Tait TB9100 User manual

TB9100 base station
Reciter Service Manual
MBA-00017-01
Issue 1
January 2006

2TB9100 Reciter Service Manual
© Tait Electronics Limited January 2006
Tait Contact Information
Tait Radio Communications
Corporate Head Office
Tait Electronics Ltd
P.O. Box 1645
Christchurch
New Zealand
For the address and telephone number of
regional offices, refer to the TaitWorld
website:
We b s i t e : http://www.taitworld.com
Technical Support
For assistance with specific technical issues,
contact Technical Support:
E-mail: [e-mail]
We b s i t e : http://support.taitworld.com
To our European customers:
Tait Electronics Limited is an environmentally responsible company which
supports waste minimization and material recovery. The European Union’s
Waste Electrical and Electronic Equipment Directive requires that this
product be disposed of separately from the general waste stream when its
service life is over. Please be environmentally responsible and dispose
through the original supplier, your local municipal waste “separate
collection” service, or contact Tait Electronics Limited.

TB9100 Reciter Service Manual 3
© Tait Electronics Limited January 2006
Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Scope of Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Enquiries and Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Updates of Manual and Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Copyright . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Disclaimer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Signal Naming Convention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Bus Numbering Convention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Associated Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Publication Record . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1 Replacing the Network Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.1 Equipment Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
1.2 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
1.3 Before You Start. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.4 Removing the Faulty Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1.5 Replacing the Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
1.6 Restoring the Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2 Reciter Circuit Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3 Digital Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.1 Digital IF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.2 Digital Signal Processor (DSP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.3 Reduced Instruction Set Computer (RISC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.4 40MHz Digital Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4 Reference Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.1 Synthesizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.2 VCXO. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.3 Reference Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
5 Network Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
5.1 Top Level Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
5.2 Risc Processor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
5.3 Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
5.4 DSP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

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5.5 I/O Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.6 Ethernet Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
5.7 Audio and E&M Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
5.8 Clock Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
5.9 Power Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
6 RF Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.1 Receiver RF Circuitry - VHF Reciter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.2 Receiver RF Circuitry - UHF Reciter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
6.3 Exciter RF Circuitry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
7 Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
7.1 RF PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
7.2 Digital PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
8 Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103
8.1 Appendix A – I2C Device Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
8.2 Appendix B – ASIF Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
8.3 Appendix C – Test Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
8.4 Appendix D – Processor Port Assignments. . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
8.5 Appendix E – Component Locations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

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© Tait Electronics Limited January 2006
Preface
Scope of Manual
Welcome to the TB9100 Reciter Service Manual. This manual provides
servicing information for the TB9100 reciter. All other TB9100 base station
servicing information is the same as the information provided in the
TB8100 Service Manual.
Enquiries and Comments
If you have any enquiries regarding this manual, or any comments,
suggestions and notifications of errors, please contact Technical Support
(refer to “Tait Contact Information” on page 2).
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 update the
equipment or 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, trademark or registered trademark 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.

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Terminology
To align with the PowerPC documentation, this document uses the term
“word” to refer to a 32-bit number; a 16-bit number is referred to as a “half-
word”. This convention is continued through the sections in this document
relating to the DSP. However, other documentation on the DSP may refer
to a “word” as being a 16-bit quantity.
In this text, the term “asserted” refers to a signal being driven to its active
state, regardless of whether that active state is logic high or logic low.
Conversely, the term “negated” refers to a signal being driven to its inactive
state.
Signal Naming Convention
Active low logic signals are indicated in the text with an overbar or by a
negation bubble on schematic symbols. However, due to limitations of the
schematic editor, active-low signal names have been indicated on the
schematics with an “_N” suffix.
Hexadecimal numbers are indicated with a “0x” prefix. Binary numbers are
indicated with a “0b” prefix.
Bus Numbering Convention
Signals that are grouped in a bus will be labelled thus:
Bus_name[most_significant_bit .. least_significant_bit]eg. D[31..0]
Note The PowerPC architecture defines the numbering of data and
address buses in the reverse order to normal convention. Hence,
D0 is the msb and D31 is the lsb of the data bus. Other devices in
the ASIF use conventional numbering order; the transition from
PowerPC numbering order to normal numbering order occurs at
the external pins of the PowerPC processor.
Associated Documentation
TB8100 Service Manual.
TB9100 Specifications Manual.
TB9100 Installation and Operation Manual.
TB9100 Customer Service Software User’s Manuals and online Help.
TB9100 Calibration Kit User’s Manual and online Help.
TB9100 Network Installation Guide.

