Muting of audio circuits when received signal levels fall below a pre-determined value. With
carrier squelch, all channel activity that exceeds the preset squelch level can be heard.
Synchronous Serial Interface (SSI)
DSP interface to peripherals that consists of a clock signal line, a frame synchronization signal
line, and a data line.
Standby
An operating condition whereby the radio’s speaker is muted but still continues to receive data.
Status Calls
Pre-defined text messages that allow the user to send a conditional message without talking.
Tactical/non-revert
The user will talk on the channel that was selected before the radio entered the emergency state.
TalkAround
Bypassing a repeater and talking directly to another unit for local unit-to-unit communications.
Talkgroup
An organization or group of radio users who communicate with each other using the same
communications path.
TMS
Text Messaging Service.
Trunking
The automatic sharing of communications paths between a large number of users. Allows users
to share a smaller number of frequencies because a repeater or communications path is
assigned to a talkgroup for the duration of a conversation.
Trunking Priority Monitor scan list
A scan list that includes talkgroups that are all from the same trunking system.
USK
Unique shadow key.
UTC
Coordinated Universal Time. The international time standard (formerly Greenwich Mean Time, or
GMT). Zero hours UTC is midnight in Greenwich, England, which is located at 0 degrees
longitude. Everything east of Greenwich (up to 180 degrees) is later in time; everything west is
earlier. There are 42 time authorities around the world that are constantly synchronizing with
each other. Abbreviated as UTC (English backronym = Universal Time, Coordinated), it is also
known as Zulu (Z) Time.
VRS
Vehicular Repeater System.
MN003110A01-AK
Glossary
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