Laser Alarm System




Don't have any of those luxurious security systems? Lack of budget? You can have your own now without spending too much!

Step 1: Materials Needed

For the battery, we used battery out of coins and foil (the one I posted a while ago).

Step 2: Schematic Diagram

Step 3: Connect the Parts.

Solder the parts according to the schematic diagram. Then put in a place where in it is hidden. In our  case, we put it in a flower designed pen. I wrapped some parts of it with a electrical tape to secure them properly.

Step 4: Test It.

As you turned on the switch, the buzzer rings continuously but when you point a laser on it the ringing sound will stop.  Multiple reflections can be created by using mirrors to make it more complicated just like in the movies. :)



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    5 years ago on Introduction

    I would like to make one if I knew more about electric wiring. I have no idea what that is on the left in your schematic. Could you explain more. I wired my shop with 2 sirens, 6 zones, 3 PIRs, 8 magnet door switches, 3 windows w/foil tape, smoke detector, and EOLRs on all, but I am too dumb to understand your drawing.

    What happens if someone breaks the laser beam momentarily? Does the buzzer keep buzzing or turn back off?

    That photo of "Photocell" in step #1....can that carry 100 Watts at 120 Volts?

    Interesting, thanks for posting.