ZETRON 640 DAPT XTRA, Руководство по установке и ремонту

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Glossar
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Term Definition
Channel
An electronics communications path. A narrow band of frequencies
(assigned by the FCC) that a radio system must operate within to
avoid interference with other adjacent channels.
Circuit
A pathway for electrical signals.
Class of Service
(COS)
A set of operating parameters that defines certain paging subscribers.
The class of service identifies settings like paging coverage zones,
voice and display page limits, caller security codes, etc.
Clear to Send (CTS)
A data input that determines when the line is clear (not busy) for
transmission of information.
Colocated
Refers to two or more pieces of paging equipment that are located at
the same site. This type of system allows for direct cable hookup,
rather than modem or RF-type connections.
COM LED
A light on the front panel of the paging terminal indicating when a
local serial communications link has been established between the
Model 640 and a computer or dumb terminal. This LED flashes
rapidly during data transfers and flashes intermittently when a link is
present but no data is being transferred.
COM Port
A serial communications connector. On the Model 640, the COM port
is used for ZLINK connection to the PC’s own COM port. Most COM
ports follow the RS-232 conventions for serial interface.
Coverage
The useable radio time and geographic area of a system.
CPU (Central
Processing Unit)
The “brains” of a computer or paging terminal. The CPU controls data
acquisition, processing, and transfer to other peripheral cards in the
hardware.
CRC (Cyclical
Redundancy Check)
An error-detection process used in the TNPP protocol. The CRC
computes a general polynomial based on the entire TNPP binary data
packet. In the protocol packet structure, the CRC occupies the last 2
bytes of data.
Clear to Send (CTS)
A data input that indicates when it is okay to send data to the radio
station equipment. This signal is used in cross-busy applications to
ensure that two encoders do not attempt to key up simultaneously.
Current
The flow of electricity through a circuit (measured in amperes).
Database
A software program that stores many records of information. Each
record shares the same parameters (with different settings). A database
can be sorted by each of its characteristics. In the Model 640, the data-
bases store valuable system information including subscriber records,
transmitter settings, and telephone trunk descriptions.
Data Terminal Ready
(DTR)
A data output that determines when the receiving party is set to accept
information.