The actual range of the wireless jammer depends on its performance and the local environment, including hills or walls of buildings that block the jamming signal. Low power jammers can block calls within 30 feet. Higher performance units create a unit with no surface that is the size of a soccer field. A device used by law enforcement agencies can shut down services 1 mile from the equipment.
The jamming device overloads the mobile phone by sending signals at the same frequency and power enough so that the two signals collide and cancel each other out. Cell phones are designed to increase performance when they encounter low-level interference. Therefore, the jammer must recognize and adjust the increase in performance of the cell phone.
To interfere with the phone, all you need is a device transmitting on the correct frequency. Although different cellular systems process signals differently, all cellular networks use radio signals that can be interrupted. GSM, used in digital cellular and PCS-based systems, operates in the 900 MHz and 1800 MHz frequency bands in Europe and Asia, and the 1900 MHz frequency band (sometimes referred to as 1.9 GHz) in the United States. The jammer can transmit on any frequency and is effective for AMPS, CDMA, TDMA, GSM, PCS, DCS, iDEN and Nextel systems. Old-fashioned analog telephones are just as susceptible to interference as today's digital devices.
If you pay attention to the wifi jammer update, choosing a cell phone blocker is an issue that requires attention. The cell phone jammer is a device specially designed for entry into the test room. Using the 7-channel design. Solve the transfer problem completely. It hides the problem of a bad signal. We fundamentally solve the phenomenon of signal instability. With this product, you don't have to worry about the adverse effects of cell phone signals on those around you. It has a built-in antenna. The jammer can also be placed anywhere in the restricted area