DIY Kit Photosensitive Sound and Light Alarm Suite Electronic Production Kit for Detect Ambient Light
This circuit Board is used to detect ambient light, the sound and light alarm when the light is bright Supply voltage: DC 3V to 5V Principle Description: W1 is adjustable resistance to adjust the sensitivity of the sensor, GMDZ for the photosensitive resistor, when the light is bright when the photosensitive resistance decreases,
The base current flowing into Q1 is larger, the voltage drop of the transistor collector D1 is lit and R2 is the current limiting resistor. While passing through the R1 stream
The base current of Q2 is also larger. Q2 enters saturation state. SP1 is the buzzer after she got the power also began to sound the alarm.