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Commercial Series CP040 Radios Detailed Service Manual 6866549D19-B...
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Commercial Series CP040 Radios Detailed Service Manual 6866549D19-B Contents Section 1 Service Maintainability Section 2 Power Distribution and Controller Service Information Section 3 VHF1 Service Information Section 4 VHF2 Service Information Section 5 UHF1 Service Information Section 6 UHF2 Service Information...
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DOCUMENT HISTORY The following major changes have been implemented in this manual since the previous edition: Edition Description Date 6866549D19-O Initial edition Dec. 2003 6866549D19-A Added VHF 1 Band information. Oct. 2004 6866549D19-B - In the Service Maintainability Section: May 2008 Chapter 1, Updated Technical Support contact information.
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Commercial Series CP040 Radios Service Maintainability Issue: May 2008...
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Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
Read this information before using the radio. PRODUCT SAFETY AND RF EXPOSURE FOR PORTABLE TWO-WAY RADIOS. This document provides information and instructions for the safe and efficient operation of Motorola Portable Two-Way Radios. The information provided in this document supersedes information contained in user guides published prior to February 2002.
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Compliance with RF Exposure Standards Your Motorola two-way radio is designed and tested to comply with a number of national and International standards and guidelines (listed below) for human exposure to radio frequency electromagnetic energy. This radio complies with the IEEE (FCC) and ICNIRP exposure limits for occupational/controlled RF exposure environments at operating duty factors of up to 50% talk- 50% listen and is authorized by the IEEE/ICNIRP for occupational use only.
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- approved antennas, batteries and accessories may exceed IEEE/ICNIRP RF expo- sure guidelines. For a list of Motorola-approved antennas, batteries, and other accessories please see your dealer or local Motorola contact. Your nearest dealer can be found at the following web site: http://www.motorola.com/cgiss/emea/dealerlocator.html Additional Information For additional information on exposure requirements or other training information, visit http://www.motorola.com/rfhealth...
ELECTROMAGNETIC INTERFERENCE/COMPATIBILITY NOTE: Nearly every electronic device is susceptible to electromagnetic interference (EMI) if inadequately shielded, designed or otherwise configured for electromagnetic compatibility. Facilities To avoid electromagnetic interference and/or compatibility conflicts, turn off your radio in any facility where posted notices instruct you to do so. Hospitals or health care facilities may be using equipment that is sensitive to external RF energy.
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OPERATIONAL WARNINGS Vehicles with an air bag Refer to vehicle manufacturer's manual prior to installation of electronic equipment to avoid interference with air bag wiring. WARNING: Do not place a portable radio in the area over an air bag or in the air bag deployment area.
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Warnings for Radios Approved as Intrinsically Safe Radios must ship from the Motorola manufacturing facility with the hazardous atmosphere capability and the intrinsic safety approval labelling (FM, UL, CSA, CENELEC or ATEX). Radios will not be upgraded to this capability and labeled once they have been shipped to the field.
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The manual PN referenced on the Intrinsically Safe Approval Label identifies the approved Accessories and or options that can be used with that portable radio unit. Using a non Motorola intrinsically safe battery and or accessory with the Motorola approved radio unit will void the intrinsically safe approval of that radio unit.
Table of Contents Chapter 1 INTRODUCTION 1.0 Scope of Manual ....................1-1 2.0 Warranty and Service Support................1-1 2.1 Warranty Period and Return Instructions ............1-1 2.2 After Warranty Period ..................1-1 2.3 European Radio Support Centre (ERSC)............1-2 2.4 Parts Identification and Ordering ..............1-2 2.5 EMEA Test Equipment Support..............1-2 2.6 Technical Support...................1-3 2.7 Related Documents ..................1-3...
In instances where the product is covered under a "return for replacement" or "return for repair" warranty, a check of the product should be performed prior to shipping the unit back to Motorola. This is to ensure that the product has been correctly programmed or has not been subjected to damage outside the terms of the warranty.
Aftermarket and Accessory Division (AAD). If no part number is assigned, the part is not normally available from Motorola. If the part number is appended with an asterisk, the part is serviceable by Motorola Depot only. If a parts list is not included, this generally means that no user-serviceable parts are available for that kit or assembly.
Warranty and Service Support Technical Support Motorola Product Services is available to assist the dealer/distributors in resolving any malfunctions which may be encountered. North Europe - Stephen Woodrow Central and East Europe - Siggy Punzenberger Telephone: +44 (0) 1256 488 082...
INTRODUCTION Radio Model Information The model number and serial number are located on a label attached to the back of your radio. You can determine the RF output power, frequency band, protocols, and physical packages. The example below shows one mobile radio model number and its specific characteristics. Table 1-1 Radio Model Number (Example: MDH50KDC9AA2_N) Type of Model...
Chapter 2 MAINTENANCE Introduction This chapter of the manual describes: ■ preventive maintenance ■ safe handling of CMOS devices ■ repair procedures and techniques Preventive Maintenance The radios do not require a scheduled preventive maintenance program; however, periodic visual inspection and cleaning is recommended. Inspection Check that the external surfaces of the radio are clean, and that all external controls and switches are functional.
Equipment (WEEE) Directive 2002/96/EC and Restriction of Hazardous Subtances (ROHS) Directive 2002/95/EC). To maintain product compliance and reliability, use only the Motorola specified parts in this manual. For the identification of lead (Pb) free assemblies, all EPP products will carry the EPP Marking, shown below, on the printed circuit board (PCB).
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When damaged parts are replaced, identical parts should be used. If the identical replacement component is not locally available, check the parts list for the proper Motorola part number and order the component from the nearest Motorola Communications parts center listed in the “Piece Parts”...
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MAINTENANCE Once solder wicks onto the new component, remove the heat from the solder. Heat the remaining pad with the soldering iron and apply solder until it wicks to the component. If necessary, touch up the first side. All solder joints should be smooth and shiny.
(pF) or microfarads (µF), and inductance values are in nanohenries (nH) or microhenries (µH). DC voltages are measured from point indicated to chassis ground using a Motorola DC multimeter or equivalent. If the board has been removed from the chassis, the transmitter module mounting screws may be used for ground connection.
