Motorola APX 4000, Basic Service Manual

Page: 509 / 526

Glossary Glossary
This glossary contains an alphabetical listing of terms and their definitions that are applicable to
ASTRO portable and mobile subscriber radio products.
Term Definition
A/D See analog-to-digital conversion.
Abacus IC A custom integrated circuit providing a digital receiver intermediate
frequency (IF) backend.
active channel A channel that has traffic on it.
ACK Acknowledgment of communication.
ADC See analog-to-digital converter.
ADDAG See Analog-to-Digital, Digital-to-Analog and Glue.
analog Refers to a continuously variable signal or a circuit or device designed
to handle such signals.
See also digital.
Analog-to-Digital,
Digital-to-Analog
and Glue An integrated circuit designed to be an interface between the radio’s
DSP, which is digital, and the analog transmitter and receiver ICs.
analog-to-digital
conversion Conversion of an instantaneous dc voltage level to a corresponding
digital value.
See also D/A.
analog-to-digital
converter A device that converts analog signals into digital data. See also DAC.
ASTRO 25 trunking Motorola standard for wireless digital trunked communications.
ASTRO conventional Motorola standard for wireless analog or digital conventional
communications.
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.
autoscan A feature that allows the radio to automatically scan the members of a
scan list.
band Frequencies allowed for a specific purpose.
BGA See ball grid array.
ball grid array A type of IC package characterized by solder balls arranged in a grid
that are located on the underside of the package.
Call Alert Privately paging an individual by sending an audible tone.