documentation. The balanced mixer can be shown in...
This circuit produces a square wave signal with the frequency determinated by R1 and C1. The upper limit...
In the figure we have the circuit of an amplifier for alternating signals with 10 times gain,...