Tait TMAD1A Users Manual

TM8000 mobiles

TM8100 Mobile Radio

Service Manual

MM8100-02-00-812 Version 1.01

October 2003 © Tait Electronics Limited

Contact Information

Tait Radio Communications http://www.taitworld.com

Corporate Head Office
New Zealand

Tait Electronics Ltd
P.O. Box 1645
Christchurch
New Zealand
E-mail: [e-mail]
Website: http://www.taitworld.com

Technical Support:
E-mail: [e-mail]
Website: http://support.taitworld.com

Tait North America

Regional Head Office: United States of America
Tait North America Inc
E-mail: [e-mail]

Canada
Tait North America Inc
E-mail: [e-mail]

Latin America

Tait Latin America
E-mail: [e-mail]

Tait North Asia

Regional Head Office: Hong Kong
Tait Mobile Radio (Hong Kong) Ltd
E-mail: [e-mail]

Beijing
Tait Mobile Radio (Hong Kong) Ltd
E-mail: [e-mail]

Tait South Asia

Regional Head Office: Singapore
Tait Electronics (Far East) Pte Ltd
E-mail: [e-mail]

Thailand
Tait Mobile Radio Ltd
E-mail: [e-mail]

Tait Oceania

New Zealand
Tait Communications Ltd
E-mail: [e-mail]

Australia
Tait Electronics (Aust) Pty Ltd
E-mail: [e-mail]

Tait Europe

Regional Head Office: United Kingdom
Tait Mobile Radio Ltd
E-mail: [e-mail]

2 TM8100 Mobile Radio Service Manual

Note

For the addresses and telephone numbers of the
above regional offices refer to the TaitWorld
website.

October 2003 © Tait Electronics Limited

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-FREE.

TM8100 Mobile Radio Service Manual 3
October 2003 © Tait Electronics Limited

Exclusion of Liability

TAIT’S ENTIRE LIABILITY AND THE LICENSEE’S
EXCLUSIVE REMEDY SHALL BE THE FOLLOWING

:

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ANY LIABILITY TO THE LICENSEE
PERSON WHATSOEVER
SEQUENTIAL DAMAGE ARISING OUT OF OR IN CON-
NECTION WITH ANY USE OR INABILITY OF USING
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.

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BY TAIT
TAIT

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4 TM8100 Mobile Radio Service Manual

. ANY

October 2003 © Tait Electronics Limited

Contents

Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Notes for Readers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Typographical Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Associated Documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Amendment Record. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

List of Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.1 TM8100 Mobile Radio System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1.2 Radio Body. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

1.3 Control Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

1.4 Repair Levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

1.5 Product Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.1 Architecture of Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.2 Operation of Control-head Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

2.3 Operation in Receive Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

2.4 Operation in Transmit Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

2.5 Operation of Frequency Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

3 Disassembly and Re-assembly of Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

3.1 Detachment of Control Head. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

3.2 Disassembly of Control Head . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

3.3 Disassembly of Radio Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

3.4 Re-assembly of Radio Body. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

3.5 Re-assembly and Attachment of Control Head . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

TM8100 Mobile Radio Service Manual 5
October 2003 © Tait Electronics Limited

Preface

Scope of service manual This manual provides information to service technicians for carrying out

level-1 repairs of TM8100 mobile radios. Level-1 repairs entail the
replacement of faulty parts and circuit boards.

The manual does not cover level-2 repairs (repair of circuit boards, with
the exception of certain special items on the boards) and level-3 repairs
(repair of the special items).

The servicing procedures are moreover limited to the control head and
radio body of TM8100 mobile radios. Servicing of all accessories
associated with the radio is covered in the accessories manual.

Summary of service manual The service manual is divided into three sections. The first section

introduces the radio. The main products making up the radio system are
identified (in particular, the control head and radio body), the repair
levels are discussed, and the product codes of the control head and radio
body are given.

In the second section the functioning of the radio is described. The
description is limited to the control head and radio body. The
architecture of the radio, the operation of the control-head circuitry, the
functioning of the radio in the receive and transmit modes, and the
operation of the frequency synthesizer are described.

