Page 1 TB7100 base station Service Manual MBB-00005-01 Issue 1 October 2005...
Page 2: Tait Contact Information
Website: http://www.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.
Page 3: Table Of Contents
Tait Contact Information ........
Page 7: Preface
“Tait Contact Information” on page Updates of Manual and Equipment In the interests of improving the performance, reliability or servicing of the equipment, Tait Electronics Ltd reserves the right to update the equipment or this manual or both without prior notice. TB7100 Service Manual...
Page 8: Copyright
Copyright All information contained in this manual is the property of Tait Electronics Ltd. 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 Ltd.
Page 9: Alert Notices
Automatic Level Control Accredited Service Centre Bill of Materials CCTM Computer-Controlled Test Mode CODEC Coder-Decoder Customer Service Organisation Digital-to-Analog Converter Direct Current Digital Signal Processor Electrostatic Discharge Frequency Control Loop Front-End TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 10 Reduced Instruction Set Computing RSSI Received Signal Strength Indication Surface-Mount Device Surface-Mount Technology SMPS Switch-Mode Power Supply Serial Peripheral Interface TCXO Temperature-Compensated Crystal Oscillator Tait Electronics Limited Voltage-Controlled Oscillator VCXO Voltage-Controlled Crystal Oscillator TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 11: Introduction
Introduction The TB7100 is a software and hardware link-configured base station which is designed for operation in large variety of standard frequency ranges. It makes extensive use of digital and DSP technology. Many operating parameters such as channel spacing, audio bandwidth and signalling are controlled by software.
Page 12: Rf Output Power
Product Codes This section describes the product codes used to identify products of the TB7100 base station product line. The product codes of the TB7100 base station product line has the format: TBBaabb-cdd-ee where: aa identifies the frequency band of the transmitter:...
Page 13: Mechanical Design
The modules and components are interconnected by looms and cables. TB7100 Service Manual Mechanical Design © Tait Electronics Limited October 2005...
Page 14: Tray
UI cables (not shown). The UI board also has a speaker connector A volume knob is fitted to the shaft of the volume-control potentiometer. Figure 2.2 UI board Cables not shown. Mechanical Design TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 15: Receiver Module
DC power connector and the 50W/40W version has a black DC power connector. For more information on the connectors, refer to “Connections” on page Figure 2.3 Receiver module TB7100 Service Manual Mechanical Design © Tait Electronics Limited October 2005...
Page 16: Transmitter Module
Torx T10 screws An L-shaped gap pad and (with the 50W/40W version) a rectangular gap are fitted between the board and the heatsink to improve heat transfer. Figure 2.4 Transmitter module Mechanical Design TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 17: Si Board
(to fan power board on fan duct) temperature control connector (to temperature sensor on transmitter heatsink). For more information on the connectors, refer to “Connections” on page Figure 2.5 SI board TB7100 Service Manual Mechanical Design © Tait Electronics Limited October 2005...
Page 19: Functional Description
Tx/ANT (RF Port) Rx/SI Front Panel/ Fan Control UI Board Serial Data connector Transmitter UI/Tx TX/SI SI Board System Interface connector Module DC Power connector Fused Temp. Sensor Internal Power TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 20: Receiver Operation
Software plays a prominent role in the functioning of the radio. When describing the operation of the radio the software must be included with the above. This is considered further below. These functional parts are described in detail below. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 21: Rf Hardware
2 x (IF1 + 64kHz). The quadrature output from this mixer is fed to a pair of ADCs (analog-to-digital converters) with high dynamic range where it is oversampled at 256kHz and fed to the custom logic device. TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 22: Digital Baseband Processing
The following items within the receiver path are calibrated in the Factory: Calibration front-end tuning noise squelch RSSI (received signal strength indication) Information on the calibration of these items is given in the on-line help facility of the calibration application. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 23: Audio Processing And Signalling
UI board via a buffer amplifier. The output configuration of the audio power amplifier is balanced and drives an internal speaker. The power delivered to the speaker is limited by its impedance. The speaker has 16Ω impedance. TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 24: Transmitter Operation
The amplified microphone signal is converted to a digital stream by a 16-bit ADC with integral anti-alias filtering (0.1 to 3.2kHz). The digital stream is transported to the DSP for further audio processing. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 25: Frequency Synthesizer
The FCL provides the reference frequency for the RF PLL. It generates a high-stability reference frequency that can be both modulated and offset in fine resolution steps. TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 26 VCO in the RF PLL, combining to produce a flat modulation response down to DC. Reference modulation is usually applied directly to the TCXO. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 27 FCL nominal frequency; the TCXO frequency itself is not adjusted. The items KVCO and KVCXO are the control sensitivities of the RF VCO (in MHz/V) and VCXO (in kHz/V) respectively. The latter has temperature compensation. TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 28: Rf Power Amplifier
(adjacent channel power). A typical ramping waveform is shown in Figure 3.4. Figure 3.4 Typical ramping waveforms Power Bias Power Power Bias ramp ramp ramp ramp High power power Time Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 29: User Interface Operation
The user interface provides a panel consisting of: two digit, seven-segment LCD display four programmable function keys LED indicators volume control internal speaker connector switch TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 30 The physical connection is via two 18-way ribbon cables. The internal speaker is connected to the UI board via a lead with a mating connector so that it can be easily disconnected. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 31 The calibration application can assist in the tuning of: AD6521 CODEC voltage reference TCXO frequency receiver front end transmitter driver and final gate bias limit transmitter power control deviation and squelch. TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 32: System Interface Operation
(RSSI) receiver gate output receiver inhibit input 13.8V DC (1.5A) output tone on idle (TOI). These functional parts are described in detail below. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 33 RX DIG IO 13v8 out 13V8 OUT RX GATE RSSI PWM 1 PWM 2 13v8 PWM 1 PWM 2 TX DATA RX DATA Temperature TEMP SENSOR sensor Data Fan Control 7.0556 TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 34: Internal Power Distribution
3.3V, 4.5V, 9V, 13.8V 3.4.2 Serial Data Tait High Speed Data (THSD) is a Tait Electronics Ltd. proprietary protocol THSD that can be used with the base station. This allows the base station configured in either data repeater or data modem modes to pass data speeds up to 12kbps on a narrow-band channel and 19.2kbps on a wide-band channel.
Page 35: Transmitter Audio Processing
The receiver gate signal is used by the SI board to control TOI and a relay output. The receiver gate output on the S connector can be used for YSTEM external equipment such as TaitNet trunking controllers. TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 36: Receiver Inhibit
The copper plate is mounted directly to the main heatsink boss and a coating of thermal paste ensures good thermal transfer between these two surfaces. Functional Description TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 37 Figure 3.8 Power distribution TB7100 Service Manual Functional Description © Tait Electronics Limited October 2005...
Page 39: Circuit Descriptions
For up-to-date schematics refer to the relevant PCB information. Sample Schematics TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 40 Figure 4.1 Transmitter and receiver boards hardware architecture Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 41: Transmitter Circuitry
10, 15, 25, and 50 watts (VHF), and 10, 15, 20, and 40 watts (UHF) for 50W/40W boards 1, 5, 12 and 25 watts (all bands) for 25W boards TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 42 Figure 4.2 Block diagram of the transmitter circuitry Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 43 For added protection, a temperature sensor ensures that the transmitter Temperature Sensor power is reduced to very low levels should a temperature threshold be exceeded. If the temperature does not decrease, the transmitter is switched off. TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 44: Receiver Circuitry
