desk lamp remote control circuit

The 220V AC voltage is stepped down by the capacitor C], the rectifier bridge stack UR performs barrier wave rectification,
the capacitor Cz filters, and the voltage is stabilized by the Zener diode and becomes a DC voltage. '
    The resistance of the photoresistor RG is very small during the day, and the pulse signal charging the capacitor C3 is very small, which cannot trigger the thyristor to conduct, the EL circuit of the bulb
is blocked, and the bulb F:I_ does not light up; when night falls, the dark resistance of the photoresistor is very large, The charging pulse signal to capacitor
C3 is very large, which can trigger the gate of the thyristor, causing the thyristor to conduct. At this time, the relay coil is energized, and the normally open contact of the relay in the EL circuit of the light bulb is connected, and the light bulb EI
lights up . .
    Adjusting the potentiometer RP can adjust the size of the trigger signal to the gate, thereby adjusting the conduction angle of the thyristor, thereby controlling the brightness of the bulb
.