Infrared Alarm

Posted on Aug 25, 2012

This circuits consist of two parts, the first part will transmit a signal, and the second part will detect that signal and trigger a relay.To adjust the circuit, hold down S1 while pointing LED1 at the receiver. Adjust R6 until you hear the relay click. You can increase range by using a high output LED for LED1. Bright light will stop the receiver from responding to the transmitter.

Infrared Alarm
Click here to download the full size of the above Circuit.

You can use the designed PCBs to build the circuit simply:

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