Raw demodulated audio can be tapped out from the DSP for use with an external modem. The modem may be connected to the auxiliary connector or to the external options connector when an internal options board is fitted. Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 45 Figure 4.3 Block diagram of the receiver circuitry TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 46 RF signal to pass through the front- end hardware, so that the LO is disabled before the impulse reaches the IF stage where it could cause crystal filter ring. Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 47: Frequency Synthesizer Circuitry
25kHz reference frequency to give any desired frequency that is an integer multiple of 25kHz. There are some constraints imposed by the capabilities of the synthesizer hardware, especially the tuning range of the VCOs. TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 48 Figure 4.4 Block diagram of the frequency synthesizer circuitry Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 49 The resistors and capacitors of the filter affect both the switching time and the stability of the synthesizer; the values of these components have been carefully selected to give optimum control characteristics. TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 50 1MHz or 10MHz in less than 4.5ms. The ramp-up and ramp-down of the transmitter, which totals 1ms, extends this change-over time to 5.5ms.) Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 51: Frequency Control Loop
VCXO is frequency modulated directly by the relevant modulation information. The latter may be the microphone audio, an audio tap-in signal, internal modem signals, or any combination of these. TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 52: Codec And Audio Circuitry
The audio circuitry performs four functions: Audio Circuitry output of audio signal for speaker input of microphone audio signal input of auxiliary audio signal output of auxiliary audio signal Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 53 Figure 4.5 Block diagram of the CODEC and audio circuitry TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 54 ITF AUD TAP IN Input input of IC205. R241 combined with internal clamping diodes in IC205 provide DC protection for the ADC input. IC205 provides the input biasing of approximately 1.5V. Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 55 The DC bias for this signal path is provided by IC204 and is approximately 1.2V when operational. The offset at CDC AUD TAP OUT approximately 2.4V owing to the gain of the buffer amplifier. TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 56: Power Supply Circuitry
These all take advantage of the efficiency gain of the SMPS. The 9V regulator and the 13.8V switched supply are connected to +13 . The two remaining switched supplies (9V and 3V) use P-channel BATT MOSFETs. Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 57 CH ON OFF clock ITF IOP GPIO7 digital AUX GPI3 AUX GPI2 asynchronous serial data +3V3 synchronous serial data Interface +13V8 SW 13V8 Switch Reverse +13V8 BATT Polarity Protection TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 58: Interface Circuitry
1 by removing the link LK2 in the power supply purpose input like AUX GPI area and fitting the 33kΩ resistor R775. Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 59 Regulator Connector AUD TAP OUT AUD TAP IN AUX MIC AUD Frequency AGND RSSI Synthesizer Signal Types: digital Receiver analog asynchronous serial data AGND synchronous serial data clock Transmitter TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 60: Digital Board
Digital Board For a block diagram of the digital board, refer to Figure 4.8. Introduction The digital board is not serviceable at level-2 and is not described in this manual. Circuit Descriptions TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 61 DSP JTAG EMU0 FPGA JTAG TDO DSP JTAG TDO DSP JTAG EMU1 JTAG FPGA TDI JTAG DSP TDI analog clock +3V3 digital AGND Factory Connector asynchronous serial data synchronous serial data TB7100 Service Manual Circuit Descriptions © Tait Electronics Limited October 2005...
Page 63: Connections
System interface Auxiliary System interface J101 SK101 connector connector Transmitter For information on the factory connector and the internal options connector of the transmitter and receiver, refer to the PCB information. TB7100 Service Manual Connections © Tait Electronics Limited October 2005...
Page 64: External Connectors
The DC input leads should be of a suitable gauge to ensure less than 0.2V drop at maximum load over the required length of lead. Connections TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 65 The RF connector is an N-type connector with an impedance of 50Ω. Important The maximum RF input level is +27dBm. Higher levels may damage the radio. Signal Name Signal Type Notes RF analog RF ground rear view TB7100 Service Manual Connections © Tait Electronics Limited October 2005...
Page 66 <0.6 V (10mA sink) input: high ≥1.7 V, low ≤0.7 V Digital output/Tx relay output Rx audio output output 13.8 volt output power output resetable SMD fuse 1.5A Connections TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 68: Internal Connectors
DC power connectors for the 50W/40W and 25W versions. Signal name Signal type Notes AGND ground 50W/40W SPK– analog output not connected SPK+ analog output not connected external view 13.8VDC DC power input external view Connections TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 69 +3V3DC for UI board external view pin 1 closest to PCB CH SPI D1 input input CH SPI CLK output output SPK- no connection output speaker audio SPK+ no connection output speaker audio TB7100 Service Manual Connections © Tait Electronics Limited October 2005...
Page 70: Si Board Connectors
TX_AUX_GPI1 input digital input TX_AUX_GPI2 input digital input TX_AUD_TAP_OUT no connection TX_RSSI no connection TX_MIC_AUD output external view TX_AUD_TAP_IN output Tx audio TX_GND ground ground TX_13V8 no connection no connection Connections TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 71 RX_AUX_GPI2 input digital input RX_AUD_TAP_OUT input receive audio RX_RSSI input RSSI RX_MIC_AUD no connection external view RX_AUD_TAP_IN no connection RX_GND ground ground RX_13V8 no connection no connection TB7100 Service Manual Connections © Tait Electronics Limited October 2005...
Page 72: Ui Board Connectors
RX_CH_SPI_D0 input RX_CH_LE input RX_CH_GPIO1 input digital ground RX_+3V3 input +3V3DC for PCB external view RX_CH_SPI_DI output RX_CH_SPI_CLK input RX_CH_SPK- input speaker audio RX_CH_SPK+ input speaker audio Connections TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 73: General Information
CODEC 1 (IC204) copper plate. Level-2 repairs also comprise the replacement of the connectors on the transmitter and receiver modules, and the external connectors of the UI and SI boards. TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 74 ASC and Tait-only access Log-in passwords are needed for associate and Tait-only access; Technical Support supplies service centres with the necessary log-in information. (The unsecured portion of the Technical Support website is accessible to the general public.
Page 75 PCB information is compiled whenever there is a major change in the layout of the board. PCB information is published on the Technical Support website. An additional source of information to service centres is the Tait FOCUS Tait FOCUS Database call-logging database.
Page 76: Tools, Equipment And Spares
Test Equipment test PC calibration and test unit (TBA0STU or TBA0STP) TB7100 CTU adapter (TBB0STU-TBB, included in TBA0STU) TMAA20-04 cable (RJ12 socket to RJ45 plug, included in TBB0P00) T2000-A19 cable (included in TBB0P00) RF communications test set (audio bandwidth of at least 10kHz)
Page 77: Servicing Precautions
Install the TB7100 programming and calibration applications on the test PC. Product CD These applications are included on the CD (406-00047-xx) supplied with the base station. Servicing Precautions This section discusses the precautions that need to be taken when servicing Introduction the base station.
Page 78 These benches have a dissipative rubber bench top, a conductive wrist strap, and a connection to the building earth. The material of the bench top must satisfy not only anti-static requirements but also the non-scratch requirements mentioned above. General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 79 The frequency ranges 156.8MHz±375kHz, 243MHz±5kHz, and 406.0 to 406.1MHz are reserved worldwide for use by distress beacons. Do not program transmitters to operate in any of these frequency bands. TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 80: Test Equipment Setup
CTU to the YSTEM NTERFACE connector of the base station using the TB7100 CTU adapter YSTEM and the 25-way D-range ribbon cable. Audio connections between the CTU and test equipment are described in the relevant test steps.
