Mobile phones are banned (if not explicitly, at least at the level of common sense) in quiet public places such as restaurants, theaters, cinemas and churches. What if people do not understand the good word and close their phones? Use a jamming device.

Many people can not come off the phone in those places and even use it extensively. If they would be limited to SMS it should be acceptable, but they don't even bother to pass it on silent mode. Jamming devices are widely used in Romania, but in other countries they are popular and we ensure silence in many places.

Jamming devices are devices that block or interrupt radio signals emitted by the phones. These devices have high power and manage to cancel the signal. They are effective even against dual-SIM mobile handset, it "tricked" the area where there is no coverage of any mobile operator. There Jammer, a sophisticated devices that can signal to cancel even Triple-card phones, which are connected simultaneously to the three mobile networks.



Operation frequencies jamming devices are easy to set up and function properly depending on your choice of these frequencies. Mobile-phone frequencies 900 and 1800 MHz to 1900 MHz for Europe and Asia and USA. Distance interference is influenced by the obstacles encountered in the way radio waves, such as walls or hills. Poor equipment interference can do their job within a radius of 9 m in a building, while in an open space can even cover a football field. There are no devices currently succeeding phone jamming signals over a distance greater than 1.6 km.

A jamming contains device electronically speaking, consists of a hub device, transmitting antenna, and power supply circuits. The front panel is usually a potentiometer, where you can choose the frequency of work. Wireless devices and less power, are power by a battery. Powerful devices are powered directly from mains.

Proved useful in avoiding bombings as most bombs were triggered by mobile phones they have been used to shift the official columns to prevent bomb attacks on important persons in the world. Their use has been successful even to jam the communications between criminals and terrorists, in case of attacks. The devices are used in areas with high risk of explosion, because a cell phone can trigger such an event in a high risk area.



Laws concerning the use of jamming devices There are few countries where the use of jamming is perfectly legal. In most countries like the U.S., Britain and Australia, the jamming of mobile phones is prohibited. In the U.S., the law says that such devices may be used only with special permit and license. The sale of these devices it not allowed. Those who do not comply with the regulations are likely to receive a $ 11,000 fine and remain without a jamming device. Sometimes, they go to prison.

Other countries, like France, have such equipment in cinemas, concert halls and other public places. In India they are used in some prisons and parliament. If you are a student in Italy, it might surprise you that during your exam you cannot use your phone as rectors of universities to the idea of blocking the signal of phones so nobody could use the to cheat.