Motorola PR860 Basic Service Manual page 60

Glossary-2
MRTI
MSK
OMPAC
OSW
PassPort™
PC Board
PL
PLL
PPM
PTT
RAM
Registers
Repeater
RESET
RF PA
RIB
ROM
RSSI
RPT/TA
Softpot
Software
SPI (clock and data
lines)
Squelch
Motorola Radio-Telephone Interconnect: a system that provides a repeater
connection to the Public Switched Telephone Network (PSTN). The MRTI
allows the radio to access the telephone network when the proper access code
is received.
Minimum-Shift Keying.
Over-Molded Pad-Array Carrier: a Motorola custom package, distinguished by
the presence of solder balls on the bottom pads.
Outbound Signalling Word: data transmitted on the control channel from the
central controller to the subscriber unit.
Enhanced trunking protocol developed by Trident Micro Systems that links
wide area dispatch networking.
Printed Circuit Board.
Private-Line® tone squelch: a continuous sub-audible tone that is transmitted
along with the carrier.
Phase-Locked Loop: a circuit in which an oscillator is kept in phase with a
reference, usually after passing through a frequency divider.
Parts Per Million.
Push-To-Talk: the switch located on the left side of the radio which, when
pressed, causes the radio to transmit.
Random Access Memory: the radio's RAM is loaded with a copy of the
EEPROM data.
Short-term data-storage circuits within the microcontroller.
Remote transmit/receive facility that retransmits received signals to improve
communications coverage.
Reset line: an input to the microcontroller that restarts execution.
Radio Frequency Power Amplifier.
Radio Interface Box.
Read Only Memory.
Received Signal-Strength Indicator: a dc voltage proportional to the received
RF signal strength.
Repeater/Talk-Around.
Software Potentiometer: a computer-adjustable electronic attenuator.
Computer programs, procedures, rules, documentation, and data pertaining to
the operation of a system.
Serial Peripheral Interface: how the microcontroller communicates to modules
and ICs through the CLOCK and DATA lines.
Muting of audio circuits when received signal levels fall below a pre-determined
value.