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MAINTENANCE Circuit Block Interconnection Legend: Name Description USWB+ Unswitched Battery Voltage (always on) 5 volts (regulated) 5 volts in RX mode only 5 volts in TX mode only RESET Low-line reset signal from U320 to uP D3_3V Digital 3.3 volts (regulated) Analog 3 volts (regulated) TX_ENA Transmit enable signal from uP to transmitter...
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Speaker and Microphone Schematic MATES WITH J470 ON RADIO BOARD MATES WITH J491 ON RADIO BOARD Figure 1-2. Speaker and Microphone Schematic Speaker and Microphone Parts List Reference Motorola Part Description Designator 5080258E16 Microphone, electret 5005679X04 Speaker assembly with connector...
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MAINTENANCE THIS PAGE INTENTIONALLY LEFT BLANK...
Table 3.2 lists the service aids recommended for working on the radio. While all of these items are available from Motorola, most are standard workshop equipment items, and any equivalent item capable of the same performance may be substituted for the item listed.
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SERVICE AIDS Table 3-2 Service Aids Motorola Part Description Application 5886564Z01 RF Adaptor Adapts radio’s antenna port to BNC cabling of test equipment. 0180305K08 Shop Battery Eliminator Interconnects radio to power supply. EPN4040 Wall-Mounted Power Supply Used to supply power to the RIB (UK).
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SERVICE AIDS 25 pin Male D Connector Components molded inside 2.5mm stereo and 3.5mm Orange 3.5mm Tip (Speaker +) Blue 3.5mm To Test Box Sleeve White 2.5mm Tip (Microphone) 1UF,16V 5% Spiral 2.5mm Yellow 2.5mm Center 25 pin Female D Connector To Test Box 3.5mm mono 2.5mm stereo...
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Commercial Series CP040 Radios Power Distribution and Controller Service Information Issue: May 2008...
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Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
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Table of Contents Chapter 1 THEORY OF OPERATION 1.0 Overview......................1-1 2.0 Radio Power Distribution ..................1-1 3.0 Controller Circuits ....................1-3 3.1 General ......................1-3 3.2 Microprocessor Circuitry ................1-4 3.3 Audio Circuitry....................1-8 Chapter 2 TROUBLESHOOTING CHARTS 1.0 Troubleshooting Flow Chart for Board and IC Signals (includes Controller, DC Regulation and Audio) ..........
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Chapter 1 THEORY OF OPERATION Overview This Chapter provides a detailed theory of operation for the controller circuits in the radio. The components of these circuits are contained on the Main Board. Refer to the RF sections of this manual for the component location details and the parts lists of the Controller Circuits. Radio Power Distribution Accessories 20 pin Connector...
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THEORY OF OPERATION When the radio is turned on, SWB+ is present and is applied to: ■ transistor switch Q494 (pins 1 and 6) which turns on Q493 ■ RX audio power amplifier U490 ■ voltage divider R420/R421 and port PE0, a microprocessor A/D input which measures battery voltage and radio on/off status The output of FET switch Q493 is applied to the control pins of regulators U310, U320 and U330, turning them on.
Controller Circuits Controller Circuits General The controller board is the central interface between the various subsystems of the radio. It provides the following functions: ■ interface with controls and indicators ■ serial bus control of major radio circuit blocks ■ encoding and/or decoding of selective signaling formats such as PL, DPL, MDC1200 and QuikCall II ■...
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THEORY OF OPERATION Microprocessor Circuitry The microprocessor circuitry includes microprocessor (U401) and associated EEPROM and Flash ROM memories. The following memory IC's are used: Table 1-2 Radio Memory Requirements Reference No. Description Type Size U402 Serial EEPROM AT25128 16K x 8 U403 Static RAM (not used)
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PD5 (U401 pin 2) for the audio filter IC ■ port PH0 (U401 pin 47) for the synthesizer IC ■ port PH4 (U401 pin 43) for the option board/display enable (not used in CP040) ■ port PD6 (U401 pin 3) for the serial EEPROM 3.2.4...
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THEORY OF OPERATION 3.2.6 Sensing of Externally-Connected Accessories Port PJ1 is used to detect the presence of externally connected accessories. Port PJ1 (U401 pin 72) is normally low, unless accessories (lapel speaker microphone, lightweight headset, etc.) are used with the radio. This port is used to detect an accessory PTT or auto sensing of a VOX accessory.
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Controller Circuits 3.2.9 Microprocessor 7.3975 MHz Clock The 7.3975 MHz clock signal (uP_CLK) is provided from the ASFIC_CMP (U451 pin 28). Upon startup the 16.8MHz crystal provides the signal to the ASFIC_CMP, which sends out the uP_CLK at 3.8MHz until a steady-state condition is reached and the clock is increased to 7.3975MHz for the microprocessor.
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(U510-1 and -2) for UHF models using low-side first injection. The gain of the buffer is 1.5 times or 3.5 dB. U480 and associated components are not used in CP040. Stage U480-1 is bypassed by jumper R487.
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The Motorola RLN4460 Portable Test Set and PMKN4004 Programming Test Cable provide the proper interface between the radio's ungrounded audio output and ground-referenced test equipment.
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1-10 THEORY OF OPERATION 3.3.6 Battery Charging Through Microphone Jack A wall-type charging power supply may be connected to the 2.5 mm microphone jack (part of accessory connector J451). The voltage present at the tip contact (pin 4) is applied to the center charging contact of the battery via diode D470.
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Chapter 2 TROUBLESHOOTING TABLES Troubleshooting Tables for Board and IC Signals (includes Controller, DC Regulation and Audio) This section contains detailed troubleshooting tables. These tables should be used as a guide in determining the problem areas. They are not a substitute for knowledge of circuit operation and astute troubleshooting techniques.
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Troubleshooting Tables for Board and IC Signals (includes Controller, DC Regulation and Audio) IC Designator Pin Function DC Voltage Comments (Condition) U110 RF input (TX mode) RF Power Amp Vgg (gate bias) 2.65 (typ) (TX mode) (4.25V typ at VHF) 6.59 (TX mode) RF output...
