雷霆网络区域校准Electric wave

The app allows your phone to display accurate radio signals, you can set the area according to your needs, and it has a good auxiliary function for the calibration operation.

Usage and precautions:
1 There are no electrical appliances within 10 meters of the surrounding area, including refrigerators, washing machines, computers, microwave ovens, televisions, and air conditioners.
2 [Important] Please insert the earphones and adjust the volume of the phone to the maximum, put the sounding part of the earphones close to the watch, and wrap the earphones clockwise with the watch.
3 Please ensure that the surrounding area is quiet and no noise.

Principle of wave generation: The sound card can only output up to 22 kilohertz of sound, how can it send out a 68.5 kilohertz wave signal? The audio signal played by the computer is actually exquisite. We chose the 5th frequency division of 68.5 kHz, 13.7 kHz, and used this as the carrier to load the BPC code on it. The sound of the earphone is realized by the changing magnetic field produced by the coil to push the diaphragm, so while the audible sound is emitted, it also emits inaudible electromagnetic waves. When we turn the output volume to the maximum, the non-linear effect of the headset becomes significant. The frequency components include not only the fundamental frequency component (13.7 kHz) but also the frequency component, which also contains the 5 octave signal of 13.7 kHz and 68.5 kilohertz. Hz, which is the carrier frequency of the BPC.