Super Easy Laser Trip Wire / Alarm / Coilgun Switching

Introduction: Super Easy Laser Trip Wire / Alarm / Coilgun Switching

Switch your coilgun coils, protect your home or hook it up to a counter.

The most simple lightgate out there, yet very reliable!

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Step 1: All Parts You Need:

- 9V clip

- 10k resistor 0.25W (to transistor)

- 300 Ohm resistor (for a blue LED)

- Photo-transistor SFH 309

- BUZ 11 transistor

- Small SCR

- Slide switch (main switch)

- Momentary switch (reset button)

- Wire

- Board

- Solder

- Soldering iron

- Laser pointer (cheap key chain laser will do)

Step 2: The Steps:

If you are unexperienced with electronics, just copy the schematic 1:1

and put it on a board.

Hook up the laser to a separated battery, make it hit the phototransistor,

then switch on the board. Break the beam and the LED should light up.

EASY was not a lie, thats it. You can now switch a multistage coilgun with it,

protect your room or door.

Step 3: Instructional Video

Bit of explanation and demonstrating the set up.

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    2 Discussions

    DIY Hacks and How Tos

    This is great. These make excellent DIY security systems.


    Reply 3 years ago