TB9100 Reciter Service Manual 7
© Tait Electronics Limited January 2006
Technical notes are published from time to time to describe applications for
Tait products, to provide technical details not included in manuals, and to
offer solutions for any problems that arise.
All available TB9100 product documentation is provided on the CD
supplied with the base station1. Updates may also be published on the Tait
Technical Support website (http://support.taitworld.com).
Publication Record
Glossary
1PPS One Pulse Per Second
100BaseT 100Mbps ethernet over a twisted pair network
10BaseT 10Mbps ethernet over a twisted pair network
2W Two wire, an audio interface with a single cable
pair shared for both transmit and receive signals
4W Four wire, an audio interface with separate
cable pairs for transmit and receive signals
APCO Association of Public Safety Communications
Officers, a US body of public safety
communications users (eg. Police, Fire) which
defines standards on behalf of its members
ASIF APCO SIF, the system interface from a base
station to an APCO network. Also known as
the network board.
ATM Asynchronous Transfer Mode
BD Buffer Descriptor
BDM Background Debug Mode, a method of
debugging software on a RISC processor
BGA Ball Grid Array, a type of integrated circuit
package
Big Endian A memory ordering scheme where the most-
significant byte of a word occupies a lower
memory address than the least-significant byte
c.f. Little Endian
1. Technical notes are only available in PDF format from the Tait support
website. Consult your nearest Tait Dealer or Customer Service Organiza-
tion for more information.
Issue Publication Date Description
1 January 2006 First release

8TB9100 Reciter Service Manual
© Tait Electronics Limited January 2006
BRG Baud Rate Generator
BS Refers specifically to the Reciter control
element of the base station
CPM Communications Processor Module, a RISC
processor dedicated to handling
communications interfaces
CSMA/CD Carrier Sense Multiple Access with Collision
Detection
CTS Clear to Send
DARAM Dual-Access RAM
DCE Data Communications Equipment
DMA Direct Memory Access, a method of moving
data to/from memory with hardware assistance
DRAM Dynamic Random Access Memory
DSP Digital Signal Processor, a processor specialized
for numerical processing
DSR Data Set Ready
DTE Data Terminal Equipment
DTLB Data Translation Lookaside Buffer
DTR Data Terminal Ready
E&M Ear and Mouth, a simple DC signalling scheme
used in telecom networks
E2PROM Electrically Erasable Programmable Read Only
Memory
EDO Extended Data Out, a type of DRAM
EHPI Enhanced Host Port Interface, now renamed as
HPI
EMC Electromagnetic Compatibility
EMIF External Memory Interface
EPROM Erasable Programmable Read Only Memory
ESD Electrostatic Discharge
FEC Fast Ethernet Controller
FIFO First-In/First-Out, a variable length shift
register that supports queuing of data streams
FLASH A type of electrically erasable programmable
read-only memory. Usually not byte-erasable.
HPI Host Port Interface, an interface between a
DSP and its host processor
GPCM General-purpose Chip-select Machine, a basic
user programmable memory controller
GPR General purpose register

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© Tait Electronics Limited January 2006
Harvard architecture A type of computer architecture that utilizes
separate memory spaces for executable code
and data. cf. von Neumann architecture
HW Hardware
I2C Inter-Integrated Circuit, a serial
communications interface mainly intended for
interconnecting ICs contained within a single
PCB
IPN Internal Part Number, TEL's internal part
numbering system.
ITLB Instruction Translation Lookaside Buffer
IU Integer Unit
JTAG Joint Test Action Group, a test interface
specification for PCB assembly testing
Little Endian A memory ordering scheme where the least-
significant byte of a word occupies a higher
memory address than the most-significant byte
c.f. Big Endian
LRU Least Recently Used, a method of updating
cache memory contents
lsb Least significant bit
LSU Load/Store Unit
LVTTL Low Voltage TTL, logic specified for operation
at 3.3V supply and compatible with 5V TTL
family logic levels ie. VIH = 2.0V and
VIL=0.8V
MAC Media access controller, an ethernet controller
McBSP Multi-channel Buffered Serial Port
MII Media Independent Interface, an interface for
ethernet PHY devices
MIPs Million Instructions Per Second
MMU Memory Management Unit
MOSFET Metal Oxide Semiconductor Field Effect
Transistor
MPC MPC859TPZ133 PowerQUICC
microprocessor
NMI Non-maskable interrupt
OTP One Time Programmable, a non-volatile
memory device that cannot be erased and
reprogrammed after initial programming
msb Most significant bit
PBGA Plastic BGA
PCM Pulse Code Modulation

