In the past, wireless signal jammers were used in examination rooms. The method of shielding mobile phone signals was to transmit signals similar to base stations, covering the signals of base stations at close range, so that mobile phones could not find base station signals. Even if there is no signal shielding function for mobile phones, other safer and more environmentally friendly detection methods may be used. According to the shape of the shield, mobile phone signal shielding can be divided into omnidirectional and directional types. The shape of the omnidirectional type is like an olive, and the shape of the directional type is fan-shaped, so the shielding range of the omnidirectional type is larger than that of the directional type.

The jammer emits electromagnetic waves of a specific frequency to suppress mobile signals. If the power of the shield is greater than the local mobile signal, the mobile phone will have no signal; if the power of the shield is less than the power of the local mobile signal, the mobile phone will have a signal.  cell phone jammer

Matters needing attention in use:

1. Install the antenna according to the corresponding mark on the host, and then power on the host (it is strictly forbidden to turn on the power without connecting the antenna).

2. The transmitting antenna of the shield body adopts an omnidirectional antenna. The effective coverage area is an area that gradually weakens with the antenna as the center. When using it, pay attention to the correct selection of the placement and angle of the antenna to avoid shielding dead angles.
3. The wireless signal jammer should be placed in a well-ventilated place, and the antenna should be installed as far away from large objects, strong heat sources and strong electromagnetic sources as possible to ensure the shielding effect and long-term stable operation.