The installation of equipment to prevent prison calls meets very strict standards in order to avoid interference with communication networks outside the prison. signal jammer are designed to disable phones in certain areas. They block reception and mobile radio waves, which will prevent communication between mobile devices and relay antennas. But smartphones are the real killers. Recent statistics on the use of mobile phones while driving indicate that more than 20% of fatal car accidents are caused by inappropriate use of mobile phones. Hundreds of people are killed and injured every day around the world due to the use of mobile phones while driving. Cell phone jammers are only a good way to force the prohibition of cell phone use while driving.

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gps jammer are small and useful devices that are definitely useful to many people. Its main purpose is to block signals from GPS tracking equipment. If you are concerned that someone is following you or you just want to use a GPS blocker when you need it, there are a few things you should know about these devices. One of the main things you should check when purchasing a GPS blocker is how often it works. Generally, GPS tracking devices can operate in the GPS frequency band L1 or sometimes at other frequencies, so it is important to know their frequency.

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An interfering device is a device that emits radio waves, and its frequency band is the same as that used by a mobile phone. Therefore, it is not possible to use a mobile phone or the like where the device is installed. After the signal shielding device is installed, the mobile phone will not be in service and you will not be able to make or receive calls.Due to the rapid development of electronic communication means, cheating seems to be more and more diversified. The use of mobile phones or small headphones to cheat and passed in the test, and this cheating phenomenon is very common.

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