The coverage of the jammer depends on many factors, such as the transmitting power of the cell phone jammer, the type of antenna used (directional or non-directional), the location of the device, the distance from the interference area to the cellular relay, the presence of moving obstacles, etc. . The maximum distance intercepted by cell phone scrambler ranges from a few meters with less power to dozens of kilometers of military phone jammers for military use.
In the affected area, if the jammera equipment used blocks all calls indefinitely, it may bring some negative effects, so be careful not to use it for illegal purposes. It is not difficult to find a mail order model on the Internet today. There are portable cell phone scrambler for cars cost only tens of dollars, and high-power interference equipment used to prevent and control drones cost thousands of dollars.
