First we have to understand what is a recording blocker, what is a signal blocker? Recording blockers are used to interfere with the recording of mobile phones, voice recorders and other recording devices, by issuing random ultrasonic noise, so that the recorded sound doped with noise, can not hear the content of the conversation. The signal blocker is used to block mobile phone signals, shielding mobile phone 2/3/4G signals and WiFi signals, so that mobile phones can not make calls, can not access the Internet.
Both belong to the shield, but the principle is not the same.
The signal blocker can be shielded, mobile phone signals, WIFI signals, walkie-talkie signals, GPS signals, remote control signals, etc. belong to a kind of signal, this kind of blocker is through its own frequency signal to interfere with the normal signal reception.
Principle of signal blocker
Within a certain frequency range, the mobile phone and the base station are connected by radio waves to complete the transmission of data and sound at a certain baud rate and modulation. The mask scans from the low frequency of the forward channel to the high frequency at a certain speed during operation. The scanning speed can form garbled interference in the received message signal of the mobile phone, and the mobile phone cannot detect the normal data sent from the base station, so that the mobile phone cannot establish a connection with the base station, and achieve the purpose of shielding the mobile phone signal, and the mobile phone shows the phenomenon of searching the network, no signal, and no service system.
The principle of a recording blocker
By sending out ultrasonic waves with random noise that cannot be heard by human ears, when digital devices such as mobile phones record, these noises are recorded together with the sound of normal conversation into the digital devices, making the recorded audio invalid, and the audio information in the recorded video also has the same interference effect, because the noise with ultrasonic noise is generated randomly and cannot be restored. Therefore, the audio after interference can not be restored.
