A pager (also known as a beeper) is a wireless telecommunications device that receives and displays alphanumeric messages and/or receives and announces voice messages. Pagers operate as part of a paging system which includes one or more fixed transmitters, as well as a number of pagers carried by mobile users. These systems can range from a restaurant system with a single low-power transmitter, to a nationwide system with thousands of high-power base stations.
It can vibrate, beep or flash to discreetly gain the attention. There are links which includes:
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