Here are some DIY LDR switch circuits available on our website and the web. LDR switches are used to switch a relay or other device when light are present or absent. LDRs or Light Dependent Resistors ...

This article explains an upgraded smart solid-state AC switch system that uses microwave Doppler radar instead of traditional ...

This home smoke detector circuit warns the user against fire accidents. It relies on the smoke that is produced in the event of a fire and passes between a bulb and an LDR, the amount of light falling ...