Pager alarm Other paging protocols used in the VHF, 400MHz UHF, and 900MHz bands include POCSAG and ERMES. Even more recent models included the ability to send messages in a two-way fashion and even included the ability to send and receive email. Note that the idiomatic sound heard in popular media (movies and television programs) as "pager going off" (a series of two short beeps interrupted by a slightly longer pause) is actually the "pager power-up verification beep" sequence, perhaps because it was easier to generate that tone on demand (simply flip the power switch on). Many paging work operators now allow numeric and textual pages to be submitted to the paging works via email. For this reason, older forms of message submission retain their usefulness for disseminating highly-important alerts to users such as emergency services personnel. For example, they are required to be used by UK lifeboat men and retained firefighters. Later pagers used digital messages, first numeric and later alphanumeric, to provide the recipient with more rmation. Commercial paging transmitters typically radiate 1000 watts of effective power, resulting in a much wider coverage area per tower than a mobile phone transmitter, which typically radiates in the neighborhood of 0.6 Watt per channel. Thus, if a pager has nationwide service, a message sent to it could be intercepted by criminals or law enforcement agencies anywhere within the nationwide service area. Even more recent models included the ability to send messages in a two-way fashion and even included the ability to send and receive email. Pager alarm. This can result in pager messages being delayed or lost. Pagers usually have very simple ring tones and some include a vibrating alert. For example, they are required to be used by UK lifeboat men and retained firefighters. The slower POCSAG on-air protocol is still used for some pagers in the United States and probably in other countries. |