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TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U201 Ref osc XTAL2 Freq Synthesizer Ref osc warp output 3.00 Superfilter cap 4.48 Superfilter base (NU) 3.76 Superfilter output 4.52 Superfilter input 4.96 Prescaler input 1.97 Prescaler ground Prescaler Vdd 2.99 Prescaler Vref (NU) 1.97...
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Troubleshooting Tables for Board and IC Signals (includes Controller, DC Regulation and Audio) IC Designator Pin Function DC Voltage Comments (Condition) U251 Prescaler output 2.26 VCO / Buffer TX switch output (NU) 0.06 Vcc_BUFFERS 3.00 TX VCO emitter (RX mode) TX VCO base (RX mode) GND_LOGIC...
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TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 PD4_SCK serial clock input Microprocessor PD5_SS 3.23 ASFIC chip select PD6_VLIN 3.23 EEPROM chip select PG7_R_W 3.21 PG6_AS 3.23 PG0_XA13 3.23 PB7_ADDR15 0.026 PB6_ADDR14 0.028 PB3_ADDR11 3.06 PB1_ADDR9 3.05 PB2_ADDR10 0.16 3.23...
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Troubleshooting Tables for Board and IC Signals (includes Controller, DC Regulation and Audio) IC Designator Pin Function DC Voltage Comments (Condition) U401 PH7_CSPROG 3.05 Microprocessor VDDL 3.23 VSSL PH6_CSGP2 3.23 PH5_CSGP1 3.23 PH4_CSIO PH3_PW4 3.21 On/off control output PH2_PW3 PH1_PW2 3.00 PH0_PW1 3.23...
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TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 3.23 Microprocessor 3.23 Bottom option button 3.23 Top option button PA0_IC3 PA1_IC2 1.57 PA2_IC1 3.00 PA3_IC4_OC5_OC1 3.00 PA4_OC4_OC1 Squelch detect input PA5_OC3_OC1 Channel activity input PA6_OC2_OC1 PA7_PA1_OC1 VSSR VDDR 3.23 ECLK (NU) 1.60...
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Troubleshooting Tables for Board and IC Signals (includes Controller, DC Regulation and Audio) IC Designator Pin Function DC Voltage Comments (Condition) U404 3.06 Flash ROM 3.08 3.05 0.13 0.31 3.17 EN_WE 3.21 From U401-4 3.23 RESET 3.20 U404 3.17 Flash ROM 0.30 0.22 3.03...
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2-10 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U451 VDD for analog circuits 3.00 ASFIC_CMP DISC audio input 1.34 From U510 Ground for analog circuits DACU output DACR output DACG output 2.38 (typ) Power set (TX mode) VOX peak detector output 2.91 PLCAP for DC integrator...
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Troubleshooting Tables for Board and IC Signals (includes Controller, DC Regulation and Audio) 2-11 IC Designator Pin Function DC Voltage Comments (Condition) U451 GCB5 general purpose output ASFIC_CMP RX audio send to option 1.48 Modulation output 1.50 To U201-10 RX audio out to power amp 1.51 Flat TX audio return from option 0.20...
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Chapter 3 CONTROLLER SCHEMATICS Allocation of PCBs and Schematic Diagrams The Controller circuits are contained on the printed circuit board (PCB) containing the RF circuits. This Chapter shows the schematics for the Controller circuits only, refer to the relevant RF section for details of the related RF circuits, the PCB component layouts and the complete radio parts lists.
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Commercial Series CP040 Radios VHF1 (136-162MHz) Service Information Issue: May 2008...
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Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
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Table of Contents Chapter 1 THEORY OF OPERATION 1.0 Introduction ......................1-1 2.0 VHF1 (136-162MHz) Receiver................1-1 2.1 Receiver Front-End ..................1-2 2.2 Receiver Back-End..................1-3 3.0 VHF1 (136-162MHz) Transmitter.................1-4 3.1 Transmitter Power Amplifier ................1-4 3.2 Antenna Switch....................1-4 3.3 Harmonic Filter ....................1-5 3.4 Antenna Matching Network ................1-5 3.5 Power Control....................1-5 4.0 VHF1 (136-162MHz) Frequency Generation Circuitry.........1-6 4.1 Fractional-N Synthesizer ................1-7...
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Chapter 1 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the VHF circuits in the radio. Schematic diagrams and board layout diagrams are included in Chapter 4 in this Section of the manual. VHF1 (136-162MHz) Receiver The VHF receiver covers the range of 136-162 MHz and provides switchable IF bandwidth for use with 20/25 kHz or 12.5 kHz channel spacing systems.
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THEORY OF OPERATION Receiver Front End Incoming RF signals from the antenna are first routed through the harmonic filter and antenna switch, part of the transmitter circuitry, before being applied to the receiver front end. The receiver front end consists of a preselector filter, RF amplifier, an interstage filter, and a double-balanced first mixer.
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VHF1 (136-162MHz) Receiver Receiver Back End The receiver back end is a dual conversion design. High IF selectivity is provided by FL51, a 4-pole fundamental mode 44.85 MHz crystal filter with a minimum 3 dB bandwidth of + 6.7 kHz, a maximum 20 dB bandwidth of ±12.5 kHz, and a maximum insertion loss of 3.5 dB.
THEORY OF OPERATION VHF Transmitter The VHF transmitter covers the range of 136-162 MHz. Depending on model, the output power of the transmitter is either switchable on a per-channel basis between high power (5 watts) and low power (1 watt), or is factory preset to 2 watts. The transmitter is divided into four major blocks as shown in Figure 2-2.
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VHF Transmitter Harmonic Filter The harmonic filter consists of components C130-C136 and L130-L132. The harmonic filter is a seven-pole elliptical low-pass configuration, optimized for low insertion loss, with a 3 dB frequency of approximately 180 MHz and typically less than 0.8 dB insertion loss in the passband. Antenna Matching Network The harmonic filter presents a 50Ω...
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THEORY OF OPERATION VHF Frequency Generation Circuitry The frequency generation system, shown in Figure 2-3, is composed of two circuit blocks, the Fractional-N synthesizer IC U201, the VCO/Buffer IC U251, and associated circuitry. Figure 2-4 shows the peripheral interconnect and support circuitry used in the synthesizer block, and Figure 2-5 details the internal circuitry of the VCOBIC and its interconnections to the surrounding components.
