The interference range of the jammer varies according to the product power. The interference radius of the high-power Signal Jammer used in the prison can reach hundreds of meters, while the interference radius of the low-power jammer suitable for the examination room and conference room is generally between 1-10 meters, depending on the strength of the nearby signal base station.

        

The shielding ability of high-power equipment (hundreds of W or even more than 1000W) is very strong, which is suitable for special occasions such as prisons and detention centers. However, because of its strong shielding ability, if it is close to residential areas, it will inevitably affect the normal mobile phone call needs of nearby people. Therefore, high-power equipment is generally used in relatively open and far away from residential areas.
The shielding radius of low-power Signal Jammer (generally 12w-20w) is between 1-10m. The instructions of some products claim that it is between 1-20m and 1-30m. In fact, the upper limit here is difficult to reach.
This is 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 the campus of a school, and the mobile phone reception level is ≥ - 70dBm, the actual shielding of the Signal Jammer will be greatly shortened, and may only be shielded for a distance of 2 or 3 meters.
If there is no base station in the campus and the receiving level of mobile phone is ≥ - 90dbm, the Signal Jammer will be very good. The shielding distance of 10m is no problem. It is enough to put a shield in one examination room. Finally, it should be noted that the shielding range of the shield may change over time.
As more and more mobile signal transmitting base stations are installed in the city, the overall signal strength is getting better and better. Originally, the Signal Jammer could realize the shielding range with a radius of 10 meters. Now, for the same machine, the shielding radius may be reduced to 5 meters - this is not a failure, but the surrounding signal environment has changed.