The third section provides information regarding the level-1 repair
procedures. The information is mainly limited to the procedures for
disassembling and re-assembling the radio. Only a brief outline is given
of the overall repair procedures themselves.

6 TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

Notes for Readers

Enquiries and comments Any enquiries regarding this manual or the equipment that it describes,

as well as any comments, suggestions and notifications of errors, should
be addressed by e-mail to Technical Support ([e-mail]
or to the Technical Support Manager, Tait Electronics Limited, PO Box
1645, Christchurch, New Zealand. Orders for this manual can be placed
with your Tait Dealer.

)

Updates of manual
and equipment

In the interests of improving the performance, reliability or servicing of
the equipment, Tait Electronics Limited reserves the right to upgrade the
equipment or update this manual or both without prior notice.

Copyright All information contained in this manual is the property of Tait

Electronics Limited. All rights are reserved. This manual may not, in
whole or in part, be copied, photocopied, reproduced, translated, stored,
or reduced to any electronic medium or machine-readable form,
without prior written permission from Tait Electronics Limited. All
trade names referenced are the service mark, trade mark, or registered
trade mark of the respective manufacturers.

Disclaimer There are no warranties extended or granted by this manual. Tait

Electronics Limited accepts no responsibility for damage arising from use
of the information contained in the manual or of the equipment and
software it describes. It is the responsibility of the user to ensure that use
of such information, equipment and software complies with the laws,
rules and regulations of the applicable jurisdictions.

TM8100 Mobile Radio Service Manual 7
October 2003 © Tait Electronics Limited

Typographical Conventions

Conventions and alerts In this manual the names of electrical signals are typed in small capitals

using the standard sans-serif font of the document. For example:

TX INHIBIT

Alert notices that appear in the manual are selected from whichever of
the following are appropriate. These alert notices are in accordance with
the ANSI definitions.

Warning!! This alert notice is used when there is a

potential risk of death or serious injury.

Caution This alert notice is used when there is a risk of

minor to moderate injury to people.

Important This alert notice is used to warn about the risk of

equipment damage or malfunction.

Note This alert notice is used to highlight information that is

required to ensure that procedures are performed correctly.

8 TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

Associated Documents

Basic manuals Together with this service manual, the following manuals are of concern

to service technicians. The pair of digits in the third field of the
document product code indicates the language of the document — 00
indicates an English and 03 a multi-lingual document.

MM8100-00-03-804

TM8100 mobile radio — User’s guide

MMAA00-00-00-812

TM8100 mobile radio — Accessories manual

PCB information packages Information on the circuit boards is supplied in the following separate

documents. The information consists of the BOMs (parts lists), grid
reference indexes, PCB layouts, and circuit diagrams.

MMAB12-H5-00-814

Main board (H5/H6) — PCB information package

MMAB12-B1-00-814

Main board (B1) — PCB information package

MMAC20-00-00-814

Control-head board — PCB information package

3DK manuals The following manuals are mainly of concern to third-party developers.

The manuals are supplied in soft-copy form on a 3DK resource CD.

