The BB machine is the BP machine, and the English name is pager-beeper. Chinese commonly known as pagers, pagers and so on. Sometimes the abbreviation is BP, or BB, nothing, they all mean the same thing. Just like cell phones used to be called cell phones.

BB machine is called user receiver. It consists of superheterodyne receiver, decoder, controller and display.

It selects the useful signal to be received from the paging signal and interference transmitted by the base station, restores it to the original baseband signal of the pager, and generates audio (or vibration) and displays digital (or letters and Chinese characters) information.

BB machine performance:

Small size, light weight, low price and low power consumption. Pagers can receive digital and simple phrase information, Chinese characters, documents, notices, stock market and other extensive services, and can even be used as terminals for telegrams and data networks. The sensitivity of Chinese character display or digital display pager is better than 10μV/m or 5 μ v/m; The adjacent channel selectivity is better than 60dB(VHF band); Digital display bit length is not less than 12 bits; Mean time between failure is not less than 30,000 hours.

Some paging devices are also connected to the telephone at home. If no one answers the phone after a certain period of time, the call will be automatically transferred to the paging station. Pagers are cheap and easy to use, which makes them widely used in various industries.

From the second half of 1995, the paging service gradually fell under the strong offensive of mobile phones, and the number of paging users began to stop increasing. 1996 began to decline, the number of users decreased, and the number of paging stations also dropped sharply.

After 2005, pagers faded out of the stage in China.

References:

Baidu encyclopedia-pager