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VHF Frequency Generation Circuitry Fractional-N Synthesizer The Fractional-N synthesizer, shown in Figure 2-4, uses a 16.8 MHz crystal (Y201) to provide the reference frequency for the system. External components C201-C203, R202 and D201 are also part of the temperature-compensated oscillator circuit. The dc voltage applied to varactor D201 from U201 pin 25 is determined by a temperature-compensation algorithm within U201, and is specific to each crystal Y201, based on a unique code assigned to the crystal that identifies its temperature characteristics.
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THEORY OF OPERATION Voltage Controlled Oscillator (VCO) The VCOBIC (U251), shown in Figure 2-5, in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U251 pin 19) determines which oscillator and buffer are enabled. A sample of the RF signal from the enabled oscillator is routed from U251 pin 12 through a low pass filter, to the prescaler input of the synthesizer IC (U201 pin 32).
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Chapter 2 TROUBLESHOOTING TABLES This section contains detailed troubleshooting tables. These tables should be used as a guide in determining the problem areas. They are not a substitute for knowledge of circuit operation and astute troubleshooting techniques. It is advisable to refer to the related detailed circuit descriptions in the theory of operation sections prior to troubleshooting a radio.
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TROUBLESHOOTING TABLES Symptom Possible Causes Procedure Corrective Action No Audio 1. Synthesizer out of lock Verify U201-4 is at 3V dc. Troubleshoot synthesizer/VCO circuits. 2. Defective IFIC Verify audio is present at U51-8. Check Q70, Y70, U51. 3. RX audio buffer fault Verify audio is present at U451-2.
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Troubleshooting Table for Synthesizer Troubleshooting Table for Synthesizer Symptom Possible Causes Procedure Corrective Action Synthesizer Out of 1. VCO fault Verify oscillator is working, check RF Check VCO tank components Lock (RX mode level at U251-10 per schematic. connected to U251-5 and 6. only) Check dc voltages at U251 pin 2 Check for shorts/opens, replace...
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TROUBLESHOOTING TABLES Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action No Transmit (no 1. PTT switch defective. Verify U401-71 goes low when PTT Replace PTT switch S441. TX LED indication) is pressed. 2. EXT MIC PTT fault Verify U401-72 goes low when J471- Check/replace Q470, L471 etc.
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Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action Poor TX range, 1. RF test jack defective Verify continuity of J140 pins 3 and 4 Replace J140. conducted power in RX mode only. 2. Antenna matching net- Visually inspect components C140- Repair/replace if necessary.
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TROUBLESHOOTING TABLES Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) RF input 44.85 MHz 1.20 IFIC RF input decoupling 1.20 2nd LO osc output 4.02 2nd LO osc input 4.60 RSSI output 0.74 (no received signal) 4.70 Audio feedback...
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Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U110 RF input (TX mode) RF Power Amp Vgg (gate bias) 4.25V (typ) (TX mode) 6.59 (TX mode) RF output Do not measure Ground U150 Unit 1 output 5.8V (typ) (TX mode)
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TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U201 Ref osc XTAL2 Freq Synthesizer Ref osc warp output 3.00 Superfilter cap 4.48 Superfilter base (NU) 3.76 Superfilter output 4.52 Superfilter input 4.96 Prescaler input 1.97 Prescaler ground Prescaler Vdd 2.99 Prescaler Vref (NU) 1.97...
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Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U251 Prescaler output 2.26 VCO / Buffer TX switch output (NU) 0.06 Vcc_BUFFERS 3.00 TX VCO emitter (RX mode) TX VCO base (RX mode) GND_LOGIC Vcc_LOGIC 3.00 TRB input...
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Troubleshooting Table for Board and IC Signals 2-11 IC Designator Pin Function DC Voltage Comments (Condition) U401 PH1_PW2 3.00 Microprocessor PH0_PW1 3.23 Synth chip select XIRQ 3.00 1.48 RX enable 0.01 TX enable 3.23 Green LED enable Red LED enable 2.98 Lock detect from U201-4 MODB_VSTBY...
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2-12 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 PA3_IC4_OC5_OC1 3.00 Microprocessor PA4_OC4_OC1 Squelch detect input PA5_OC3_OC1 Channel activity input PA6_OC2_OC1 PA7_PA1_OC1 VSSR VDDR 3.23 ECLK (NU) 1.60 EXTAL 1.70 Clock from U451-28 XTAL 1.40 Not used VDDSYN XFC (NU) RESET...
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Troubleshooting Table for Board and IC Signals 2-13 IC Designator Pin Function DC Voltage Comments (Condition) U404 3.17 Flash ROM 0.30 0.22 3.03 3.08 3.06 0.24 3.08 3.05 3.05 0.69 0.94 1.08 0.78 0.59 0.66 0.67 0.75 EN_CE 3.01 From U401-38 0.16 EN_OE From U401-86...
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2-14 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U451 GCB1 general purpose output ASFIC_CMP GCB0 general purpose output 3.00 BW select (25 kHz mode) Squelch channel activity output To U401-84 Squelch detect digital output To U401-83 PL/low speed data I/O 1.50 High speed data I/O 3.00...
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Troubleshooting Table for Board and IC Signals 2-15 IC Designator Pin Function DC Voltage Comments (Condition) U480 Unit 1 output 2.48 Dual Opamp Unit 1 (-) input 2.48 Unit 1 (+) input 2.46 Ground Unit 2 (+) input 0.28 Unit 2 (-) input 0.29 Unit 2 output 4.96...
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Chapter 3 VHF1 PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards VHF1 (136-162MHz) The VHF circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This Chapter shows the schematics for the VHF circuits, the Controller circuits are contained in Section 2 of this manual.
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LAYER 6 (L6) SIDE 2 Speaker and Microphone Schematic MATES WITH J470 ON RADIO BOARD MATES WITH J491 ON RADIO BOARD 1.3.1 Speaker and Microphone Parts List Reference Motorola Part Description Designator 5080258E16 Microphone, electret 5005679X04 Speaker assembly with connector...
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Commercial Series CP040 Radios VHF2 (146-174MHz) Service Information Issue: May 2008...
