Motorola EP450 service manual Glossary of Terms, Term Definition

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 sub-
	scriber unit to the central control unit.
LH DATA	Longhorn Data: a bidirectional 0-5V, RS-232 line protocol that uses the micro-
	controller’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 con-
	nection 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.