This circuit uses, as a main component, an LDR (photoresistor). An LDR changes its resistance value depending on the amount of light it received. The more light means less resistance, the less light means more resistance.

The post Dark detector circuit using LDR and relay first appeared on Electronics Area.

The post Dark detector circuit using LDR and relay appeared first on Electronics Area.

This circuit has many applications on places where it is necessary to activate and deactivate (connect and disconnect) an electrical or electronic device.

The post ON-OFF Switch circuit using a 555 timer (PCB) first appeared on Electronics Area.

The post ON-OFF Switch circuit using a 555 timer (PCB) appeared first on Electronics Area.

The LDR varies its value (ohms) depending on the amount of light that illuminates it. The more light less resistance and less light more resistance, A potentiometer is used to control the light level that activate the relay

The post Light Operated Relay Circuit using LDR / Photoresistor first appeared on Electronics Area.

The post Light Operated Relay Circuit using LDR / Photoresistor appeared first on Electronics Area.

This circuit detects if there is a difference of lighting between two LDRs, and sends an audible and visual warning. Circuits that use two LDRs are more reliable than those that use only one.

The post Shadow detector alarm circuit with two LDRs first appeared on Electronics Area.

The post Shadow detector alarm circuit with two LDRs appeared first on Electronics Area.