When the cell phone jammer is in active mode and makes the phone talk to it instead of the real cell phone tower, it will prevent these phones from sending real calls or text messages. You may think that your calls and text messages are not answered, and the only hint is that your phone shows that it is using 2G instead of 4G or LTE. When a cell phone jammer is in passive mode, it can receive and analyze cell phone signals, or it can be used to block these phones. Leave the street and enter a local business or someone’s home to avoid making a phone call, avoid cell phone interference, and may not be able to work. Most of these devices can pass through the walls in their surveillance area. When you protest in New York City under the close watch of the New York City Police Department and the FBI, you can be sure that they will use the most advanced versions of these devices-including possibly listening to Triggerfish live conversations. According to the American Civil Liberties Union, not only New York law enforcement agencies, but other state law enforcement agencies are using cell phone jammer technology.
This seems to be about maintaining the authority of the school, rather than prohibiting the use of mobile phones. In that respect… it is completely counterproductive. Many schools effectively banned the use of mobile phones without resorting to technical restrictions (I attended such high schools). The principal should explain to students and teachers why mobile phones are a problem, and set some reasonable usage guidelines and reasonable consequences for policy violations. It may help establish the authority of the principal and win the respect of the students without having to install illegal equipment and be forced to backtrack. According to a report by “United News”, government officials said that the broadcast appeared to have started from various places along the border a month ago, but the signal from a mobile phone jammer from North Korea on Thursday was the largest.