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PCMCIA Personal Computer Memory Card
International Association
PCM highway A TDM bus typically used for interconnecting
CODECs and DSPs
PHY Ethernet PHYsical interface
PIT Periodic Interrupt Timer
PLL Phase-Locked Loop
PowerPC™ A microprocessor architecture defined by IBM
and Motorola
PowerQUICC™ PowerPC Quad Integrated Communications
Controller, a PowerPC integrated with a
QUICC
pp Peak to Peak
PPC PowerPC™
ppm Parts Per Million
PSTN Public Switched Telephone Network
QUICC™ Quad Integrated Communications Controller,
a version of a CPM
Reciter Receiver/Exciter - the RF signal handling parts
of the base station excluding the power
amplifier
RISC Reduced Instruction Set Computer, a general-
purpose processor
RS-232 A standard defining electrical parameters for
serial interfaces
RSSI Received Signal Strength Indication
RTS Request To Send
Rx Receive
RxD Receive Data
SARAM Single-Access RAM
SCC Serial Communications Controller
SDMA Serial DMA
SDRAM Synchronous Dynamic Random Access
Memory
SIF System Interface
SIO Synchronous Input/Output, a simplified
version of SPI
SIU System Interface Unit
SMC Serial Management Controller
SMI Serial Management Interface, an interface for
management and control of ethernet PHYs

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© Tait Electronics Limited January 2006
Software When ‘software’ is not otherwise qualified, it
refers to the ASIF software that is the subject of
this document
SPI Serial Peripheral Interface, a simple serial
communications interface mainly used for I/O
expansion on microprocessors
SPR Special Purpose Register, a type of register used
for configuration and control of the PowerPC
CPU core
SRAM Static Random Access Memory
SW Software
TAP Test Access Port
TDM Time Division Multiplex
Telco Telephone Company
TSA Time Slot Assigner
TTL Transistor-Transistor Logic, an early bipolar
logic family
Tx Transmit
TxD Transmit Data
UART Universal Asynchronous Receiver/Transmitter
UPM Universal Programmable Machine, a type of
user programmable memory controller
USART Universal Synchronous/Asynchronous
Receiver/Transmitter
UTOPIA Universal Test & Operations PHY Interface for
ATM
VCTCXO Voltage-Controlled Temperature Compensated
crystal Oscillator
Vocoder Voice coder, a program that encodes voice
signals into a digital representation, or vice
versa
von Neumann architecture A type of computer architecture that combines
executable code and data into the same
memory space. cf. Harvard architecture.

12 TB9100 Reciter Service Manual
© Tait Electronics Limited January 2006

TB9100 Reciter Service Manual Replacing the Network Board 13
© Tait Electronics Limited January 2006
1 Replacing the Network Board
This section describes how to troubleshoot and replace a faulty reciter
network board. Servicing procedures for the reciter digital board and the
reciter RF board are covered in the TB8100 Service Manual.
1.1 Equipment Required
■Anti-static work environment
■PC with Ethernet cable.
■Torque screwdriver (4.5in-lbs) with Torx T-10 bit
■TB9100 subrack (PA not required)
Figure 1.1 Network Board
DSP LED
flexible
connector
bridge
board
locating
pins
PowerPC LED Activity LED Tx LED 1PPS coaxial cable

