Kantronics KPC-9612 Plus, Руководство пользователя

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A numeric page is initiated at a touch-tone phone. To page your spouse, for ex-
ample, you’d dial a phone number assigned to the pager, wait for the automated
voice prompt from the paging terminal - “please enter a number followed by the
# sign,” enter the phone number where you’d like to be reached, and hang up.
The paging terminal, in turn, “makes up” the paging message for your spouse, in-
cluding your message and the address of the pager (ID), adds it to a stack of
pages to be sent, and transfers these pages within a few minutes to a bank of
transmitters. Once transmitted, at the radio frequency assigned to your paging
service, your spouse’s pager beeps - after recognizing its unique ID - and stores
the message sent.
As you can see, the system is similar to many other systems we use. In collecting
paging messages, the paging terminal simply prompts the caller - as a telephone
answering device (TAD) would - to leave a message. Your touch-tone phone and
the telephone company’s equipment does the rest. The paging terminal has other
jobs too. It must keep track of pairs of phone numbers and pager IDs, keep a re-
cord of messages sent, control the transmitters spread out across the city, and
manage the paging system as a whole. With inter-city paging, so-called wide
area paging, paging network controllers handle the job of exchanging pages be-
tween cities and systems, often using the comercial Telecator Network Paging
Protocol (TNPP) to accomplish their task.
The job of the transmitters is basic. They transmit a batch of pages upon demand,
and may transmit each page on all transmitters at once, called simulcasting. The
messages are sent at the radio frequency (RF) assigned to the paging service by
the FCC using frequency modulation (FM). For numeric and alphanumeric pag-
ers, the digital information is sent with a frequency-shift-keying (FSK) modula-
tion format. To send ones and zeroes, the frequency of the transmitter signal, the
carrier, is shifted (deviated) up or down in frequency by 4.5 kHz.
The pagers complete the system. They wake up about once per second to look for
a paging signal addressed specifically for them. If a pager sees its ID in any of
the pages being transmitted, it picks out that page, beeps (or vibrates) the person
carrying or wearing it, and stores the message (if a numeric or alphanumeric
pager). The person carrying the pager is then free to display the message on the
LCD.
Modes of Operation Paging
User’s Guide 144 KPC-9612 Plus v 8.2