Page 81 25-way D-range ribbon cable SI board Transmitter Receiver power connector PROG/MIC TMAA20-04 cable serial port Test PC (RJ12) serial port (DB9) T2000-A19 cable T950-001 USB1.1 to serial DB9 adapter (optional) TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 82 16Ω load is switched into the circuit in place of the test unit’s speaker. Note, however, that the audio out switch has no effect on the speaker. General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 83 To overcome this, connect pins 1 and 13 of a 15-way D-range plug and connect the plug to the auxiliary connector of the banana plugs transmitter module. TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 84: Replacing Board Components
CSO or, in the case of a CSO, from TEL. Always ensure that the replacement component has the identical specification to that given in the BOM. It is particularly important for the tolerances to be the same. General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 85: Shielding Cans And Connectors
LPF TOP DIRC TOP FE TOP PAF TOP VCO TOP (UHF only) IF TOP SYN TOP PAD TOP FCL TOP CDC TOP PL101 Factory Connector SK102 Internal-Options Connector Digital Board TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 86 However, technicians require training in the best techniques to employ in the absence of a can-removal tool. Such training is part of the accreditation process for service centres. General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 87: Smt Repair Techniques
The inductors are part of the SMPS of the SYN TOP power-supply circuitry on the bottom-side of the board. Figure 6.6 on page 90 shows the locations of the components. TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 88 (VHF board. UHF board similar) Note that other components may be fitted for C548 (such as C5085 and C5086 for UHF board) bottom side (UHF board. VHF board similar) General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 89: Computer-Controlled Test Mode (Cctm)
If the character% is accepted, the character – is displayed in response, and the message CL appears on the base station display. This implies that the module has entered CCTM. If the attempt fails, repeat Step 1 Step TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 90 AUD TAP OUT (C=bypass out, D=split, E=splice) (the default is D when y is omitted) General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 91 205 – Erase persistent data None Effectively resets the calibration parameters to their default values TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 92 (any integer from 0 to 3000) 378 – Receiver output level Reads the signal power at the where x is the signal power output of the channel filter (the square of the amplitude) General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 93 (a value from 0 to 1100 mV) 326 – Transmitter power 326 x None Sets the power level of the where x specifies the level transmitter (0=off, 1=very low, 2=low, 3=medium, 4=high, 5=maximum) TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 94 (an integer from 0 to 255) 332 x (to set value) None where x is the DAC value of the required bias voltage (any integer from 0 to 255) General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 95 The supply voltage is less than the V1 threshold. The supply voltage is less than the V2 threshold and the module has powered itself down. The module will not respond to the reset command character ^. TB7100 Service Manual General Information © Tait Electronics Limited October 2005...
Page 96: Visual Indicators
Power is supplied to the base station (through the receiver module) LED is off No power is supplied to the base station Note The base station does not generate audible signals. General Information TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 97: Disassembly And Reassembly
The transmitter module can be identified by the heat transfer plate fitted to the underside, whereas the receiver does not have a heat transfer plate. TB7100 Service Manual Disassembly and Reassembly © Tait Electronics Limited October 2005...
Page 98: Removing The Base Station And Opening The Tray
Use a PZ2 Pozidriv screwdriver to remove the four M6 screws, and remove the base station from the rack. Use a Torx T10 screwdriver to remove the 15 countersunk screws. Remove the tray cover Disassembly and Reassembly TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 99: Replacing The Ui Board
Use a Torx T10 screwdriver to fasten the three screws to 4.5lb·in (0.5N·m). Plug the speaker connector into the UI board. Fit the volume knob onto the shaft and press firmly until fully seated. TB7100 Service Manual Disassembly and Reassembly © Tait Electronics Limited October 2005...
Page 100: Replacing The Receiver Module
Position the receiver module inside the tray chassis. Use a Torx T10 torque-driver to tighten the screws 4.5lbf·in (0.5N·m). Connect the cables to the RF , DC power , system interface and user interface connectors. Disassembly and Reassembly TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 101: Replacing The Transmitter Module
Use a Torx T10 torque-driver to fasten the temperature sensor with the screw to 4.5lbf·in (0.5N·m). Connect the cables to the RF , DC power , system interface and the user interface connectors. TB7100 Service Manual Disassembly and Reassembly © Tait Electronics Limited October 2005...
Page 102: Disassembling The Transmitter Module
With the 25W board, use a Torx T10 screwdriver to undo the two screws Figure 7.5 Removing and fitting the transmitter board Torx T10 4.5lb·in Torx T10 15lb·in 25W: Torx T10, 3lb·in 50W/40W: Torx T6, 1lb·in Disassembly and Reassembly TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 103: Reassembling The Transmitter Module
Figure 7.6 Contact surfaces on the bottom side of the board contact surface of L-shaped gap pad contact surface tin-plated of rectangular copper Audio-PA area gap pad plate TB7100 Service Manual Disassembly and Reassembly © Tait Electronics Limited October 2005...
Page 104 PCB hole Use a Torx T10 torque-driver to fasten the three screws to 15lbf·in (1.7N·m). Use a Torx T10 torque-driver to fasten the four screws to 4.5lbf·in (0.5N·m). Disassembly and Reassembly TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 105: Replacing The Si Board
(PZ1) on the heatsink of U406 to 4.5lb·in (0.5N·m). Connect the system interface cables to the transmitter and the receiver, the fan control cable , the temperature sensor cable , and the DC power cables TB7100 Service Manual Disassembly and Reassembly © Tait Electronics Limited October 2005...
Page 106: Replacing The Fans
Slide the fan duct into the chassis. Plug the fan control loom into the fan power board Use a Torx T10 screwdriver to fasten the four screws to 4.5lb·in (0.5N·m). Disassembly and Reassembly TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 107: Replacing The Fan Power Board
Replacing the Speaker Use a Torx T10 screw driver to remove the two screws securing the Removal speaker to the tray chassis. Fitting is carried out in reverse order. TB7100 Service Manual Disassembly and Reassembly © Tait Electronics Limited October 2005...
Page 108: Final Reassembly
Fit the fuse at the rear of the base station. Note Installation of the base station is described in the installation and operation manual. Figure 7.9 Final reassembly Disassembly and Reassembly TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 109: Servicing Procedures
The fault reported by the Customer Administration might concern damage to or loss of a mechanical part, or the failure of a function, or both. TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 110 LED on lights up. OWER The LCD indicates the current channel number. If the receiver module powers up successfully, go to Step 4. If it does not, go to Step Servicing Procedures TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 111 Instead of the spare UI board, a TMAC20-0T control head can be connected to the transmitter module only. If the transmitter module is faulty, go to “Power Supply Fault Finding” on page 127. Then return to Step TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 112 First cycling the power is essential if the module is programmed to power up in transparent-data mode (both 1200 baud FFSK and Tait high-speed data) and if the selected data port is the microphone connector. Using the microphone as the transparent- mode data port is not a valid base station configuration.
