Laser alarm
Robbers and other criminals are becoming smarter every day. Many people, like me, do not have an alarm system. And if you are not at home, then your valuables become easy prey for a criminal. You've probably heard about such an invention as lasers. If you touch them, the siren will sound. But they are very expensive. Therefore, I offer you this video instruction, which will show you how to make such a laser at home, spending no more than 1000 rubles.
Similar master classes
Particularly interesting
Cable antenna for digital TV in 5 minutes
A selection of simple and effective schemes.
Three-phase voltage from single-phase in 5 minutes
Starting a three-phase motor from a single-phase network without a capacitor
Eternal flashlight without batteries
How to make an inexpensive but very powerful LED lamp
Comments (2)