Chapter 2: Gtr 8000 Base Radio Theory Of Operation; Functions Of The Gtr 8000 Base Radio Modules; Function Of The Transceiver Module; Figure 5: Transceiver Module (Front View) - Motorola ASTRO 25 GTR 8000 Manual

Chapter 2
GTR 8000 Base Radio Theory of
Operation
For an understanding of the GTR 8000 Base Radio components, review the modules that provide the
base radio functionality, the modules that provide RF distribution functionality (RFDS), and the
backplane that connects to other modules within the site.
This chapter explains how the GTR 8000 Base Radio works in the context of your system.
2.1

Functions of the GTR 8000 Base Radio Modules

The following lists GTR 8000 Base Radio modules:
• Transceiver (XCVR) module (with or without a transceiver option card)
• Power amplifier module
• Fan module
• Power supply module
2.1.1

Function of the Transceiver Module

The transceiver module provides the control, exciter, receiver, and optional transceiver option card for
the base radio.

Figure 5: Transceiver Module (Front View)

The transceiver generates the station reference, which typically must be locked on to one of many
possible external sources. The external source can be either the site controller TDM clocks or the
external reference operating at 5 MHz or 10 MHz.
The transceiver SPI bus allows communication with its receiver and exciter circuitry, as well as the
power supply module and power amplifier module.
Two or three circuit boards in the transceiver are:
Transceiver Control Board
Performs the control management, digital signal processing, and transmit and receive data
formatting for the base radio.
Transceiver RF Board
Contains DC power conversion/regulation and performs receiver and exciter functions.
MN003286A01-E
GTR 8000 Base Radio Theory of Operation
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