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Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
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Table of Contents Chapter 1 THEORY OF OPERATION 1.0 Introduction ......................1-1 2.0 VHF2 (146-174MHz) Receiver................1-1 2.1 Receiver Front-End ..................1-2 2.2 Receiver Back-End..................1-3 3.0 VHF2 (146-174MHz) Transmitter.................1-4 3.1 Transmitter Power Amplifier ................1-4 3.2 Antenna Switch....................1-4 3.3 Harmonic Filter ....................1-5 3.4 Antenna Matching Network ................1-5 3.5 Power Control....................1-5 4.0 VHF2 (146-174MHz) Frequency Generation Circuitry.........1-6 4.1 Fractional-N Synthesizer ................1-7...
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Chapter 1 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the VHF circuits in the radio. Schematic diagrams and board layout diagrams are included in Chapter 4 in this Section of the manual. VHF2 (146-174MHz) Receiver The VHF receiver covers the range of 146-174 MHz and provides switchable IF bandwidth for use with 20/25/30 kHz or 12.5 kHz channel spacing systems.
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THEORY OF OPERATION Receiver Front End Incoming RF signals from the antenna are first routed through the harmonic filter and antenna switch, part of the transmitter circuitry, before being applied to the receiver front end. The receiver front end consists of a preselector filter, RF amplifier, an interstage filter, and a double-balanced first mixer.
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VHF2 (146-174MHz) Receiver Receiver Back End The receiver back end is a dual conversion design. High IF selectivity is provided by FL51, a 4-pole fundamental mode 44.85 MHz crystal filter with a minimum 3 dB bandwidth of + 6.7 kHz, a maximum 20 dB bandwidth of ±12.5 kHz, and a maximum insertion loss of 3.5 dB.
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THEORY OF OPERATION VHF2 Transmitter The VHF transmitter covers the range of 146-174 MHz. Depending on model, the output power of the transmitter is either switchable on a per-channel basis between high power (5 watts) and low power (1 watt), or is factory preset to 2 watts. The transmitter is divided into four major blocks as shown in Figure 2-2.
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VHF2 Transmitter Harmonic Filter The harmonic filter consists of components C130-C136 and L130-L132. The harmonic filter is a seven-pole elliptical low-pass configuration, optimized for low insertion loss, with a 3 dB frequency of approximately 210 MHz and typically less than 0.8 dB insertion loss in the passband. Antenna Matching Network The harmonic filter presents a 50Ω...
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THEORY OF OPERATION VHF2 Frequency Generation Circuitry The frequency generation system, shown in Figure 2-3, is composed of two circuit blocks, the Fractional-N synthesizer IC U201, the VCO/Buffer IC U251, and associated circuitry. Figure 2-4 shows the peripheral interconnect and support circuitry used in the synthesizer block, and Figure 2-5 details the internal circuitry of the VCOBIC and its interconnections to the surrounding components.
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VHF2 Frequency Generation Circuitry Fractional-N Synthesizer The Fractional-N synthesizer, shown in Figure 2-4, uses a 16.8 MHz crystal (Y201) to provide the reference frequency for the system. External components C201-C203, R202 and D201 are also part of the temperature-compensated oscillator circuit. The dc voltage applied to varactor D201 from U201 pin 25 is determined by a temperature-compensation algorithm within U201, and is specific to each crystal Y201, based on a unique code assigned to the crystal that identifies its temperature characteristics.
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THEORY OF OPERATION Voltage Controlled Oscillator (VCO) The VCOBIC (U251), shown in Figure 2-5, in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U251 pin 19) determines which oscillator and buffer are enabled. A sample of the RF signal from the enabled oscillator is routed from U251 pin 12 through a low pass filter, to the prescaler input of the synthesizer IC (U201 pin 32).
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Chapter 2 TROUBLESHOOTING TABLES This section contains detailed troubleshooting tables. These tables should be used as a guide in determining the problem areas. They are not a substitute for knowledge of circuit operation and astute troubleshooting techniques. It is advisable to refer to the related detailed circuit descriptions in the theory of operation sections prior to troubleshooting a radio.
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TROUBLESHOOTING TABLES Symptom Possible Causes Procedure Corrective Action No Audio 1. Synthesizer out of lock Verify U201-4 is at 3V dc. Troubleshoot synthesizer/VCO circuits. 2. Defective IFIC Verify audio is present at U51-8. Check Q70, Y70, U51. 3. RX audio buffer fault Verify audio is present at U451-2.
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Troubleshooting Table for Synthesizer Troubleshooting Table for Synthesizer Symptom Possible Causes Procedure Corrective Action Synthesizer Out of 1. VCO fault Verify oscillator is working, check RF Check VCO tank components Lock (RX mode level at U251-10 per schematic. connected to U251-5 and 6. only) Check dc voltages at U251 pin 2 Check for shorts/opens, replace...
Page 156
TROUBLESHOOTING TABLES Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action No Transmit (no 1. PTT switch defective. Verify U401-71 goes low when PTT Replace PTT switch S441. TX LED indication) is pressed. 2. EXT MIC PTT fault Verify U401-72 goes low when J471- Check/replace Q470, L471 etc.
Page 157
Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action Poor TX range, 1. RF test jack defective Verify continuity of J140 pins 3 and 4 Replace J140. conducted power in RX mode only. 2. Antenna matching net- Visually inspect components C140- Repair/replace if necessary.
Page 158
TROUBLESHOOTING TABLES Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) RF input 44.85 MHz 1.20 IFIC RF input decoupling 1.20 2nd LO osc output 4.02 2nd LO osc input 4.60 RSSI output 0.74 (no received signal) 4.70 Audio feedback...
Page 159
Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U110 RF input (TX mode) RF Power Amp Vgg (gate bias) 4.25V (typ) (TX mode) 6.59 (TX mode) RF output Do not measure Ground U150 Unit 1 output 5.8V (typ) (TX mode)
Page 160
TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U201 Ref osc XTAL2 Freq Synthesizer Ref osc warp output 3.00 Superfilter cap 4.48 Superfilter base (NU) 3.76 Superfilter output 4.52 Superfilter input 4.96 Prescaler input 1.97 Prescaler ground Prescaler Vdd 2.99 Prescaler Vref (NU) 1.97...