Page 113 If the error persists, read the last system error using CCTM E2 (error 2) command 204. OL (out of lock) Go to “Frequency Synthesizer Fault Finding” on page 143. TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 114 CTU or the PTT key on the fist microphone. The T LED should light up. If the T LED does not light up, replace the UI board. Servicing Procedures TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 115 UI board and cable or the transmitter module is faulty by connecting a spare UI board and cables to both transmitter and receiver. TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 116 “Transmitter Fault Finding (50W/40W)” on page 273 “Transmitter Fault Finding (25W)” on page 219. with the power level set to high (326 4). Repeat Step 7 Step 9 Servicing Procedures TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 117 If this rectifies the fault, the original receiver module is faulty. Reconnect the original receiver module and go to Task Then go to Step TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 118 The receiver is working but there is a fault in the interface circuitry of the Receive Audio but No Rx Gate Signal receiver module. Repair the receiver module as described in “Interface Fault Finding” on page 137. Servicing Procedures TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 119 If there is a fault, test the resistance between pins 1 and 3 of the volume potentiometer is about 10kΩ and the resistance between pin 1 and pin 2 varies linearly between about 0 and 10kΩ. TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 120 Reset RV200 to the correct turn-on temperature. If the fans do not turn on, replace the temperature sensor and repeat from Step Servicing Procedures TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 121: Final Tasks
Test the base station as described in “Final Test” on page 124. It may be necessary to also carry out the audio level adjustments as described in the installation and operation manual. TB7100 Service Manual Servicing Procedures © Tait Electronics Limited October 2005...
Page 122 Level-1 service centres should return the faulty base station to the nearest ASC, and level-2 service centres should return the base station to the ISC. Supply details of the Customer, the fault and, if applicable, the attempted repair. Servicing Procedures TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 123: Power Supply
Figure 8.1 Test sheet TB7000 base stations TB7100 Base Station - Single Channel Test Sheet Test Set-up Details Product Code: TBB__________-_________-________ Test Equipment HP8920 Test Equipment S/N ID _ _ _ _ ________________ Serial Number: Programming App version Rx Configuration file...
Page 125: Power Supply Fault Finding
In this case carry out Task 4 Task 5. With the third fault, the external power required at a particular connector is no longer present. In this case carry out Task TB7100 Service Manual Power Supply Fault Finding © Tait Electronics Limited October 2005...
Page 126 If it does, go to Task 2. If it does not, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. Power Supply Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 127 Figure 9.1 Important components of the power-supply circuitry (bottom side), including 3.3V regulator IC602 C603 pin 7 pin 5 C603 C618 R199 D601 D604 Q709 TB7100 Service Manual Power Supply Fault Finding © Tait Electronics Limited October 2005...
Page 128 If the voltage is correct, the digital board is faulty; replace the main- board assembly and go to “Final Tasks” on page 123. If the voltage is not correct, go to Step Power Supply Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 129 “Initial Tasks” on page 111. If the radio fails to power up, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Power Supply Fault Finding © Tait Electronics Limited October 2005...
Page 130 “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. Power Supply Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 131 2 line goes low Pin 5 of AUX GPI power sense auxiliary connector Internal-options Link out 7 line goes high Pin 15 of IOP GPIO power sense internal-options connector TB7100 Service Manual Power Supply Fault Finding © Tait Electronics Limited October 2005...
Page 132 D601 (see Figure 9.1), via Q600 (see Figure 9.2), to pin 5 of the auxiliary connector SK101. Repair any fault and go to Step Power Supply Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 133 “Final Tasks” on page 123. If the fault could not be found or repairs failed, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Power Supply Fault Finding © Tait Electronics Limited October 2005...
Page 134 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Power Supply Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 135: Interface Fault Finding
Figure 10.3 Figure 10.4 for the locations of the components. These figures show the three areas of the main board where the components of the interface circuitry are situated. TB7100 Service Manual Interface Fault Finding © Tait Electronics Limited October 2005...
Page 136 Components of the interface circuitry (top side near the cans) CDC TOP IF TOP IF TOP CAN CDC TOP CAN Figure 10.3 Components of the interface circuitry (top side at the corner) Interface Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 137 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Interface Fault Finding © Tait Electronics Limited October 2005...
Page 138 Figure 10.4 Components of the interface circuitry (bottom side) Interface Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 139 Configure the suspect line as an output, and then carry out the procedure given in Task Configure the suspect line as an input, and then carry out the procedure given in Task TB7100 Service Manual Interface Fault Finding © Tait Electronics Limited October 2005...
Page 141: Frequency Synthesizer Fault Finding
Set transmit-receive switch on (x=1) or off (x=0) via DIG SYN TR SW line 389 x Set synthesizer mode to slow (x=0) or fast (x=1) 393 1 x Write data x to FPGA TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 142: Initial Checks
UHF (H5 and H6 bands) or VHF (B1 band) radio. The product-code label on the radio body will identify the frequency band as described in “Introduction” on page Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 143 Enter the CCTM command 72 to determine the lock status in receive mode. Note the response. lock status=xyz (x=RF PLL; y=FCL; z=LO2) (0=not in lock; 1=in lock) TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 144 If the lock status is 111, this implies normal operation. But if the lock error persists, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 145: Power Supplies
SUPPLY L506 SIGNAL TYPES ANALOG PINS 7 AND 15 PINS 7 AND 15 OF IC503 OF IC503 CLOCK DIGITAL LOOP AGND FILTER INTERFACE INVERTER CIRCUITRY CIRCUITRY SUMMER TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 146 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 147 6 V regulator IC606 (top side) SYN TOP Pin 5 (5-pin device) (pin not used) B1 band Q512 Q508 Q5004 Measurement point on L506 H5/H6 bands Q512 Q508 Q506 Q507 TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 148 Figure 11.3 Synthesizer circuitry under the can (top side) FCL TOP SYN TOP CAN Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 149 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 150 Figure 11.4 Synthesizer circuitry under the cans (bottom side) SYN BOT VCO BOT B1 band H5/H6 bands Q511 Q505 Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 151 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 152 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 153: Phase-Locked Loop
“Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 154 Figure 11.5 Test and measurement points for the synthesizer PLL and loop filter Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 155 Determine if the fault has been removed. If it has, go to “Final Tasks” on page 123. If it has not, the FCL is suspect; go to “Power Supply for FCL” on page 189. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 156 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 157 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 158 Figure 11.7 Synthesizer circuitry under the can (top side) SYN TOP B1 band Q512 Junction of C541 and R547 H5/H6 bands Q512 Junction of C541 and R547 Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 159: Loop Filter
C565: < 0.5 V DC If the loop voltage is correct, go to Task 12. If it is not, the loop-filter circuitry is suspect; go to Task TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 160 “Final Tasks” on page 123. If it is not, or if no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 161 “Final Tasks” on page 123. If it is not, or if no fault could be found, replace the main- board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 162 “Final Tasks” on page 123. If they are not, or if no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 163 “Final Tasks” on page 123. If they are not, or if no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 164: Receive Vco And Related Circuitry (Uhf Radios)
Minimum and maximum receive frequencies for the different UHF frequency bands Frequency band Receive frequency in MHz Minimum Maximum 337 ± 5 441 ± 5 378 ± 5 498 ± 5 Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 165 Figure 11.8 Measurement points for the VCO and related circuitry in UHF radios TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 166 If the receive frequency measured in Step 4 is correct, go to Task If it is incorrect, go to Task 19. If no frequency is detected, go to Task Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 167 Figure 11.9 Synthesizer circuitry under the cans (UHF radio, top side) SYN TOP VCO TOP Q507 Q506 Tx port Q508 Junction of C541 and R547 Rx port TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 168 123. If it has not, replace the main-board assembly and go to “Final Tasks” on page 123. Figure 11.10 Synthesizer circuitry under the VCO BOT (UHF radio, bottom side) Q5001 Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 169 123. If they are still not correct, go to Step Resolder R542 in position (see Figure 11.9). Replace the main- board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 170 If the voltages measured in Step 3 Step 5 are correct, go to Task 22. If they are not, the switching network is suspect; go to Task Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 171 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 172 “Final Tasks” on page 123. If they are not, or if no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 173: Transmit Vco And Related Circuitry (Uhf Radios)
