Automatic light control lighting circuit 2

(2) The second circuit of the automatic light-controlled lighting circuit is shown in Figure 2-87. It uses unidirectional thyristors. Capacitor C also plays the role of anti-light interference, and resistor R2 plays the role of current limiting . Adjust the potentiometer RP so that the light EL goes out when the photoresistor RG is exposed to light. If automatic control is not required and the lighting lamp needs to be lit at any time, switch SA can be used to control it.