Page 161
Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U251 Prescaler output 2.26 VCO / Buffer TX switch output (NU) 0.06 Vcc_BUFFERS 3.00 TX VCO emitter (RX mode) TX VCO base (RX mode) GND_LOGIC Vcc_LOGIC 3.00 TRB input...
Page 163
Troubleshooting Table for Board and IC Signals 2-11 IC Designator Pin Function DC Voltage Comments (Condition) U401 PH1_PW2 3.00 Microprocessor PH0_PW1 3.23 Synth chip select XIRQ 3.00 1.48 RX enable 0.01 TX enable 3.23 Green LED enable Red LED enable 2.98 Lock detect from U201-4 MODB_VSTBY...
Page 164
2-12 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 PA3_IC4_OC5_OC1 3.00 Microprocessor PA4_OC4_OC1 Squelch detect input PA5_OC3_OC1 Channel activity input PA6_OC2_OC1 PA7_PA1_OC1 VSSR VDDR 3.23 ECLK (NU) 1.60 EXTAL 1.70 Clock from U451-28 XTAL 1.40 Not used VDDSYN XFC (NU) RESET...
Page 165
Troubleshooting Table for Board and IC Signals 2-13 IC Designator Pin Function DC Voltage Comments (Condition) U404 3.17 Flash ROM 0.30 0.22 3.03 3.08 3.06 0.24 3.08 3.05 3.05 0.69 0.94 1.08 0.78 0.59 0.66 0.67 0.75 EN_CE 3.01 From U401-38 0.16 EN_OE From U401-86...
Page 166
2-14 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U451 GCB1 general purpose output ASFIC_CMP GCB0 general purpose output 3.00 BW select (25 kHz mode) Squelch channel activity output To U401-84 Squelch detect digital output To U401-83 PL/low speed data I/O 1.50 High speed data I/O 3.00...
Page 167
Troubleshooting Table for Board and IC Signals 2-15 IC Designator Pin Function DC Voltage Comments (Condition) U480 Unit 1 output 2.48 Dual Opamp Unit 1 (-) input 2.48 Unit 1 (+) input 2.46 Ground Unit 2 (+) input 0.28 Unit 2 (-) input 0.29 Unit 2 output 4.96...
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Page 169
Chapter 3 VHF2 PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards VHF2 (146-174MHz) The VHF circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This Chapter shows the schematics for the VHF circuits, the Controller circuits are contained in Section 2 of this manual.
Page 170
VHF2 PCB/SCHEMATICS/PARTS LISTS Table 3-3 VHF2 Diagrams and Parts Lists PCB : 8486342Z09-A Main Board Top Side (EPP) Page 3-37 8486342Z09-A Main Board Bottom Side (EPP) Page 3-38 SCHEMATICS Radio Circuit Block Diagram Page 3-39 Receiver Front End Page 3-40 Receiver Back End Page 3-41 Synthesiser...
Page 171
LAYER 6 (L6) SIDE 2 Speaker and Microphone Schematic MATES WITH J470 ON RADIO BOARD MATES WITH J491 ON RADIO BOARD 1.3.1 Speaker and Microphone Parts List Reference Motorola Part Description Designator 5080258E16 Microphone, electret 5005679X04 Speaker assembly with connector...
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Page 208
3-40 VHF 146-174 MHz Schematic Diagrams, Overlays, and Parts Lists (8486342Z09-A) 5.0 V (RX) 0 V (TX) FE_5R 6.8K 3.95 V (RX) 1000pF UMT1 500 mV (RF) 3.95 V (RX) IF_OUT 560nH 3.38 V (RX) 100nH 1000pF 2.0 V (RX) 1000pF 0.1uF 6.8K...
Page 209
VHF 146-174 MHz Schematic Diagrams, Overlays, and Parts Lists (8486342Z09-A) 3-41 0 V (25 kHz) 5 V (12.5 kHz) 5 V (25 kHz) 0 V (12.5 kHz) U52-1 TC7W04F FL53 CFWC455E 0.1uF OUT 2 2.8 V (25 kHz) 1 V (25 kHz) 0 V (12.5 kHz) 0 V (12.5 kHz) U52-3...
Page 221
Commercial Series CP040 Radios UHF1 (403-440MHz) Service Information Issue: May 2008...
Page 222
Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
Page 223
Table of Contents Chapter 1 THEORY OF OPERATION 1.0 Introduction ......................1-1 2.0 UHF1 (403-440MHz) Receiver ................1-1 2.1 Receiver Front-End ..................1-2 2.2 Receiver Back-End..................1-3 3.0 UHF1 (403-440MHz) Transmitter.................1-4 3.1 Transmitter Power Amplifier ................1-4 3.2 Antenna Switch....................1-4 3.3 Harmonic Filter ....................1-5 3.4 Antenna Matching Network ................1-5 3.5 Power Control....................1-5 4.0 UHF1 (403-440MHz) Frequency Generation Circuitry........1-6 4.1 Fractional-N Synthesizer ................1-7...
Page 225
Chapter 1 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the UHF1 circuits in the radio. Schematic diagrams and board layout diagrams are included in Chapter 4 in this Section of the manual. UHF1 (403-440MHz) Receiver The UHF receiver covers the range of 403-440 MHz and provides switchable IF bandwidth for use with 20/25 kHz or 12.5 kHz channel spacing systems.
Page 226
THEORY OF OPERATION Receiver Front End Incoming RF signals from the antenna are first routed through the harmonic filter and antenna switch, part of the transmitter circuitry, before being applied to the receiver front end. The receiver front end consists of a preselector filter, RF amplifier, an interstage filter, and a double-balanced first mixer.
Page 227
UHF1 (403-440MHz) Receiver Receiver Back End The receiver back end is a dual conversion design. High IF selectivity is provided by FL51, a 4-pole fundamental mode 44.85 MHz crystal filter with a minimum 3 dB bandwidth of ±6.7 kHz, a maximum 20 dB bandwidth of + 12.5 kHz, and a maximum insertion loss of 3.5 dB.