Minimum and maximum transmit frequencies for the different UHF frequency bands Frequency band Transmit frequency in MHz Minimum Maximum 371 ± 5 492 ± 5 419 ± 5 545 ± 5 TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 174 If the transmit frequency measured in Step 4 is correct, go to Task If it is incorrect, go to Task 25. If no frequency is detected, go to Task Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 175 123. If they are still not correct, go to Step Resolder R542 in position (see Figure 11.9). Replace the main- board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 176 If the voltages measured in Step 2 Step 4 are correct, go to Task 27. If they are not, the switching network is suspect; go to Task Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 177 “Final Tasks” on page 123. If they are not, or if no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 178: Vco And Related Circuitry (Vhf Radios)
Figure 11.11. Table 11.4 Minimum and maximum frequencies for the different VHF frequency bands Frequency band Frequency in MHz Minimum Maximum 84 ± 5 200 ± 5 Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 179 Figure 11.11 Measurement points for the VCO and related circuitry in VHF radios TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 180 If the minimum frequency measured in Step 5 is correct, go to Task 29. If it is incorrect, go to Task 30. If no frequency is detected, go to Task Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 181 Figure 11.12 Synthesizer circuitry under the can (VHF radio, top side) SYN TOP Tx port Junction of C541 and R547 Rx port TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 182 123. If it has not, replace the main-board assembly and go to “Final Tasks” on page 123. Figure 11.13 Synthesizer circuitry under the can (VHF radio, bottom side) VCO BOT VCO BOT Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 183 123. If they are still not correct, go to Step Resolder R542 in position (see Figure 11.12). Replace the main- board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 184 If the voltages measured in Step 9 Step 11 are correct, go to Task 33. If they are not, the switching network is suspect; go to Task Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 185 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 186 “Final Tasks” on page 123. If they are not, or if no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 187: Power Supply For Fcl
The remaining three stages are covered in “VCXO and TCXO Outputs” “VCXO and CODEC Circuitry” respectively. The test and measurement points for diagnosing faults in the FCL are summarized in Figure 11.14. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 188 Figure 11.14 Test and measurement points the FCL circuitry Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 189 Task 3 “Power Supply Fault Finding” on page 132. Figure 11.15 TCXO circuitry under the CDC TOP can VIA FOR MEASURING 3 V DC SUPPLY IF TOP CAN TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 190: Vcxo And Tcxo Outputs
Confirm the removal of the fault and go to Task 36. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 191 Figure 11.16 FCL circuitry under and adjacent the FCL TOP can VIA FOR MEASURING VCXO OUTPUT POSITION IN WHICH TO PLACE R527 FOR FAULT-DIAGNOSIS PURPOSES WHEN LOOP OSCILLATES TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 192 “Final Tasks” on page 123. Figure 11.17 FCL circuitry under the VCXO BOT can CAN FOR SYN BOT CAN DIGITAL BOARD CDC BOT CAN Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 193: 11.10 Signals At Tp501 And Tp502
Confirm the removal of the fault and go to Task 38. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 194 Confirm the removal of the fault, and go to Task 39. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 195 If the signal is correct, the fault has been removed; go to “Final Tasks” on page 123. If the signal is not correct, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 196: 11.11 Vcxo And Codec Circuitry
CODEC 2 circuitry; go to Task If the voltage levels are all correct (following earlier repairs), the fault has been removed; go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 197 Replace all cans. Repeat Task 40 to confirm the removal of the fault. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Frequency Synthesizer Fault Finding © Tait Electronics Limited October 2005...
Page 198 Replace all cans. Repeat Task 40 to confirm the removal of the fault. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. Frequency Synthesizer Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 199: Receiver Fault Finding
Set transmit frequency (x in hertz) and receive frequency (y in hertz) to specified values Read tuning voltage for front-end circuitry — displays voltage x in millivolts Read signal power at output of channel filter — displays power x (square of amplitude) TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 200: Faulty Receiver Sensitivity
“Excessive Loss of Sensitivity” on page 204 (sensitivity is very low) x < 500 000, go to “Moderate or Slight Loss of Sensitivity” on page 208 (sensitivity is low) Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 201 Figure 12.1 Receiver circuitry under the can (top side) IF TOP B1 band Q404 Measurement point H5/H6 bands Q404 Measurement point TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 202: Excessive Loss Of Sensitivity
3. If it is not, the 3V RX switch (based on Q604 and Q605) in the PSU module is suspect; go to Task 3 “Power Supply Fault Finding” on page 132. Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 203 Figure 12.2 Receiver circuitry under the can (bottom side) B1 band H5/H6 bands Figure 12.3 Receiver circuitry under the can (top side) FE TOP Q401 Measurement point TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 204 Recalibrate the receiver using the calibration application. Confirm the removal of the fault, and go to “Final Tasks” on page 123. If the repair failed go to Task Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 205 Recalibrate the receiver using the calibration application. Confirm the removal of the fault, and go to “Final Tasks” on page 123. If the repair failed go to Task TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 206: Moderate Or Slight Loss Of Sensitivity
123. If they are not, go to Step if the receiver output level x measured in Go to Task 8 Task 1 was less than 40 000; otherwise go to Task Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 207 91 ± 15 134 ± 15 176 ± 15 210 ± 15 Voltage (V) 0.48 ± 0.24 1.07 ± 0.18 1.58 ± 0.18 2.07 ± 0.18 2.47 ± 0.18 TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 208 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 209: Incorrect Rssi Readings
2040 ± 40 2050 ± 40 AGC2 2200 ± 50 2220 ± 50 Receiver input power (dBm) Standard radio Trigger-base radio AGC0 –50 –44 AGC1 –60 –54 AGC2 –68 –62 TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 210 123. If it has not, go to Step In this case all the RSSI calibration settings are correct, but there is still an RSSI fault. Go to Task 1 and check the receiver sensitivity. Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 211: Faulty Radio Mute
If the setting is “Noise Level”, implying that noise muting is selected, 15. If the setting is “Signal Strength”, implying that RSSI go to Task muting is selected, go to Task TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 212 Channel spacing SINAD (dB) Minimum noise value Maximum noise value Narrow (12.5 kHz) 1900 2300 Medium (20 kHz) 3700 4200 1000 1500 Wide (25 kHz) 5000 7300 2200 3700 Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 213 Tasks” on page 123. If it has not, go to Task 10 and check the RSSI calibration. Figure 12.4 TCXO circuitry under the can (top side) CDC TOP TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 214: High Receiver Distortion
Task Check if the distortion fault has been removed. If it has, go to “Final Tasks” on page 123. If it has not, go to Task Receiver Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 215 Repair any fault, confirm the removal of the fault, and go to “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Receiver Fault Finding © Tait Electronics Limited October 2005...
