Overview
Theory of Operation
4-1
1.0
Overview
This section provides a detailed theory of operation for the radio and its components. The main radio
is a single board design, consisting of the transmitter, receiver, and controller circuits.
The control head is either mounted directly on the front of the radio or connected via an extension
cable in remote mount operation. The control head contains a speaker, LED indicators, a
microphone connector, buttons and dependent of radio type, a display. These provide the user with
interface control over the various features of the radio.
In addition to the power cable and antenna cable, an accessory cable can be attached to a
connector on the rear of the radio. The accessory cable provides the necessary connections for
items such as external speaker, emergency switch, foot operated PTT, ignition sensing, etc.
2.0
Open Controller
2.1
General
The radio controller consists of 4 main subsections:
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■
Digital Control
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■
Audio Processing
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■
Power Control
■
■
Voltage Regulation
The digital control section of the radio board is based upon an open architecture controller
configuration. It consists of a microprocessor, support memory, support logic, signal MUX ICs, the
On/Off circuit, and general purpose Input/Output circuitry.
The controller uses the Motorola 68HC11K1 microprocessor (U0101). In addition to the
microprocessor, the controller has 3 external memory devices. The 3 memory devices consist of a
32 kByte SRAM (U0103), a 256kByte FLASH EEPROM (U0102), and an optional EEPROM (U0104
or U0107) upto 16kByte.
Note:
From this point on the 68HC11K1 microprocessor will be referred to as µP or K1µP.
2.2
Voltage Regulators
Voltage regulation for the controller is provided by 3 separate devices; U0631 (LP2951CM) +5V,
U0601 (LM2941T) +9.3V, and UNSW 5V (a combination of R0621 and VR0621). An additional
regulator is located in the RF section.
Voltage regulation providing 5V for the digital circuitry is done by U0631. Input and output capacitors
(C0631/C0632 and C0633-C0635) are used to reduce high frequency noise and provide proper
operation during battery transients. This regulator provides a reset output (pin 5) that goes to 0 volts
if the regulator output goes out of regulation. This is used to reset the controller to prevent improper
operation. Diode D0631 prevents discharge of C0632 by negative spikes on the 9V3 voltage
4
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Содержание MCX600E
Страница 1: ...Issue December 1999 MCX600E Mobile Radio Service Manual w w w m y r a d i o 1 6 8 n e t ...
Страница 6: ...Cautions and Warnings iv w w w m y r a d i o 1 6 8 n e t ...
Страница 8: ...Cautions and Warnings vi w w w m y r a d i o 1 6 8 n e t ...
Страница 10: ...Contents viii Service Manual w w w m y r a d i o 1 6 8 n e t ...
Страница 12: ...Table of Contents 1 ii Introduction w w w m y r a d i o 1 6 8 n e t ...
Страница 16: ...Specifications 1 4 Introduction w w w m y r a d i o 1 6 8 n e t ...
Страница 18: ...Table of Contents 2 ii Model Chart and Accessories w w w m y r a d i o 1 6 8 n e t ...
Страница 22: ...Table of Contents 3 ii Maintenance w w w m y r a d i o 1 6 8 n e t ...
Страница 62: ...Frequency Synthesis 4 24 Theory of Operation w w w m y r a d i o 1 6 8 n e t ...
Страница 64: ...Table of Contents 5 ii PCB Schematic Diagrams and Parts Lists w w w m y r a d i o 1 6 8 n e t ...
Страница 86: ...Table of Contents A ii PL CTCSS Codes w w w m y r a d i o 1 6 8 n e t ...
Страница 88: ...PL Codes A 2 PL CTCSS Codes w w w m y r a d i o 1 6 8 n e t ...
Страница 90: ...Table of Contents B ii Hand Held Control Head PMMN4005 w w w m y r a d i o 1 6 8 n e t ...
Страница 92: ...Table of Contents B 1 ii Introduction Theory of Operation w w w m y r a d i o 1 6 8 n e t ...
Страница 98: ...Theory of Operation B 1 6 Introduction Theory of Operation w w w m y r a d i o 1 6 8 n e t ...
Страница 100: ...Table of Contents B 2 ii PCB Schematic Diagram and Parts List w w w m y r a d i o 1 6 8 n e t ...
Страница 102: ...Hand Held Control Head PMMN4005 B 2 2 Diagrams and Parts List w w w m y r a d i o 1 6 8 n e t ...