Page 228
THEORY OF OPERATION UHF1 Transmitter The UHF transmitter covers the range of 403-440 MHz. Depending on model, the output power of the transmitter is either switchable on a per-channel basis between high power (4 watts) and low power (1 watt), or is factory preset to 2 watts. The transmitter is divided into four major blocks as shown in Figure 2-2.
Page 229
UHF1 Transmitter Harmonic Filter The harmonic filter consists of components C122 and L130-L132. The harmonic filter is a seven- pole Chebychev low-pass configuration, optimized for low insertion loss, with a 3 dB frequency of approximately 600 MHz and typically less than 0.8 dB insertion loss in the passband. Antenna Matching Network The harmonic filter presents a 50Ω...
Page 230
THEORY OF OPERATION UHF1 Frequency Generation Circuitry The frequency generation system, shown in Figure 2-3, is composed of two circuit blocks, the Fractional-N synthesizer IC U201, the VCO/Buffer IC U251, and associated circuitry. Figure 2-4 shows the peripheral interconnect and support circuitry used in the synthesizer block, and Figure 2-5 details the internal circuitry of the VCOBIC and its interconnections to the surrounding components.
Page 231
UHF1 Frequency Generation Circuitry Fractional-N Synthesizer The Fractional-N synthesizer, shown in Figure 2-4, uses a 16.8 MHz crystal (Y201) to provide the reference frequency for the system. External components C201-C203, R202 and D201 are also part of the temperature-compensated oscillator circuit. The dc voltage applied to varactor D201 from U201 pin 25 is determined by a temperature-compensation algorithm within U201, and is specific to each crystal Y201, based on a unique code assigned to the crystal that identifies its temperature characteristics.
Page 232
THEORY OF OPERATION Voltage Controlled Oscillator (VCO) The VCOBIC (U251), shown in Figure 2-5, in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U251 pin 19) determines which oscillator and buffer are enabled. A sample of the RF signal from the enabled oscillator is routed from U251 pin 12 through a low pass filter, to the prescaler input of the synthesizer IC (U201 pin 32).
Page 233
Chapter 2 TROUBLESHOOTING TABLES This section contains detailed troubleshooting tables. These tables should be used as a guide in determining the problem areas. They are not a substitute for knowledge of circuit operation and astute troubleshooting techniques. It is advisable to refer to the related detailed circuit descriptions in the theory of operation sections prior to troubleshooting a radio.
Page 234
TROUBLESHOOTING TABLES Symptom Possible Causes Procedure Corrective Action No Audio 1. Synthesizer out of lock Verify U201-4 is at 3V dc. Troubleshoot synthesizer/VCO circuits. 2. Defective IFIC Verify audio is present at U51-8. Check Q70, Y70, U51. 3. RX audio buffer fault Verify audio is present at U451-2.
Page 235
Troubleshooting Table for Synthesizer Troubleshooting Table for Synthesizer Symptom Possible Causes Procedure Corrective Action Synthesizer Out of 1. VCO fault Verify oscillator is working, check RF Check VCO tank components Lock (RX mode level at U251-10 per schematic. connected to U251-5 and 6. only) Check dc voltages at U251 pin 2 Check for shorts/opens, replace...
Page 236
TROUBLESHOOTING TABLES Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action No Transmit (no 1. PTT switch defective. Verify U401-71 goes low when PTT Replace PTT switch S441. TX LED indication) is pressed. 2. EXT MIC PTT fault Verify U401-72 goes low when J471- Check/replace Q470, L471 etc.
Page 237
Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action Poor TX range, 1. RF test jack defective Verify continuity of J140 pins 3 and 4 Replace J140. conducted power in RX mode only. 2. Antenna matching net- Visually inspect components C140- Repair/replace if necessary.
Page 238
TROUBLESHOOTING TABLES Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) RF input 44.85 MHz 1.20 IFIC RF input decoupling 1.20 2nd LO osc output 4.02 2nd LO osc input 4.60 RSSI output 0.74 (no received signal) 4.70 Audio feedback...
Page 239
Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U110 RF input (TX mode) RF Power Amp Vgg (gate bias) 2.65 (typ) (TX mode) 6.59 (TX mode) RF output Do not measure Ground U150 Unit 1 output 4.20 (typ) (TX mode)
Page 240
TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U201 Ref osc XTAL2 Freq Synthesizer Ref osc warp output 3.00 Superfilter cap 4.48 Superfilter base (NU) 3.76 Superfilter output 4.52 Superfilter input 4.96 Prescaler input 1.97 Prescaler ground Prescaler Vdd 2.99 Prescaler Vref (NU) 1.97...
Page 241
Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U251 Prescaler output 2.26 VCO / Buffer TX switch output (NU) 0.06 Vcc_BUFFERS 3.00 TX VCO emitter (RX mode) TX VCO base (RX mode) GND_LOGIC Vcc_LOGIC 3.00 TRB input...
Page 243
Troubleshooting Table for Board and IC Signals 2-11 IC Designator Pin Function DC Voltage Comments (Condition) U401 PH1_PW2 3.00 Microprocessor PH0_PW1 3.23 Synth chip select XIRQ 3.00 1.48 RX enable 0.01 TX enable 3.23 Green LED enable Red LED enable 2.98 Lock detect from U201-4 MODB_VSTBY...
Page 244
2-12 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 PA3_IC4_OC5_OC1 3.00 Microprocessor PA4_OC4_OC1 Squelch detect input PA5_OC3_OC1 Channel activity input PA6_OC2_OC1 PA7_PA1_OC1 VSSR VDDR 3.23 ECLK (NU) 1.60 EXTAL 1.70 Clock from U451-28 XTAL 1.40 Not used VDDSYN XFC (NU) RESET...
Page 245
Troubleshooting Table for Board and IC Signals 2-13 IC Designator Pin Function DC Voltage Comments (Condition) U404 3.17 Flash ROM 0.30 0.22 3.03 3.08 3.06 0.24 3.08 3.05 3.05 0.69 0.94 1.08 0.78 0.59 0.66 0.67 0.75 EN_CE 3.01 From U401-38 0.16 EN_OE From U401-86...
Page 246
2-14 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U451 GCB1 general purpose output ASFIC_CMP GCB0 general purpose output 3.00 BW select (25 kHz mode) Squelch channel activity output To U401-84 Squelch detect digital output To U401-83 PL/low speed data I/O 1.50 High speed data I/O 3.00...
