The interference range of telephone jammers varies according to the power of products. The interference radius of high-power signal jamming equipment used in prisons can reach hundreds of meters, while the interference radius of low-power jamming equipment suitable for use in examination halls and conference rooms is generally between 1 and 10 meters, mainly depending on the strength of nearby signal base stations.

The high-power signal jamming equipment has a very strong jamming ability and is suitable for special occasions such as prisons and detention centers. However, because of its strong interference ability, if it is near a residential area, it will inevitably affect the normal mobile phone call needs of the nearby people. Therefore, high-power signal jamming equipment is generally used in relatively open places far from residential areas. On the contrary, the interference radius of low-power signal jamming equipment is between 1-10m, because the interference effect of the jammer mainly depends on the signal strength of the place of use. If multiple signal base stations are set up in a school campus, and the reception level of mobile phones is too large, the actual interference of the jammer will be greatly shortened. If there is no base station in the campus, the interference effect of the telephone jammer will be very good. There is no problem interfering with a distance of 10 meters. It is enough to put one jammer in one examination room.

As more and more mobile phone signal transmitting base stations are installed in cities, the overall signal strength is getting better and better. So that the original telephone jammer can achieve the interference range with a radius of 10 meters. Now, the interference effect of the same machine may be reduced.