Controller Section Theory Of Operation; Introduction; Theory Overview - Motorola MCS 2000 Service Instructions Manual

Controller Section
Theory of Operation

Introduction

Theory
Overview
The radio is a microcontroller-based dual mode (trunked/conventional)
transceiver. The microcontroller determines the active state of the radio
(transmit/receive), monitors radio status, and processes operator commands
entered from the keypad or the other radio controls.
In the Low and Mid Power versions of the radio all radio circuitry is contained
on a single rigid printed circuit board (PCB). In the High Power version of the
radio, the physical arrangement of the circuitry is the same except the power
amplifier (PA) part of the transmitter is contained on a separate PCB.
The radio is composed of the following three major functions:
• RF (Receiver and Transmitter)
• Controller (Main Controller and DC Power Control and Regulation
• Control Head
The RF section is band specific circuitry described in one of the frequency
range specific Volume 2s depending on the band split (See "Related
Publications" on page 1-1).
The Control Head connects to the radio via an 18 pin connector. There are
three different control head types of varying complexity: Model I, Model II
and Model III. Control Head information is covered in this volume of the
manual.
The Controller section is physically separated into two functional sections, i.e.
the Main Controller and the DC Power Control and Regulation.
The controller section of the radio is a microcomputer-based processor that
controls the radio in accordance with its built in programming as well as
commands input manually by the radio operator. The radio operator inputs
manual commands to the controller section using the push-button and other
controls located on the radio control head. In addition to its controlling
functions, the controller section provides audio amplification of the audio
output signal from the receiver section. It also controls and processes a squelch
signal output from the receiver back end section to control the receiver's audio
squelch function.
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Controller Section Theory of Operation

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