Motorola Commercial Series, Basic Service Manual

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Glossary of Terms
Term Definition
ALC Automatic Level Control: a circuit in the transmit RF path that controls RF power
amplifier output, provides leveling over frequency and voltage, and protects
against high VSWR (voltage standing wave ratio).
ASFIC Audio Signalling Filter Integrated Circuit
BKC Bad Key Chirp
CD Compact Disk
CMP Compression
CPS Customer Programming Software
CSQ Carrier Squelch
DTMF Dual-Tone Multifrequency
DPL Digital Private-Line™
EEPROM Electronically Erasable/Programmable Read-Only Memory: used by the radio to
store its personality
Firmware Software, or a software/hardware combination of computer programs and data,
with a fixed logic configuration stores in a read-only memory. Information cannot
be altered or reprogrammed.
FGU Frequency Generation Unit
GaAs Gallium Arsenide: a type of crystalline material used in some semiconductors.
GKC Good Key Chirp
ISW Inbound Signalling Word: data transmitted on the control channel from a
subscriber unit to the central control unit.
LH DATA Longhorn Data: a bidirectional 0-5V, RS-232 line protocol that uses the
microcontroller’s integrated RS-232 asynchronous serial communications
interface (SCI) peripheral.
LLE Low Level Expander: slight amount of volume expansion; used to improve the
signal to noise ratio.
MCU Micro Controller Unit
MRTI 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.
OMPAC Over-Molded Pad-Array Carrier: a Motorola custom package, distinguished by
the presence of solder balls on the bottom pads.
PC Board Printed Circuit Board
PL Private-Line® tone squelch: a continuous sub-audible tone that is transmitted
along with the carrier.