This DIY Sonic Tripwire Alarm Is a Loud, Perfect Early Warning System
Worried that someone might invade your evil lair? This DIY audible alarm is easy to assemble, loud enough and perfect for simple hide-and-seek games or creating a perimeter around anything you want to keep.
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The video above shows you basically how it’s all done, and it’s a great way to see it in action. In short, all you need is a battery operated alarm clock (you will need to take care of choosing the right one for the project), some fishing wire, a plastic or wooden clothespin, a hex key, some foil, an old gift card, some wire and some duct tape.
You will need to check out the complete step-by-step guide (link below), but essentially you are creating a chain between the foil-wrapped ends of the clothespin and the watch through the battery compartment. When the clothespin is closed, the circuit closes and an alarm is triggered. When the pins of the pin do not connect, the circuit is open and everything is in order. You will use the piece of this gift card tied to the fishing wire to keep the prongs apart. When someone walks by, hooks on the wire and yanks out the wedge of cards, an alarm goes off, informing you that there is an intruder.
It’s simple, it’s really easy to find standard parts, and it works like a charm without being overly complex. Watch the video above and then check out the step-by-step Instructables tutorial below.
Tripwire Audible Alarm | Instructables