Motorola ASTRO XTL 2500, Руководство по установке

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October 12, 2005 HLN6923A
Glossary-6
paging One-way communication that alerts the receiver to retrieve a message.
Patriot IC A dual-core processor that contains an MCU and a DSP in one IC
package.
PC Board Printed Circuit Board. Also referred to as a PCB.
phase-locked loop A circuit in which an oscillator is kept in phase with a reference, usually
after passing through a frequency divider.
PL See private-line tone squelch.
PLL See phase-locked loop.
private-line tone
squelch A continuous sub-audible tone that is transmitted along with the carrier.
See also DPL.
Programmable
Read-Only Memory A memory chip on which data can be written only once. Once data has
been written onto a PROM, it remains there forever.
programming cable A cable that allows the CPS to communicate directly with the radio
using RS232.
Project 25 See APCO 25.
PROM See Programmable Read-Only Memory.
PTT See Push-to-Talk.
Push-to-Talk The switch or button usually located on the left side of the radio which,
when pressed, causes the radio to transmit. When the PTT is released,
the unit returns to receive operation.
radio frequency The portion of the electromagnetic spectrum between audio sound and
infrared light (approximately 10 kHz to 10 GHz).
radio frequency
power amplifier Amplifier having one or more active devices to amplify radio signals.
Radio Interface Box Not used with XTL 5000. The radio communicates directly to the
computer via a single programming cable.
See programming cable.
Radio Service
Software Not used with XTL 5000. See Customer Programming Software.
RAM See random access memory.
random access
memory A type of computer memory that can be accessed randomly; that is, any
byte of memory can be accessed without touching the preceding bytes.
read-only memory A type of computer memory on which data has been prerecorded. Once
data has been written onto a ROM chip, it cannot be removed and can
only be read.
Term Definition