Photo Cell CdS Photoresistor 10pcs - LDR Pack starter kit v3 or playback projects

or playback projects

and periodic checking if you want stable readings

A 2G Mini SIM card is required to do anything on the cellular network

4GHz spectrum wireless protocol

Compact size: 46 × 34 mm

Photo Cell CdS Photoresistor 10pcs - LDR Pack starter kit v3 or playback projectsCdS cells are little light sensors. As the squiggly face is exposed to more light, the resistance goes down. When its light, the resistance is about 5 10K, when dark it goes up to 200K. To use, connect one side of the photo cell (either one, its symmetric) to power (for example 5V) and the other side to your microcontroller's analog input pin. Then connect a 10K pull down resistor from that analog pin to ground. The voltage on the pin will be 2. 5V or