Page 217 Set synthesizer on (x=1) or off (x=0) via DIG SYN EN line 335 x Set transmit-receive switch on (x=1) or off (x=0) via DIG SYN TR SW line TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 218 Can Replacement This applies to the B1, H5 and H6 bands. For certain other bands the transmitter will not operate correctly unless all the cans are fitted. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 219 Avoid RF burns. Do not touch the antenna or the RF signal path on the circuit board while the transmitter is operating. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 220 TEST POINT SUPPLY +13V8 BATT SIGNAL TYPES SWITCH ANALOG AGND INTERFACE L310 L306 CIRCUITRY TEST POINT TEST POINT OTHER FRE- TRANS- QUENCY EXCITER DRIVER MITTER SYNTHE- CIRCUITRY SIZER Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 221 Enter the CCTM command 32 to place the radio in receive mode. If the power supply measured in Step 7 Step 8 is not correct, go Task 2. If it is, go to Task TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 222 Figure 13.2 Point for measuring the power supply to the PAs B1 BAND MEASUREMENT POINT ON L310 (B1 BAND SIMILAR) H5, H6 BANDS Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 223 B1 band Measurement point on L306 Measurement point on R339 Point 1 on R350 Point 2 on R350 H5/H6 bands Measurement point on L306 Measurement point on R339 TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 224 230. If it is not, the 9V regulator IC601 and the associated switching circuitry Q603 are suspect; go to Task 3 “Power Supply Fault Finding” on page 132. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 225 D TX INH TEST POINT REV PWR TEST POINT TX INH TEST POINT FWD PWR TEST POINT IF TOP CAN 9V0 TX TEST POINT GND TEST POINT TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 226: Transmitter Fault Finding (25W)
Table 13.3 Voltages in millivolts corresponding to nominal forward and reverse powers Frequency band Forward power (318 command) Reverse power (319 command) 1100 to 2000 < 500 2500 to 3500 < 1000 2800 to 3900 < 1000 Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 227 Figure 13.5 Measurement and test points for diagnosing faults concerning the transmitter RF power TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 228 If the reverse power is momentarily too high, the directional coupler, PIN switch or LPF is suspect; go to Task 29. Otherwise go to Task Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 229 Low (> 0.5A) Task 29 — Check power at directional coupler None at RF connector (< 0.1W) None (< 0.5A) Task 7 — Check for inhibiting of transmitter TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 230 The normal lock status is 110. If it is not, proceed to the relevant section. If it is, go to Step Check for short circuits on the line from the test DIG TX INH D TX INH point. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 231 343. If a fault is found, repair it, confirm the removal of the fault, and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 232 PA circuitry under the can and part of the directional coupler under the DIRC TOP PAF TOP can (B1 band) Temperature sensor Mounting point for test capacitor Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 233 PAF TOP DIRC TOP can (H5 and H6 bands) Temperature sensor Mounting point for test capacitor Test pad TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 234 Task 31 — the PIN switch and LPF require checking. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 235 If the power and current are now correct at all three frequencies, the fault has been rectified; go to “Final Tasks” on page 123. If they are not, go to Task 25 “RF Signal Path” on page 259. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 236 29 ± 5W 34 ± 5W 29 ± 5W 5 ± 5W 12 ± 5W 27 ± 5W 13 ± 5W 19 ± 5W 28 ± 5W Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 237: Biasing Of Pa Driver And Pas
Note the current reading on the DC power supply. This will be less than 500mA. With the radio still in transmit mode, check the biasing of the PAs and PA driver, beginning with Task TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 238 Figure 13.8 Measurement and test points for diagnosing faults in the biasing of the PAs and PA driver Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 239 Table 13.6 Gate biases for the PAs and PA driver at high power Offset currents in mA Frequency band First PA Second PA PA driver 1000 1000 1000 1000 TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 240 VCO TOP CAN (UHF ONLY) DIRC TOP CAN SET PWR TEST POINT DRV TEST POINT FWD PWR TEST POINT IF TOP CAN PWR TEST POINT FIN1 TEST POINT FIN2 TEST POINT Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 241 “Final Tasks” on page 123. If the repair failed or Q310 itself is faulty, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 242 VIA TO PIN 14 OF IC301 VIA TO GATE OF Q309 VIA TO PIN 8 OF IC301 VIA TO GATE OF Q310 H5, H6 BANDS PAF TOP Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 243 “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 244 17. If neither the current nor the voltage is correct, go to Task Enter the CCTM command 332 1 to switch off final bias 2, and go to Task Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 245 “Final Tasks” on page 123. If the repair failed or Q309 itself is faulty, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 246 “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 247 20. If it does not, go to Step Enter the CCTM command 32 to place the radio in receive mode, and go to “CODEC and Audio Fault Finding” on page 343. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 248 If the voltage is correct, replace Q306; confirm the removal of the fault and go to “Final Tasks” on page 123. If it is not, go to Task Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 249 Figure 13.11 PA driver circuitry under the PAD TOP B1 band Components C310, R324, R327 Gate of Q306 H5/H6 bands Components C310, R324, R327 Gate of Q306 TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 250 If the voltage at the test point increases as required, go to Task 22. If it does not, go to “CODEC and Audio Fault Finding” on page 343. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 251 Figure 13.12 Circuitry under the DIRC TOP B1 band H5/H6 bands TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 252 13.13), and then go to Step Repair any fault revealed by the above checks. Replace IC303 if none of the other components is faulty (see Figure 13.9). Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 253 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 254 Figure 13.13 Components of concern on the bottom-side of the main board B1 band H5/H6 bands Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 255 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 256: Rf Signal Path
LEAD TO DRAIN OF Q306 AT C313 TEST SET FRE- DIREC- QUENCY TIONAL SYNTHE- COUPLER SIZER RECEIVER SWITCH TEST CAPACITOR TEST LEAD TO TEST SET RF CON- NECTOR Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 257 Check C300 (see Figure 13.15). If C300 is not faulty, go to “Frequency Synthesizer Fault Finding” on page 143. If C300 is faulty, replace it and return to Step TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 258 Exciter output at C301 Synthesizer output at C300 Buffer output at C313 H5/H6 bands Driver output Exciter output at C301 Synthesizer output at C300 Buffer output at C313 Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 259 8.6 ± 0.5 0.2 ± 0.1 0.3 ± 0.1 3.6 ± 0.5 8.2 ± 0.5 0.2 ± 0.1 0.3 ± 0.1 3.2 ± 0.5 2.5 ± 0.5 TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 260 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 261 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 262 Figure 13.16 Components of the interstage matching circuitry between the PA driver Q306 and the PAs Q309 and Q310 B1 band H5/H6 bands PAF TOP can PAD TOP can Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 263 If the power measured in both the above cases exceeds 35W, go to Step 14. If it does not, go to Task Remove the test lead and test capacitor, resolder the coupling capacitors in position, and go to Task TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 264 “Final Tasks” on page 123. If it is not, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 265 PIN switch is suspect; go to Task Remove the test lead and test capacitor, resolder the blocking capacitors in position, and go to Task TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 266 Figure 13.17 Circuitry under the can, and points for attaching the test lead and test capacitor PIN TOP B1 band H5/H6 bands Test pad Mounting point for test capacitor Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 267 “Final Tasks” on page 123. If it is not, the repair failed: replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 268 Figure 13.18 Components of concern on the bottom-side of the main board COPPER PLATE VCO BOT CAN NB BOT CAN B1 BAND COPPER PLATE VCO BOT CAN H5, H6 BANDS Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 269 Figure 13.19 Circuitry under the can (top side) LPF TOP B1 band H5/H6 bands TB7100 Service Manual Transmitter Fault Finding (25W) © Tait Electronics Limited October 2005...
Page 270 “Final Tasks” on page 123. If it does not, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (25W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 271: Transmitter Fault Finding (50W/40W)