14 Replacing the Network Board TB9100 Reciter Service Manual
© Tait Electronics Limited January 2006
■Power cable, PMU to reciter
■Ethernet switch or hub (if available)
1.2 Troubleshooting
Before replacing the network board, carry out the following tests on the
reciter to exclude other causes and to verify that the fault actually lies in the
network board hardware.
1. Connect the reciter to the subrack via the I2C bus and the DC power
cable. Apply power. This checks whether the digital board is working
and receiving communications from the network board.
a. If no LEDs light on the control panel or rear panel, check that
power is being supplied to the reciter.
b. If the control panel power LED comes on first, followed by the
others, the digital board firmware is working.
c. If the control panel LEDs all remain on for more than 30 seconds,
the digital board is not receiving communications from the net-
work board.
2. Carry out a visual check of the LEDs on the rear of the reciter to
check the network board’s functional subsystems.
a. If all LEDs are off, open the reciter and check the flexible
connector (it supplies power to the network board). Replace if
faulty (see step 5. on page 17).
b. If the PowerPC LED is flashing quickly (2 Hz), the operating sys-
tem kernel is running. If it is flashing slowly (0.5 Hz), only the
bootloader is running. If the Power PC LED does not flash, check
that there is power to the board. The Tx LED should flash once
when power is connected. If it does, power is present, so the boot-
loader must be faulty (see step 7. on page 15).
c. If the orange LED is flashing, the DSP software in the network
board is executing code. If the LED doesn’t flash, open the reciter
and check that the bridge board is connecting properly.
d. The green Ethernet LED should flash if the digital line is con-
nected to an Ethernet switch. This indicates that the digital line is
receiving activity pulse from the Ethernet switch.
3. Connect to the network board’s serial port to test its functioning.
a. Connect your PC to the 9-pin serial connector on the back of the
reciter.
b. Run a program such as HyperTerminal, Teraterm or minicom.
c. Select the following port settings: 57600 baud, 8 bits, no parity, 1
stop bit, no flow control.
d. Press the ‘Enter’ key. If a login prompt appears, the kernel is run-
ning. If the bootloader prompt (=>) appears, contact Tait for

TB9100 Reciter Service Manual Replacing the Network Board 15
© Tait Electronics Limited January 2006
assistance with re-loading the kernel and application software.
e. Note down the reciter’s IP address that is displayed at the login
prompt and close the session.
4. Connect the PC to the network board over its digital Ethernet line.
a. Using the IP address you noted down, ping the reciter from the
Windows command prompt. If there is a response, the network
board’s Ethernet interface circuitry is functioning in both
directions. If there is no response, replace the board.
b. Attempt to connect the CSS to the reciter. If this is successful, the
network board application is running. Check the Alarm Status
screen for reciter alarms. Carry out the control panel LED diag-
nostic test.
5. If there is no obvious hardware fault, replace the current firmware
and/or kernel to see if this fixes the problem.
a. If possible, use the CSS to upload the firmware.
b. Otherwise, follow TN-997 to replace the kernel and/or the
firmware using telnet and a TFTP server.
6. Exclude the base station configuration as the source of problems by
programming in a new configuration.
a. In the CSS, connect to the reciter.
b. Read the configuration and save it to file.
c. Select File > New.
d. Modify the new configuration as necessary.
e. Program the new configuration into the reciter, leaving its current
IP address and netmask.
7. Attempt to access the bootloader prompt. If this is unsuccessful, the
bootloader is faulty. The reciter will need to be returned to Tait
Electronics Limited for the bootloader to be repaired.
8. If the network board fails some or all of the above tests, replace it as
described below.
1.3 Before You Start
Make sure you have a backup of the current base station configuration.
Obtain it from the customer or, if possible, use the CSS to connect to the
reciter, read the configuration, and save it to a file.

16 Replacing the Network Board TB9100 Reciter Service Manual
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1.4 Removing the Faulty Board
1. Remove the M3 Torx screws securing the cover on the digital side of
the reciter. Lift off the cover. (The digital side is nearest to the 9-way
D and RJ45 connectors.)
2. Remove the two M3 Torx screws that secure the rear panel on the
digital side of the reciter.
3. Disconnect the coaxial cable from the network board and lift off the
bridge board.
4. Disconnect the flexible connector by gently levering up the lugs on
the ends of the latch. The flexible connector springs free.
5. Remove the eight M3 Torx screws that secure the network board to
the heatsink.
6. Carefully lift the network board off the locating pins and remove it
from the heatsink.
Important Flexing the board may damage the PCB tracking or break
solder joints.
If the board is a snug fit on the locating pins, you may have to very
gently lever the board with a screwdriver, beginning at the right-hand
side (as viewed in Figure 1.1), to get it to lift.
1.5 Replacing the Board
Important Be very careful to keep the replacement board scrupulously
clean. The board is densely populated and the smallest par-
ticle of conductive dust can cause a short.
Important Make sure the insulator sheet is correctly positioned and flat
on the heatsink. Although this sheet is an electrical insula-
tor, it is also thermally conductive and must allow the PCB
to sit as flat as possible to provide effective heatsinking.
Operating the reciter without the insulator sheet in
place will result in permanent damage to the digital
or system interface PCBs.
1. Make sure that there is no debris on the underside of the network
board.
2. Position the replacement network board over the locating pins and
press it down over them so that it is firmly seated against the insulator
sheet on the heatsink.

