How to make a burglar alarm with his own hands
How to secure their own apartment or house from unwanted intrusion guests? At first glance, this may seem a rather difficult task, as you need a modern expensive equipment to implement the ideas. However, it is really simple to make signaling with his hands.
There is such a small thing as a sound system, in other words, a piezoelectric switch. This small device weighs only 80 grams, its structure, there is absolutely nothing complicated, so it can be applied in the protection of their possessions.
The noise level, which makes this device is 110 decibels. For those who do not know, these figures are the noise of the engine jet aircraft. Simply put, it is very loud. The principle of the security alarm system is as follows: the limit switch is installed at the front door, it will be either a mechanical or magnetic, but it is necessary that there was a well-closed contact. This element will serve as a siren, which responds to opening the door.
Outdoor or indoor siren is installed, it is best to place it in a protective cage. You also need to go through the elements of the two-wire cable connections. Power is connected to the step-down transformer 220 to 12 volts. With the door closed normally closed contact switch operates so that current flows through it, which powers the device. The signal is in such a position is not supplied, so the horn is not working.
When you open the door there is an open circuit, which powers the device, so the contacts of the signaling power. The device starts to emit loud noises. If a thief sneaks into the house, where a very loud alarm sounds, it will attract the attention of neighbors and others that are very scare enemies. If no one is around, the siren sound will still not allow attackers to long in the room, because the sound is almost unbearable and they will quickly leave the building.
So it looks like the simplest security system. Even if the compromised integrity of the cable that goes from the end relay switch, the system will still work. If there is a power outage in the entire building, this burglar alarm will be useless.
Of course, this system can not be considered fully effective, but it is ideal for a small holiday home. In addition, the installation does not require any specific skills, you just know the basic things and be able to apply them in practice.