Set synthesizer on (x=1) or off (x=0) via DIG SYN EN line 335 x Set transmit-receive switch on (x=1) or off (x=0) via DIG SYN TR SW line TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 272 Replace all cans that have been removed only after repairing the board. Can Replacement An exception is the B1 band, however, where the can must be in LPF TOP place if the transmitter is to operate correctly. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 273 Avoid RF burns. Do not touch the antenna or the RF signal path on the circuit board while the transmitter is operating. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 274: Power Supplies
TEST POINT SUPPLY +13V8 BATT SIGNAL TYPES SWITCH ANALOG AGND INTERFACE L310 L306 CIRCUITRY TEST POINT TEST POINT OTHER FRE- TRANS- QUENCY DRIVER EXCITER MITTER SYNTHE- CIRCUITRY SIZER Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 275 Enter the CCTM command 32 to place the radio in receive mode. If the power supply measured in Step 7 Step 8 is not correct, go Task 2. If it is, go to Task TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 276 Figure 14.2 Point for measuring the power supply to the PAs (B1 band) MEASUREMENT POINT ON L310 PAF TOP Q310 Q309 B1 BAND Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 277 Figure 14.3 Point for measuring the power supply to the PAs (H5 and H7 bands) MEASUREMENT POINT ON L310 PAF TOP L310 Q310 Q309 H5, H7 BANDS TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 278 Point for measuring the power supply to the PA driver (B1 band) POINT 2 ON R350 MEASUREMENT POINT ON R339 R339 R350 PAD TOP MEASUREMENT POINT ON L306 POINT 1 ON R350 Q306 B1 BAND Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 279 Point for measuring the power supply to the PA driver (H5 and H7 bands) POINT 2 ON R 350 MEASUREMENT POINT ON R339 R339 R350 PAD TOP MEASUREMENT POINT ON L306 POINT 1 ON R350 Q306 H5, H7 BANDS TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 280 Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 281 287. If it is not, the 9V regulator IC601 and the associated switching circuitry Q603 are suspect; go to Task 3 “Power Supply Fault Finding” on page 132. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 282 Figure 14.6 Test points for checking the 9V supply, the forward and reverse RF power, and the inhibiting of the transmitter Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 283: Transmitter Rf Power
Table 14.3 Voltages in millivolts corresponding to nominal forward and reverse powers Frequency band Forward power (318 command) Reverse power (319 command) 2600 to 3400 < 500 3200 to 3900 < 700 3300 to 4000 < 900 TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 284 Figure 14.7 Measurement and test points for diagnosing faults concerning the transmitter RF power Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 285 If the reverse power is momentarily too high, the directional coupler, PIN switch or LPF is suspect; go to Task 31. Otherwise go to Task TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 286 Low (> 0.5A) Task 31 — Check power at directional coupler None at RF connector (< 0.1W) None (< 0.5A) Task 7 — Check for inhibiting of transmitter Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 287 326 4 326 3 326 2 326 1 The above measurements should confirm that the power remains unchanged at all settings. Carry out Task 12 and then Task TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 288 “Final Tasks” on page 123. If the repair failed or no fault could be found, replace the main-board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 289 343. If a fault is found, repair it, confirm the removal of the fault, and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly, and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 290 DIRC TOP PAF TOP can (B1 band) Q310 Q309 D301 TEMPERATURE SENSOR MOUNTING POINT FOR TEST CAPACITOR B1 BAND TEST PAD Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 291 PAF TOP DIRC TOP can (H5 and H7 bands) Q310 Q309 D301 TEMPERATURE SENSOR MOUNTING POINT FOR TEST CAPACITOR H5, H7 BANDS TEST PAD TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 292 Task 33 — the PIN switch and LPF require checking. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 293 If the power and current are now correct at all three frequencies, the fault has been rectified; go to “Final Tasks” on page 123. If they are not, go to Task 26 “RF Signal Path” on page 321. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 294 38 ± 5W 48 ± 5W 33 ± 5W 16 ± 5W 17 ± 5W 21 ± 5W 25 ± 5W 32 ± 5W 40 ± 5W Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 295: Biasing Of Pa Driver And Pas
Note the current reading on the DC power supply. This will be less than 500mA. With the radio still in transmit mode, check the biasing of the PAs and PA driver, beginning with Task TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 296 Figure 14.10 Measurement and test points for diagnosing faults in the biasing of the PAs and PA driver Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 297 Table 14.6 Gate biases for the PAs and PA driver at high power Offset currents in mA Frequency band First PA Second PA PA driver 1690 1690 1800 1800 1800 1800 TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 298 DRV TEST POINT R333 R336 IC303 REV PWR TEST POINT FIN2 TEST POINT FIN1 TEST POINT FWD PWR TEST POINT B1 BAND PWR TEST POINT IF TOP CAN Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 299 FIN1 TEST POINT IC303 FIN2 TEST POINT REV PWR TEST POINT DRV TEST POINT FWD PWR TEST POINT H5, H7 BANDS PWR TEST POINT IF TOP CAN TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 300 “Final Tasks” on page 123. If the repair failed or Q310 itself is faulty, replace the main- board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 301 IC301 AND PAs B1 BAND VIA TO PIN 14 OF IC301 VIA TO GATE OF Q309 VIA TO PIN 8 OF IC301 VIA TO GATE OF Q310 TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 302 IC301 AND PAs H5, H7 BANDS VIA TO PIN 14 OF IC301 VIA TO GATE OF Q309 VIA TO PIN 8 OF IC301 VIA TO GATE OF Q310 Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 303 “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 304 17. If neither the current nor the voltage is correct, go to Task Enter the CCTM command 332 1 to switch off final bias 2, and go to Task Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 305 “Final Tasks” on page 123. If the repair failed or Q309 itself is faulty, replace the main- board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 306 “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 307 20. If it does not, go to Step Enter the CCTM command 32 to place the radio in receive mode, and go to “CODEC and Audio Fault Finding” on page 343. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 308 If the voltage is correct, replace Q306; confirm the removal of the fault and go to “Final Tasks” on page 123. If it is not, go to Task Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 309 Figure 14.15 PA driver circuitry under the can (B1 band) PAD TOP PAD TOP COMPONENTS C310, R324 AND R327 R327 C310 R324 Q306 GATE OF Q306 B1 BAND TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 310 Figure 14.16 PA driver circuitry under the can (H5 and H7 bands) PAD TOP COMPONENTS C310, R324 AND R327 PAD TOP R324 C310 Q306 GATE OF Q306 H5, H7 BANDS Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 311 If the voltage at the test point increases as required, go to Task 22. If it does not, go to “CODEC and Audio Fault Finding” on page 343. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 312 Figure 14.17 Circuitry under the DIRC TOP B1 band H5/H7 bands Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 313 LPF or both are suspect; go to Task 33. If there is a fault, go to Step In the buffer amplifiers, check R340 and R341 (see Figure 14.11, Figure 14.18 Figure 14.19). TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 314 Figure 14.18 Components of concern on the bottom-side of the main board (B1 band) COPPER PLATE VCO BOT CAN C319 R396 D311 B1 BAND NB BOT CAN D TX INH TEST POINT Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 315 Figure 14.19 Components of concern on the bottom-side of the main board (H5 and H7 bands) COPPER PLATE VCO BOT CAN R396 R340 H5, H7 BANDS TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 316 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 317 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 318: Rf Signal Path