MMAA30-00-00-807

TM8000 3DK hardware developer’s kit — Application manual

MMAA30-02-00-429

TM8000 3DK application board — Software programmer’s manual

MMAA30-02-00-812

TM8000 3DK application board — Service manual

MM8100-00-00-441

TM8100 Computer-controlled data interface — Protocol definition

TM8100 Mobile Radio Service Manual 9
October 2003 © Tait Electronics Limited

Amendment Record

Version Publication date Amended sections and pages

1.00 September 2003 First release

1.01 October 2003 Alert notice added in Section 3
Figures 3.5 to 3.8 updated

10 TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

List of Acronyms

3DK Third-party Developer’s Kit
AC Alternating Cur rent
ACP Adjacent Channel Power
ADC Analogue-to-digital Converter
AGC Automatic Gain Control
ALC Automatic Level Control
ASC Accredited Service Centre
BOM Bill of Materials
CODEC Coder-decoder
CSO Customer Service Organisation
DAC Digital-to-analogue Converter
DC Direct Current
DIN Deutsche Industrie Norm
DSP Digital Signal Processor
DTMF Dual-tone Multi-frequency
FCL Frequency Control Loop
FPGA Field-programmable Gate Array
IPN Internal Part Number
IC Integrated Circuit
IF Intermediate Frequency
IQ In-phase and Quadrature
ISC International Service Centre
LCD Liquid-crystal Display
LED Light-emitting Diode
LO Local Oscillator
PA Power Amplifier
PCB Printed Circuit Board
PLL Phase-locked Loop
RF Radio Frequency
RSSI Received Signal Strength Indication
SMT Surface-mount Technology
TCXO Temperature-compensated Crystal Oscillator
TEL Tait Electronics Limited
UHF Ultra-high Frequency
VCO Voltage-controlled Oscillator
VCXO Voltage-controlled Crystal Oscillator
VHF Very High Frequency

TM8100 Mobile Radio Service Manual 11
October 2003 © Tait Electronics Limited

12 TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

1 Introduction

Scope of section This section introduces the TM8100 mobile radio system. The main

items making up the system are first introduced. There follows
additional information on the radio body and control head — the two
items that are the prime concern of the service manual. Next is a
discussion of the repair levels that govern the servicing of the radio body
and control head. The section concludes with an explanation of the
product codes for these items.

1.1 TM8100 Mobile Radio System

Main items of system The TM8100 mobile radio system is a high-performance

microprocessor-controlled transceiver with a comprehensive range of
accessories. The system is designed primarily for installation in vehicles
but can also be used in desktop, remote-monitoring and similar
applications. The system consists of the following main items:

■ radio body

■ control head

■ audio accessories

■ mounting for radio

■ desktop power supply (optional)

The service manual covers the servicing of the radio body and control
head only. The accessories manual covers servicing of all the remaining
items.

Specifications for system The specifications for the system are not given in this manual, but will

be found instead on the TaitWorld website in the area reserved for
TM8000 products. This ensures that the latest specification data will
always be available to service technicians.

Radio body The radio body contains the transmitter, receiver and microprocessor

circuitry. The radio body also allows for the fitting of an internal options
board to provide additional functions. There are three standard external
connectors on the radio body: an RF connector, power connector, and
auxiliary connector. If an internal options board is fitted, there might or
might not be an associated external options connector. The auxiliary
and external options connectors allow for the connection of various
external devices.

TM8100 Mobile Radio Service Manual Introduction 13
October 2003 © Tait Electronics Limited

Figure 1.1 Illustrations of the TM8115 mobile radio showing both the front and rear

14 Introduction TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

Figure 1.2 Illustration of the front of the TM8105 mobile radio

Control head

The control head is attached to the radio body. There is a choice of two
control heads:

■ two-digit-display control head

■ blank control head

The two-digit display control head provides the interface with the radio
user and includes a socket for the connection of a microphone. The
blank control head has no user interface but has a single external
connector called the programming connector; this is typically used for
programming and monitoring purposes. The radio is designated
TM8115 with the two-digit-display control head and TM8105 with the
blank control head. Illustrations of these radios are given in Figure 1.1
and Figure 1.2.

Audio accessories One or more audio accessories may be connected to the control head

and radio body. A microphone is the accessory usually required; other
accessories that are available are a handset, high-power remote speaker,
and hands-free kit. Various external devices may also be connected. The
user’s guide and accessories manual describe the audio accessories.