TB9100 Reciter Service Manual Replacing the Network Board 17
© Tait Electronics Limited January 2006
3. Replace the eight M3 Torx screws and tighten them to the correct
torque.
Important Do not exceed 4.5in-lbs of torque; greater torque settings
may damage the PCB. Inadequately tight screws can affect
the EMC properties of the board.
4. Position the bridge board above the sockets and the right way round.
Press it into place.
5. Carefully reconnect the flexible connector as shown in Figure 1.2. (If
required, fit a new flexible cable. It must be correctly formed to
prevent excessive stress on the cable or the connector.) Make sure that
the cable is properly located before pressing the latch down.
6. Reconnect the 1 PPS coaxial cable.
7. Replace the rear panel and the reciter cover. Tighten the Torx screws
to the correct torque. Inadequately tight screws can affect the EMC
properties of the board.
8. Return the faulty board to Tait.
Figure 1.2 Reconnecting the Flexible Connector
flexible connector inserted
straight into socket
blue stripe on same
side as latch latch pushed fully down
at both ends

18 Replacing the Network Board TB9100 Reciter Service Manual
© Tait Electronics Limited January 2006
1.6 Restoring the Configuration
1. Connect the CSS to the reciter using the correct IP address (network
boards are given the IP address 192.168.1.2 in the factory.)
2. Restore the base station’s configuration, overwriting the IP address.
3. Reset the reciter. On power-up, the reciter uses the new IP address.
4. Use the procedures in the Troubleshooting section above to verify
correct operation of the network board.

TB9100 Reciter Service Manual Reciter Circuit Descriptions 19
© Tait Electronics Limited January 2006
2 Reciter Circuit Descriptions
This chapter describes the circuitry used in VHF and UHF reciters.
Much of this circuitry is common to both frequency bands, and is therefore
covered by a single description in this chapter. Where the circuitry differs
between VHF and UHF, separate descriptions are provided for each
frequency band. In some cases the descriptions refer to specific VHF or
UHF bands or sub-bands, and these are identified with the letters listed in
the following table.
The reciter comprises three PCBs: an RF, a digital, and a network PCB.
These PCBs are mounted on a central chassis/heatsink. Figure 2.1 on
page 20 shows the configuration of the main circuit blocks, and the main
inputs and outputs for power, RF and control signals. The locations of the
main circuit blocks on the PCBs are shown in Figure 5.1 on page 36.
Table 2.1 TB9100 frequency bands
Frequency
Identification Frequency Band and Sub-band
VHF
B band B1 = 136MHz to 174MHz
B2 = 136MHz to 156MHz
B3 = 148MHz to 174MHz
UHF
H band H0 = 400MHz to 520MHz
H1 = 400MHz to 440MHz
H2 = 440MHz to 480MHz
H3 = 470MHz to 520MHz

20 Reciter Circuit Descriptions TB9100 Reciter Service Manual
© Tait Electronics Limited January 2006
Figure 2.1 Reciter High Level Block Diagram
DSP
CODEC
CODEC
CODEC
40MHz
Clock
Receiver
Exciter
Synthesizer
Subsystem
Reference
Frequency
Subsystem
Digital
Receiver
Power
Supply
Power
Supply
RISC
DSP/RISC
CODECs
IF
12.8MHz
Ref.
RF I/P
28VDC I/P
28V
28V 5V
3.3V
8.5V
RF O/P +
PA Key Audio
System
Control Bus S
y
stem I/O
Digital
Receiver
Audio &
RSSI
Control &
Communications
Control &
Communications
Modulation
& Frequency
Control
Control &
Communications
External
Reference
Frequency
(if used)
RF Board Digital Board
ASIF
Board