DRAIN OF Q306 AT C3509 AT C3505 TEST SET FRE- DIREC- QUENCY TIONAL SYNTHE- COUPLER SIZER RECEIVER SWITCH TEST CAPACITOR TEST LEAD TO TEST SET RF CON- NECTOR Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 319 14.22). If C3500 is not Figure 14.21 Figure faulty, go to “Frequency Synthesizer Fault Finding” on page 143. If C3500 is faulty, replace it and return to Step TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 320 OUTPUT OF STAGE 2 OF EXCITER AT C3509 Q3505 R3525 C3509 B1 BAND FCL TOP CAN OUTPUT OF STAGE 1 OF EXCITER AT C3505 SYNTHESIZER OUTPUT AT C3500 Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 321 OUTPUT OF STAGE 2 Q3505 OF EXCITER AT C3509 R3525 H5, H7 BANDS FCL TOP CAN OUTPUT OF STAGE 2 OF EXCITER AT C3505 SYNTHESIZER OUTPUT AT C3500 TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 322 2.4 ± 0.2 2.7 ± 0.5 6.8 ± 0.5 7.3 ± 0.5 0.3 ± 0.1 1.1 ± 0.2 2.1 ± 0.5 4.8 ± 0.5 5.3 ± 0.5 Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 323 1.0 ± 0.2 1.9 ± 0.5 3.4 ± 0.5 4.8 ± 0.5 0.2 ± 0.1 1.2 ± 0.2 0.9 ± 0.5 2.4 ± 0.5 2.8 ± 0.5 TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 324 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 325 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 326 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 327 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 328 Figure 14.23 Components of the interstage matching circuitry between the PA driver Q306 and the PAs Q309 and Q310 (B1 band) Q310 Q306 Q309 B1 BAND PAF TOP CAN PAD TOP CAN Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 329 Figure 14.24 Components of the interstage matching circuitry between the PA driver Q306 and the PAs Q309 and Q310 (H5 and H7 bands) Q310 Q306 Q309 H5, H7 BANDS PAF TOP CAN PAD TOP CAN TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 330 60W (H5, H7), go to Step 14. If it does not, go to Task Remove the test lead and test capacitor, resolder the coupling capacitors in position, and go to Task Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 331 DIRC TOP capacitor B1 band H5/H7 bands Mounting point for test capacitor Test pad Test pad TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 332 “Final Tasks” on page 123. If it is not, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 333 14. If it does not, the circuitry of the PIN switch is suspect; go to Task Remove the test lead and test capacitor, resolder the blocking capacitors in position, and go to Task TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 334 PIN TOP TEST PAD TEST PAD MOUNTING POINT FOR TEST CAPACITOR D307 D3507 B1 BAND H5, H7 BANDS Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 335 “Final Tasks” on page 123. If it is not, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 336 Figure 14.27 Components of concern on the bottom-side of the main board (B1 band) COPPER PLATE VCO BOT CAN B1 BAND NB BOT CAN Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 337 Figure 14.28 Components of concern on the bottom-side of the main board (H5 and H7 bands) COPPER PLATE VCO BOT CAN R3000 H5, H7 BANDS TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 338 Figure 14.29 Circuitry under the LPF TOP B1 BAND H5, H7 BANDS Transmitter Fault Finding (50W/40W) TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 339 (H5, H7), the fault has been rectified; go to “Final Tasks” on page 123. If it does not, the repair failed; replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual Transmitter Fault Finding (50W/40W) © Tait Electronics Limited October 2005...
Page 341: Codec And Audio Fault Finding
324 x y Output audio signal at tap point x of tap type y to AUD TAP OUT 400 x Select channel with channel number x TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 342: Power Supplies
3. If it is not, go to Step The 3V regulator IC603 is suspect (see Figure 15.1). Check the regulator as described in Task 3 “Power Supply Fault Finding” on page 132. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 343 Figure 15.1 Power-supply circuitry for the CODEC and audio circuitry under the CDC BOT LO2 BOT CAN CAN FOR DIGITAL BOARD TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 344 “Faulty Modulation” (distorted or no transmit modulation) “Faulty Modulation Using Auxiliary Connector” (modulation at auxiliary connector only) Further details are given in the introduction to the section. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 345: Faulty Speaker Audio
The next section deals with the case where there is no speaker audio at the auxiliary connector. Figure 15.2 Circuitry in the vicinity of IC202 (top side) TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 346 5. If they are not, check the programming and test set-up; otherwise the digital board is faulty; replace the main-board assembly and go to “Final Tasks” on page 123. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 347 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 348 Figure 15.3 Circuitry under the can, and adjacent interface circuitry CDC TOP CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 349 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 350 Figure 15.4 Circuitry under the CDC BOT CDC AUD TAP OUT JUNCTION OF R218 AND IC204 LO2 BOT CAN CAN FOR DIGITAL BOARD CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 351 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 352: No Speaker Audio At Auxiliary Connector
These tasks need to be followed by those of “Faulty Modulation Using Auxiliary Connector” on page 366 if there is also a fault with the transmit modulation using the auxiliary connector. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 353 Task 15 “Faulty Modulation Using Auxiliary Connector” on page 366. If there is no other fault, go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 354 Figure 15.6 Circuitry in the vicinity of the auxiliary connector (bottom side) AUXILIARY CONNECTOR SK101 CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 355 “Faulty Modulation Using Auxiliary Connector” on page 366. If there is no other fault, go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 356 Figure 15.7 Circuitry under the CDC BOT CAN FOR DIGITAL BOARD LO2 BOT CAN JUNCTION OF R224 AND IC204 CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 357: Faulty Receiver
“Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 358 Figure 15.8 Circuitry in the vicinity of the CDC TOP B1 band Junction of C708 and C732 H5/H6 bands Junction of C708 and C732 CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 359 “Receiver Fault Finding” on page 201. Either the digital board or CODEC 1 (IC204) is faulty; replace the main-board assembly and go to “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 360: Faulty Modulation
If the above voltage is correct, go to Task 14; the bias network is suspect. If it is not, go to Task 13; the 2.3V supply is suspect. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 361 Figure 15.9 Circuitry in under the CDC BOT LO2 BOT CAN CAN FOR DIGITAL BOARD TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 362 “Final Tasks” on page 123. If the repair failed or the fault could not be found, replace the main-board assembly and go to “Final Tasks” on page 123. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 363 Figure 15.10 Circuitry under the CDC TOP JUNCTION OF R229 AND R232 ITF AUD TAP IN JUNCTION OF R237 AND R241 TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 364: Faulty Modulation Using Auxiliary Connector
Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. CODEC and Audio Fault Finding TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 365 Confirm the removal of the fault and go to “Final Tasks” on page 123. If the repair failed, replace the main-board assembly and go “Final Tasks” on page 123. TB7100 Service Manual CODEC and Audio Fault Finding © Tait Electronics Limited October 2005...
Page 367: Spare Parts
Figure 7.1 Hexagonal screwlock fastener (D-range connectors) 354-01043-xx Figure 7.1 Nut M3 Nyloc (N-type connectors) 352-00010-xx Figure 7.1 Earthing terminal 356-00010-xx Figure 7.1 Heatsink for audio PA 303-13152-xx Figure 7.3 TB7100 Service Manual Spare Parts © Tait Electronics Limited October 2005...
Page 368 The characters xx in an IPN stand for the issue number. Items will always be the latest issue at the time the radio is manufactured. The characters yy in an IPN or spares kit number stand for the abbreviated frequency band. For more information, refer to “Frequency Bands” on page Spare Parts TB7100 Service Manual © Tait Electronics Limited October 2005...
Page 369: Tait General Software Licence Agreement
MERGED INTO ANOTHER PROGRAM WILL AUTOMATICALLY AND WITHOUT NOTICE FROM CONTINUE TO BE SUBJECT TO THE TERMS AND TAIT IN THE EVENT THAT THE LICENSEE FAILS TO CONDITIONS OF THIS AGREEMENT COMPLY WITH ANY TERM OR CONDITION OF THE LICENSEE MAY NOT DUPLICATE...
Page 370: Limited Warranty
THAT SUBJECT ONLY TO ANY EXPRESS WRITTEN OR OTHERWISE AT LAW FOR ANY LOSSES OR TERMS OF AGREEMENT TO THE CONTRARY DAMAGES WHETHER GENERAL SPECIAL BETWEEN TAIT AND THE LICENSEE THIS IS THE EXEMPLARY PUNITIVE DIRECT INDIRECT OR COMPLETE AND EXCLUSIVE STATEMENT OF THE...

Tait TB7100 Service Manual

Tait Contact Information

Preface

1 Introduction

2 Mechanical Design

3 Functional Description

4 Circuit Descriptions

5 Connections

6 General Information

7 Disassembly and Reassembly

8 Servicing Procedures

9 Power Supply Fault Finding

10 Interface Fault Finding

11 Frequency Synthesizer Fault Finding

12 Receiver Fault Finding

13 Transmitter Fault Finding (25W)

14 Transmitter Fault Finding (50W/40W)

15 CODEC and Audio Fault Finding

16 Spare Parts

Tait General Software Licence Agreement

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Summary of Contents for Tait TB7100

Table of Contents