The vast majority of signal jammer  adopt a relatively enclosed housing design, because manufacturers consider various application environments, such as indoor, outdoor, or mobile use, for easy transfer. The accompanying antennas are also equipped with built-in antennas. The method of designing an external antenna many years ago, which involves directly screwing the antenna onto the body of a signal jammer, is now rare. However, manufacturers who still use the external antenna method will explain to customers from this perspective that the built-in antenna, due to the blocking and attenuation effects of the chassis, will affect the signal transmission of the signal jammer, thereby reducing the effectiveness of the signal jammer. So, is it correct to say that the built-in effect of the antenna is not good?

This statement may seem reasonable, but it is actually incorrect. The signal jammer emits a signal that blocks the phone through the antenna. From the type of signal, it is actually a type of radio wave. As is well known, the transmission characteristics of radio waves are different from the transmission of light. When light encounters obstacles from objects, it will be interrupted, or refracted and reflected. After the radio wave is emitted through the antenna, it will directly penetrate or detour through obstacles. Its transmission characteristics are somewhat similar to the commonly known sound wave transmission, and as the transmission distance increases, its signal strength gradually weakens.

The signal jammer using a built-in antenna is usually made of ABS plastic or customized transparent material. The wireless signal of the signal jammer can directly penetrate the shell, and the signal attenuation generated by the shell can be almost negligible. So there is no need to worry about reducing the interference effect of the phone due to the built-in antenna.