Motorola GM1200E User manual

European Publications Department (RPG) Fleet, Hampshire, England
Issue: July 1998
GM1200E
Mobile Radio
Detailed Service Manual
68P64115B15

ii

Cautions andWarnings
iii
CAUTION
ELECTROSTATIC SENSITIVE DEVICES
PRECAUTIONS SHOULD BE TAKENTO MINIMIZE THE RISK OF DAMAGE BY
ELECTROSTATIC DISCHARGETO ELECTROSTATIC SENSITIVE DEVICES (ESDs).
ANY DEVICES EMPLOYING METAL OXIDE SILICON (MOS) TECHNOLOGY ARE
PARTICULARLY SUSCEPTIBLE.
CIRCUIT DIAGRAMS MARKED WITH THE ABOVE SYMBOL INDICATE ELECTRONIC
CIRCUITS (PECs) FOR WHICH ESD HANDLING PRECAUTIONS ARE NECESSARY.
THE USER SHOULD REFER TO BS5783, 1984: HANDLING OF ELECTROSTATIC
SENSITIVE DEVICES. THIS BRITISH STANDARD SUPERSEDES DEF STAN 59-98,
ISSUE 2.

Cautions andWarnings
iv

Cautions andWarnings
v
WARNING
SAFETYWARNINGS
THE ELECTRICAL POWER USED IN THIS EQUIPMENT IS AT A VOLTAGE HIGH
ENOUGH TO ENDANGER LIFE.
BEFORE CARRYING OUT MAINTENANCE OR REPAIR, PERSONS CONCERNED
MUST ENSURE THAT THIS EQUIPMENT IS ISOLATED FROM THE ELECTRICAL
SUPPLY ANDTESTS ARE MADE TO ENSURETHAT ISOLATION IS COMPLETE.
WHEN THE SUPPLY CANNOT BE ISOLATED, MAINTENANCE AND REPAIR MUST BE
UNDERTAKEN BY PERSONS WHO ARE FULLY AWARE OF THE DANGERS INVOLVED
AND WHO HAVE TAKEN ADEQUATE PRECAUTIONS TO PROTECTTHEMSELVES.
COMPONENTS CONTAINING BERYLLIUM OXIDE ARE USED IN THIS EQUIPMENT.
DUST FROM THIS MATERIAL IS A HEALTH HAZARD IF INHALED OR ALLOWED TO
COME INTO CONTACT WITH THE SKIN.
GREAT CARE MUST BE TAKEN WHEN HANDLING THESE COMPONENTS WHICH
MUST NOT BE BROKEN OR SUBJECTED TO EXCESSIVE HEATING. DEFECTIVE
COMPONENTS MUST BE DISPOSED OF IN ACCORDANCE WITH CURRENT
INSTRUCTIONS.
LEAD ACID BATTERIES MAY BE FITTED ASTHE STANDBY BATTERY.CARE MUST BE
TAKEN WHEN REMOVING OR INSTALLING THESE BATTERIES TO:
1. ENSURE THAT THE TERMINALS ARE NOT SHORTED TOGETHER.
2. PREVENT SPILLAGE OF THE CORROSIVE ELECTROLYTE.

Cautions andWarnings
vi

Detailed Service Manual vii
Detailed Service Manual
Contents
Contents
Chapter
1.0 Introduction
Gives a brief introduction into the manual and the service policy.
2.0 Control Head - Level 3 Information
Provides level 3 service information on the Display/Keypad Control Head (K6)
detailed in the following chapters:
2.1 Introduction/Theory of Operation
2.2 PCB/Schematic Diagrams and Parts Lists
3.0 UHF/VHF Radio - Level 3 Information
Provides level 3 service information on the UHF/VHF radio detailed in the
following chapters:
3.1 Introduction/Theory of Operation
3.2 PCB/Schematic Diagrams and Parts Lists

Contents
viii Detailed Service Manual

Introduction 1-i
Chapter 1
Introduction
Table of Contents
Table of Contents
Paragraph Page
1.0 Introduction ................................................................................................ 1
2.0 Scope of Manual ........................................................................................ 1
3.0 How to UseThis Manual ............................................................................ 1
4.0 Warranty and Service Support ................................................................. 1
4.1 Warranty Period........................................................................................... 1
4.2 After Warranty Period.................................................................................. 2
4.3 Piece Parts .................................................................................................. 2
4.4 Technical Support........................................................................................ 2
4.5 Associated Documentation.......................................................................... 2

