Motorola XTS 2500 Basic Service Manual page 84

Glossary
PTT
Registers
Repeater
RESET
RF PA
RPT/TA
RX DATA
Signal Qualifier Mode
SCI IN
Softpot
Software
SPI
Squelch
SRAM
Standby Mode
System Select
TOT
TSOP
UART
µC
VCO
Vocoder
VSWR
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Push-To-Talk; the switch located on the left side of the radio which, when pressed, causes the
radio to transmit.
Short-term data-storage circuits within the microcontrol unit or programmable logic IC.
Remote transmit/receive facility that re-transmits received signals in order to improve
communications coverage.
Reset line; an input to the microcontroller that restarts execution.
Radio Frequency Power Amplifier
RePeaTer/Talk-Around
Recovered digital data line.
An operating mode whereby the radio is muted but still continues to analyze receive data to
determine RX signal type.
Serial Communication Interface INput line
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.
Static-RAM chip used for volatile, program/data memory.
An operating mode whereby the radio is muted but still continues to monitor data.
The act of selecting the desired operating system with the system-select switch (also, the name
given to this switch).
Time-Out Timer; a timer that limits the length of a transmission.
Thin Small-Outline Package
Universal Asynchronous Receiver Transmitter.
Microcontrol unit (see MCU).
Voltage-Controlled Oscillator; an oscillator whereby the frequency of oscillation can be varied by
changing a control voltage.
VOice enCODER; the DSP-based system for digitally processing the analog signals, includes the
capabilities of performing voice compression algorithms or voice encoding.
Voltage Standing Wave Ratio