TM8100 Mobile Radio Service Manual Introduction 15
October 2003 © Tait Electronics Limited

RF ANTENNA

RF

CONNECTOR

DEVICE

EXTERNAL

FREE

HANDS-

EXTERNAL OPTIONS

CONNECTOR

AUXILIARY

RADIO BODY

KIT

CONNECTOR

FUSES

POWER

CONNECTOR

VEHICLE

HIGH-

POWER

BATTERY

REMOTE

SPEAKER

RADIO SYSTEM

CONTROL

HEAD

CONNECTOR

MICROPHONE

PHONE

MICRO-

MOUNTING

PLATE

HANGER

dwls

Figure 1.3 Block diagram of an example installation of the TM8115 mobile radio in a vehicle

16 Introduction TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

RF ANTENNA

DEVICE

EXTERNAL

BACK-UP

BATTERY

AC MAINS

RF

CONNECTOR

RADIO SYSTEM

CONTROL

AUXILIARY

RADIO BODY

HEAD

EXTERNAL OPTIONS

CONNECTOR

CONNECTOR

POWER

CONNECTOR

CONNECTOR

MICROPHONE

DESKTOP POWER SUPPLY

OR

MICRO-

DESKTOP

HANDSET

PHONE

Figure 1.4 Block diagram of an example desktop installation of the TM8115 mobile radio

TM8100 Mobile Radio Service Manual Introduction 17
October 2003 © Tait Electronics Limited

dwls

RF ANTENNA

DEVICE

EXTERNAL

DEVICE

EXTERNAL

FUSES

VEHICLE

BATTERY

RF

CONNECTOR

EXTERNAL OPTIONS

RADIO SYSTEM

CONNECTOR

RADIO BODY

BLANK

CONTROL

HEAD

AUXILIARY

CONNECTOR

POWER

CONNECTOR

CONNECTOR

PROGRAMMING

MOUNTING

DEVICE

EXTERNAL

Figure 1.5 Block diagram of an example installation of the TM8105 mobile radio in a vehicle

18 Introduction TM8100 Mobile Radio Service Manual

October 2003 © Tait Electronics Limited

dwls

Installation kits and
desktop power supply

The mounting hardware for the radio is in the form of a U-cradle. It is
supplied in an installation kit and provides for the installation of the radio
in a vehicle. Alternatively, the radio might be needed for desktop use, in
which case a desktop power supply is required. In some desktop
installations the U-cradle is used to attach the radio to the power supply.
The user’s guide and accessories manual describe the installation kit.

Block diagrams of system The block diagrams of Figure 1.3 to Figure 1.5 illustrate possible

configurations of the radio system. Figure 1.3 and Figure 1.4 show
example installations of the TM8115 radio (with two-digit-display
control head) in a vehicle and on a desktop. Figure 1.5 shows an example
of the TM8105 radio (with blank control head) installed in a vehicle.
Different audio accessories are shown connected to the radio. The
hands-free kit is connected to the auxiliary connector, and the remote
speaker to the power connector. The accessories that may be connected
to the microphone connector include the rugged microphone, as well as
a DTMF microphone, desktop microphone, and handset.

1.2 Radio Body

Main, digital and
internal options boards

The radio body consists of a rectangular case — or chassis — with a lid.
The case houses a main board with the receiver and transmitter circuitry,
and a digital board with the microprocessor that controls the radio.
There are different main boards available covering different frequency
bands and with different RF performances; refer to the product codes in
Figure 1.8. The digital board is reflow-soldered to the main board.
There is space in the lid for an optional internal options board. The
essentials of the arrangement are illustrated in the block diagram of
Figure 1.6.

Main-board assembly The rear edge of the main board is attached to a heat-transfer block. The

block is in thermal contact with the rear of the case, where there are
cooling fins for heat dissipation. Heat from the output stage of the
transmitter is conducted via the heat-transfer block to the rear and
radiated from the cooling fins. (The lower surface of the case is ridged
to augment the dissipation of heat.) The RF, auxiliary and power
connectors are fixed to the rear of the main board. They project through
apertures in the heat-transfer block and the rear of the case. The main
board, digital board, and heat-transfer block constitute a separate unit
called the main-board assembly.

Internal options boards Either Tait-designed or custom internal options boards may be fitted in

the radio body. Full details of the boards are given in the accessories
and 3DK manuals. Any internal options board that is fitted might or
might not include an external options connector. If included, the
connector will project through an aperture in the rear of the lid. If there
is no connector, the aperture is sealed with a bung.

TM8100 Mobile Radio Service Manual Introduction 19
October 2003 © Tait Electronics Limited