Table of Contents
1-ii Introduction

Introduction
Introduction 1-1
1.0 Introduction
This chapter outlines the scope and use of the detailed service manual and provides an overview of
the warranty and service support.
2.0 Scope of Manual
This manual is intended for use by experienced technicians familiar with similar types of equipment.
It contains level 3 service information required for the equipment described and is current as of the
printing date. Changes which occur after the printing date maybe incorporated by a complete
Detailed Service Manual revision or alternatively as additions, for example, to Band Specific
information.
3.0 How to UseThis Manual
The detailed service manual contain an introductory chapter giving information on warranty and
support. Chapter 2 contains level 3 service information for the control head . Chapter 3 details level
3 service information for the radios in band specific sub-chapters each containing theory of
operation and schematics/parts lists.Refer to theTable of Contents for a general overview of the
manual.
4.0 Warranty and Service Support
Motorola offers long term support for its products.This support includes full exchange and/or repair
of the product during the warranty period, and service/ repair or spare parts support out of warranty.
Any "return-for-exchange" or "return-for-repair" by an authorised Motorola Dealer must be
accompanied by a Warranty Claim Form.Warranty Claim Forms are obtained by contacting an
Authorised Motorola Dealer.
4.1 Warranty Period
The terms and conditions of warranty are defined fully in the Motorola Dealer or Distributor or
Reseller contract.These conditions may change from time to time and the following notes are for
guidance purposes only.
In instances where the product is covered under a "return for replacement" or "return for repair"
warranty, a check of the product should be performed prior to shipping the unit back to Motorola.To
ensure the product has been correctly programmed or has not been subjected to damage outside
the terms of the warranty.
Prior to shipping any radios back to the appropriate Motorola warranty depot, please contact
Customer Services.All returns must be accompanied by a Warranty Claim Form, available from
your Customer Services representative. Products should be shipped back in the original packaging,
or correctly packaged to ensure no damage occurs in transit.
1

Warranty and Service Support
1-2 Introduction
4.2 AfterWarranty Period
After Warranty period, Motorola continues to support products in two ways.
Firstly, Motorola's Radio Parts and Service Group (RPSG) offer a repair service to both end users
and dealers at competitive prices.
Secondly, RPSG supplies individual parts and modules that can be purchased by dealers who are
technically capable of performing fault analysis and repair.
4.3 Piece Parts
Some replacement parts, spare parts, and/or product information can be ordered directly.If a
complete Motorola part number is assigned to the part, it is available from Motorola Radio Parts and
Service Group (RPSG). If a generic part is listed or only a part description is listed, the part is not
normally available from Motorola. If a parts list is not included, this generally means that no user-
serviceable parts are available for that kit or assembly.
All orders for parts/information should include the complete Motorola identification number. All part
orders should be directed to your local RPSG office.
Head Office
Motorola G.m.b.H.
European Parts Department
65232 Taunusstein
Germany
4.4 Technical Support
Motorola Product Services is available to assist the dealer/distributors in resolving any malfunctions
which may be encountered. Initial contact should be by telephone whenever possible.When
contacting Motorola Technical Support, be prepared with the product model number and the unit’s
serial number.
4.5 Associated Documentation
Publication Number Description
ENLN4051A GM1200E Product Manual (with Level 1/2 repair information)
ENLN4052A GM1200E Produkthandbuch
ENLN4053A Manuel de Produit GM1200E
68P64117B01 Shared Mobile Radio Systems (SMR) using MPT1327
A System Integrators Cookbook
68P02900X57-A Data Application Notes for 1200 Series Radios

Control Head - Level 3 Information 2-i
Chapter 2
Control Head - Level 3 Information
Table of Contents
Table of Contents
Chapter
2.1 Introduction/Theory of Operation
2.2 PCB/Schematic Diagram and Parts List

Table of Contents
2-ii Control Head - Level 3 Information

Introduction/Theory of Operation 2.1-i
Chapter 2.1
Introduction/Theory of Operation
Table of Contents
Table of Contents
Paragraph Page
1.0 Overview ..................................................................................................... 1
2.0 ExplodedView Diagram ............................................................................ 2
3.0 Theory of Operation .................................................................................. 2
3.1 General........................................................................................................ 2
3.2 Power Supplies............................................................................................ 3
3.3 Voltage Regulator Circuit............................................................................. 3
3.4 Power On / Off............................................................................................. 3
3.5 Microprocessor Circuit................................................................................. 4
3.6 Serial Peripheral Interface (SPI).................................................................. 4
3.7 Keypad Keys................................................................................................ 5
3.8 Status LED and Back Light Circuit............................................................... 5
3.9 Liquid Crystal Display (LCD)........................................................................ 5
3.10 Microphone Connector ................................................................................ 6
3.11 Electrostatic Transient Protection................................................................ 6

