What is a BB machine?

BB machine, also known as "pager", is the receiver of called user in wireless paging system. 1948, Bell Laboratories developed the world's first pager, named BellBoy.

BB machine 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 is small in size, light in weight, low in price and low in 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.

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History of BB Machine in China

1983, Shanghai opened the first paging station in China, and BP machine entered China. In the late 1980s, pagers began to appear in China. With the maturity of science and technology and the increase of social demand, paging stations have sprung up everywhere since 1990, and the prosperity of paging market has made the competition between paging stations increasingly fierce.

1993, 1994, mobile phones began to appear slowly. 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 gradually faded out of the stage in China.

BB machine operation series mode

There are two ways of BB machine: manual tandem and automatic tandem, and the corresponding paging stations are called manual paging stations and automatic paging stations. Manual paging stations need manual operation to encode these messages and send signals through the transmitter. The automatic paging station automatically finds out the phone number of the pager according to the line number of the incoming call and sends it out at the same time, so that the called party can know which phone is calling.

Commonly used pagers are divided into two categories: digital pagers and Chinese pagers. Digital pagers are small, cheap and practical. Chinese pager directly displays Chinese characters, and the information is easy to identify.

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