How To Build a Laser Security System

Handle any emergency with Howcast's First Aid app - http://howc.st/jkDRTe

Expand the description and view the text of the steps for this how-to video.

Check out Howcast for other do-it-yourself videos from cognitivefilms and more videos in the Science & Technology Projects category.

You can contribute too! Create your own DIY guide at http://www.howcast.com/videos/new or produce your own Howcast spots with the Howcast Filmmakers Program at http://www.howcast.com/filmmakers/apply.

Got a mystery to solve? Somebody's been making off with your stuff, and you don't have a clue who it is, do you? Here's your chance to catch them in the act.

To complete this How-To you will need:

A laser pointer
Some Duct tape
A few small mirrors
An L.M.741 microchip
A 220-ohm resistor
A photocell
An inexpensive digital camera
An extra small screwdriver
A wire coat hanger
Some thin, insulated wire
A printed circuit board
A 9 volt battery
A 9 volt battery clip
Soldering equipment
A pair of wire cutters
A soap caddy with drainage holes
A voltage relay

Step 1: Build the circuit

Build the circuit. Center the microchip on the circuit board. Pop in the voltage regulator. Connect the battery clip leads to the regulator. Run 2 more leads out from the regulator. Pop in the resistor and the photo cell. Link the chip to the photo cell. Pop in the relay. Link the chip to it as well. Link the other side of the relay to "power."

Step 2: Disassemble camera

Disassemble the digital camera so you can access the board connected to the camera's trigger button.

Tip: You may have to remove the camera's board to get a good solder point on the terminal.

Step 3: Solder wires to terminals

Look for the two tiny terminals that lead to the trigger button. Solder wires to each of these terminals and feed them through the trigger button hole.

Step 4: Reassemble the camera

Reassemble the camera. If you can't get it back together easily, use duct tape to keep it closed. Just don't tape over the lens.

Step 5: Position circuit inside soap caddy

Position the circuit inside the soap caddy so the photocell is exposed behind one of the holes.

Step 6: Connect battery to circuit

Connect the battery to the circuit, and use tape to secure the whole assemblage inside the box.

Step 7: Attach wires to voltage relay

Slip the two wires coming from the camera through another hole, and attach them to either side of the voltage relay.

Step 8: Cut & tape coat hangers

Cut the coat hanger into several pieces. Tape one piece to the laser pointer and the others to the back of the mirrors.

Step 9: Place camera

Place the camera in an inconspicuous location with the lens pointing at the object you want to protect and secure it in place.

Step 10: Position laser pointer

Position the laser pointer in another inconspicuous place and secure it too.

Step 11: Place mirrors

Place the mirrors to create a perimeter around the object you're protecting, adjusting them until the laser hits the photocell.

Step 12: Test the system

Now break the beam to test the system...
And get ready to confront the perpetrator with your irrefutable evidence.

Thanks for watching How To Build a Laser Security System! If you enjoyed this video subscribe to the Howcast YouTube channel! http://www.youtube.com/subscription_center?add_user=howcast

Category:

Science & Technology

Tags:

• howcast
• how-to
• tech
• laser
• security
• experiment
• science

[XillegaltoastX]

Oh yeah 6 moped mirrors duct taped around a wallet with a soap container and a laser pointer just chilling on your desk aren't conspicuous.

[Instinct869]

Thumbs up if you saw this on related videos, guessed you weren't going to be able to make this (and guessed right), but you were curious too see how to make it.

[onlinecrunch]

@pipman10234 i know right!!!



[pipman10234]

why watch this when you can watch kipkay!

[itskelly98]

Or you could..just...put a camera..in a corner..and film it..?

[123themeta]

aha! now i have a pic of your hand! its only a matter of time now

[BranmanR]

damn, ive seemed to have misplaced my 220 ohm resisitor.

[xAlexanderNguyen]

Alien hand syndrome?

[piraat6666]

I would use taser instead of camera

[jaytigerdtg]

is voltage regulator really need in that thing or not? if yes can you explain why?

and what kind of voltage relay you use, anything to identify what kind of voltage relay did you use

[555bigman555]

how u can see how is that ,, ho is stealing u'r stuff? you can see only his hand.

[limowm]

Why not add a shotgun, loaded with oobuckshot?