Table of Contents
2.1-ii Introduction/Theory of Operation

Overview
Introduction/Theory of Operation 2.1-1
1.0 Overview
128 Channel, Keypad/Display Radio Control Head (Model K6)
The features of the radio control head are as follows:
■
■
On/Off Button
■
■
Rocker type Volume Up/Down Control
■
■
Volume Level Indicators (RSSI)
■
■
Backlit Liquid Crystal Display (LCD) with display icons to show call progress and status
■
■
Up/Down scrolling keys for the display
■
■
Left/Right scrolling keys for the display
■
■
3 x 4 CCITT Keypad
■
■
Microphone Socket
■
■
Clear/Edit Button
■
■
Menu Button
■
■
Status Button
■
■
Personality Button
■
■
Data Button
■
■
Call In Absence Button
■
■
Base Call Button
■
■
External Alarm Button
■
■
3 LED’s (Red,Yellow and Green)
2
.
1
213
45
8
6
79
DS 0
MENU
C
P

ExplodedView Diagram
2.1-2 Introduction/Theory of Operation
2.0 ExplodedView Diagram
3.0 Theory of Operation
3.1 General
The control head contains the microphone connector, several buttons to operate the radio, several
indicator Light Emitting Diodes (LED) to inform the user about the radio status and a Liquid Crystal
Display (LCD) with 19 pre - defined symbols, 11 bars and a 24x120 dot matrix for graphical or alpha
- numerical information e.g.channel number, select code, call address name.To control the LEDs
and the LCD, and to communicate with the host radio, the control head uses the Motorola
68HC11E9 or 68HC11E20 (dependent on the used character set) microprocessor.
Gasket
3286006B01
PCB
8486015B05
not field replaceable
Keypad
7586002B03
LCD module
7286003B02
Gasket, LCD
3286005B01
Housing back
1586001B01
Housing, front
Control head
1586000B01
Frame, LCD
0786004B01
LAPD0008-2
Control Head Kit GCN6110A

Theory of Operation
Introduction/Theory of Operation 2.1-3
3.2 Power Supplies
The power supply to the control head is taken from the host radio FLT A+ voltage via connector
J0901 pin 2.The voltage FLT A+ is at battery level and is used for the LEDs, the back light, to power
up the radio via On / Off button and to supply the voltage regulator circuit.The regulator circuit
provides the stabilized +5 volt which is used for the microprocessor circuit, the display, the display
driver and the keypad buttons.The voltage +5V USW also provided by the regulator circuit is used to
buffer the internal RAM of the microprocessor (U0901).The regulated +5V taken from the host radio
via connector J0901 pin 10 (line +5V SOURCE) is only used to switch on or off the voltage regulator
in the control head.
3.3 Voltage Regulator Circuit
Voltage regulator U0891 provides 5V for the control head.The supply voltage FLT A+ for the voltage
regulator is fed via parallel resistors R0893/4 and dual diode D0891 to pin 8 of U0891.The +5 volt
output is switched on and off by the host radio’s 5 volt source via line +5V SOURCE and control
transistor Q0891.When the host radio is switched off the voltage on line +5V SOURCE is at ground
level and switches off transistor Q0891.Pull up resistor R0892 pulls input SHUTDOWN (pin 3) of the
voltage regulator U0891 to FLT A+ level and switches off the output of U0891 (pin 1).When the host
radio is switched on the voltage on line +5V SOURCE of about +5 volts switches on transistor
Q0891 which in turn pulls input SHUTDOWN (pin 3) to ground and switches on the output of U0891.
Input and output capacitors (C0892 / C0893 and C0895 - C0896) are used to reduce high frequency
noise and provide proper operation during battery transients. Diode D0891 prevents discharge of
C0893 by negative spikes on the FLT A+ voltage.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 microprocessor
(U0901) and the display driver (U0902) to prevent improper operation.
The voltage +5V USW derived from voltage FLT A+ is stabilized using resistor R0896 and diode
VR0891 This voltage is used to buffer the microprocessor’s internal RAM. C0898 allows the battery
voltage to be disconnected for a couple of seconds without losing RAM parameters. Diode D0892
prevents radio circuitry from discharging this capacitor.The +5V at the second anode of D0892
speeds up charging of C0898 when the host radio is turned on by a high level at the ignition input
while the supply voltage is applied to the radio.This prevents the microprocessor from accidently
entering bootstrap mode.
3.4 Power On / Off
The On/Off button when pressed switches the radio’s voltage regulators on by pulling ON OFF
CONTROL to high via D0931 and connects the base of Q0932 to FLT A+.This transistor pulls the
line ANALOG 3 low to inform the µ P that the On/Off button is pressed.If the radio is switched off, the
µ P will switch it on and vice versa.If the On/Off button is pressed and held while the radio is on, the
software detects a low state on line ANALOG 3 and switches the radio off.If the radio is switched on
either manually or automatically its +5V source switches on the control head voltage regulator
U0891 via line +5 SOURCE and transistor Q0891 and the control head microprocessor starts
execution.

