When the environment becomes dark, the resistance of the LDR increases. An increase in resistance causes the voltage to rise on this element. The increase of the voltage in the LDR transmits the transistors T1 and T2.
Transistors that are transmitting operate the relay. When the environment illuminates, the resistance of the LDR decreases. The resulting voltage decreases. Transistors go to slaughter. The degree of sensitivity of the circuit to the light can be changed by the pot.
CIRCUIT DIAGRAM WORKING IN THE DARK
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