Theory of Operation
2.1-4 Introduction/Theory of Operation
3.5 Microprocessor Circuit
The control head uses the Motorola 68HC11E9 or 68HC11E20 (dependent on the used character
set) microprocessor ( µ P) (U0901) to control the LEDs, the LCD and to communicate with the host
radio. RAM and ROM are contained within the microprocessor itself.
The clock generator for the microprocessor can use two different configurations:
1.The oscillator inside the microprocessor (U0901) along with a 4 MHz ceramic resonator (Y0922)
and R0920 generate the clock.
2.The oscillator inside the microprocessor (U0901) along with some external components (C0922-
C0924, L0921, R0922,Y0921) generate the 7.9488 MHz clock. Q0921 is used to alter the clock
frequency slightly under software control if there is a possibility of harmonics of this clock source
interfering with the desired radio receive frequency.
The microprocessor E9/E20 (U0101) contains internal 12 (E9) or 20 (E20) Kbytes ROM, 512 (E9) or
768 (E20) bytes SRAM and 512 bytes EEPROM.
The microprocessor’s RAM is always powered to maintain parameters such as the last operating
mode.This is achieved by maintaining 5V at U0901-25. Under normal conditions, when the radio is
off +5V USW is formed by FLT A+ via D0892. C0898 allows the battery voltage to be disconnected
for a couple of seconds without losing RAM parameters. Diode D0892 prevents radio circuitry from
discharging this capacitor.
There are 8 analogue to digital converter ports (A/D) on U0901.They are labelled within the device
block as PE0-PE7.These lines sense the voltage level ranging from 0 to 5V of the input line and
convert that level to a number ranging from 0 to 255 which can be read by the software to take
appropriate action.
U0901-22 is the high reference voltage for the A/D ports on the µ P.Resistor R0927 and capacitor
C0925 filter the +5V reference. If this voltage is lower than +5V the A/D readings will be incorrect.
Likewise U0901-21 is the low reference for the A/D ports.This line is normally tied to ground. If this
line is not connected to ground, the A/D readings will be incorrect.
The MODB (U0901-25) input of the µ P must be at a logic‘1’ for it to start executing correctly.The
XIRQ (U0901-45) and the IRQ (U0901-46) pins should also be at a logic ‘1’.
The microprocessor can determine the keypad type used, by reading the voltages at pins 63 and 64.
Connections JU0911 and JU0912 are provided by the individual keypads.
Capacitors C0927 and C0928 serve to filter out any AC noise on +5V line at U0901.
3.6 Serial Peripheral Interface (SPI)
The host radio (master) communicates to the control head µ P (slave) through its SPI port (BUS).
This port consists of SPI TRANSMIT DATA (SPI MOSI) (U0901-52), SPI RECEIVE DATA (SPI
MISO) (U0901-51), SPI CLK (SPI CLCK BUF) (U0901-53) and a control head select line (CNTL HD
CE) (U0901-54).This BUS is a synchronous bus, in that the timing clock signal SPI CLCK is sent
while SPI data (SPI TRANSMIT DATA or SPI RECEIVE DATA) is sent.Therefore, whenever there is
activity on either SPI TRANSMIT DATA or SPI RECEIVE DATA there should be a uniform signal on
SPI CLK.The SPI TRANSMIT DATA is used to send serial from the host radio to the control head µ P,
and SPI RECEIVE DATA is used to send data from the control head µ P to the host radio.