Page 247
Troubleshooting Table for Board and IC Signals 2-15 IC Designator Pin Function DC Voltage Comments (Condition) U480 Unit 1 output 2.48 Dual Opamp Unit 1 (-) input 2.48 Unit 1 (+) input 2.46 Ground Unit 2 (+) input 0.28 Unit 2 (-) input 0.29 Unit 2 output 4.96...
Page 248
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Page 249
Chapter 3 UHF1 PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards UHF1 (403-440MHz) The UHF1 circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This Chapter shows the schematics for the UHF circuits, the Controller circuits are contained in Section 2 of this manual.
Page 250
LAYER 6 (L6) SIDE 2 Speaker and Microphone Schematic MATES WITH J470 ON RADIO BOARD MATES WITH J491 ON RADIO BOARD 1.3.1 Speaker and Microphone Parts List Reference Motorola Part Description Designator 5080258E16 Microphone, electret 5005679X04 Speaker assembly with connector...
Page 270
UHF1 PCB 8416205H02-C/-D Schematic Diagrams 3-22 0 V (Tx) FE_5R 5.6K 390pF 4.2 V (Rx) UMT1 3.66 V (Rx) 4.2 V (Rx) 390pF 390pF 22nH 4.2 V (Rx) 0.1uF C523 363 mV (RF) 0.45pF 5.6K C521 4.2 V (Rx) 6.7% 5.1pF 1.5K -7.5 dBm...
Page 271
UHF1 PCB 8416205H02-C/-D Schematic Diagrams 3-23 0 V for 25 kHz 5 V (25 kHz) 5 V for 12.5 kHz 0 V (12.5 kHz) U52-1 TC7W04F FL53 CFWC455E 0.1uF OUT 2 2.8 V (25 kHz) 1 V (25 kHz) 0 V (12.5 kHz) 0 V (12.5 kHz) U52-3 TC7W04F...
Page 279
UHF1 PCB 8416205H02-C/-D (EPP) Parts List 3-31 UHF1 PCB 8416205H02-C/-D Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description (EPP) Parts List Part No. Part No. Part No. Circuit Motorola 2113944A38 CAP,82.0PF 50V C114 2113945A04 CAP, 390PF 50V C214 2113945A09...
Page 280
UHF1 PCB 8416205H02-C/-D (EPP) Parts List 3-32 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C281 2113945A04 CAP, 390PF 50V C414 2113946K02 CAP, 0.10UF 16V C474 2113944A42 CAP,150.0PF 50V...
Page 281
UHF1 PCB 8416205H02-C/-D (EPP) Parts List 3-33 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. 2414017N26 IND, 150.0 NH Q171 4813973A42 XSTR,BIP GP SS,NPN 0613952Q75 RES 1200 OHM...
Page 282
LABEL BARCODE R420 0613952P30 RES 200K OHM R491 0613952R66 RES 0.0 OHM SH201 2686423Z02 SHIELD, 19 X 19 X 3.03 MM * Motorola Depot Servicing only R421 0613952P01 RES, 100K OHM R492 0613952R10 RES 24K OHM SH250 2686425Z02 SHIELD R422...
Page 283
Commercial Series CP040 Radios UHF2 (438-470MHz) Service Information Issue: May 2008...
Page 284
Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
Page 285
Table of Contents Chapter 1 THEORY OF OPERATION 1.0 Introduction ......................1-1 2.0 UHF2 (438-470MHz) Receiver ................1-1 2.1 Receiver Front-End ..................1-2 2.2 Receiver Back-End..................1-3 3.0 UHF2 (438-470MHz) Transmitter.................1-4 3.1 Transmitter Power Amplifier ................1-4 3.2 Antenna Switch....................1-4 3.3 Harmonic Filter ....................1-5 3.4 Antenna Matching Network ................1-5 3.5 Power Control....................1-5 4.0 UHF2 (438-470MHz) Frequency Generation Circuitry........1-6 4.1 Fractional-N Synthesizer ................1-7...
Page 287
Chapter 1 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the UHF circuits in the radio. Schematic diagrams and board layout diagrams are included in Chapter 4 in this Section of the manual. UHF (438-470MHz) Receiver The UHF receiver covers the range of 438-470 MHz and provides switchable IF bandwidth for use with 20/25 kHz or 12.5 kHz channel spacing systems.
Page 288
THEORY OF OPERATION Receiver Front End Incoming RF signals from the antenna are first routed through the harmonic filter and antenna switch, part of the transmitter circuitry, before being applied to the receiver front end. The receiver front end consists of a preselector filter, RF amplifier, an interstage filter, and a double-balanced first mixer.
Page 289
UHF (438-470MHz) Receiver Receiver Back End The receiver back end is a dual conversion design. High IF selectivity is provided by FL51, a 4-pole fundamental mode 44.85 MHz crystal filter with a minimum 3 dB bandwidth of ±6.7 kHz, a maximum 20 dB bandwidth of + 12.5 kHz, and a maximum insertion loss of 3.5 dB.
Page 290
THEORY OF OPERATION UHF2 Transmitter The UHF transmitter covers the range of 438-470 MHz. Depending on model, the output power of the transmitter is either switchable on a per-channel basis between high power (4 watts) and low power (1 watt), or is factory preset to 2 watts. The transmitter is divided into four major blocks as shown in Figure 2-2.
Page 291
UHF2 Transmitter Harmonic Filter The harmonic filter consists of components C130-C136 and L130-L132. The harmonic filter is a seven-pole Chebychev low-pass configuration, optimized for low insertion loss, with a 3 dB frequency of approximately 600 MHz and typically less than 0.8 dB insertion loss in the passband. Antenna Matching Network The harmonic filter presents a 50Ω...
Page 292
THEORY OF OPERATION UHF2 Frequency Generation Circuitry The frequency generation system, shown in Figure 2-3, is composed of two circuit blocks, the Fractional-N synthesizer IC U201, the VCO/Buffer IC U251, and associated circuitry. Figure 2-4 shows the peripheral interconnect and support circuitry used in the synthesizer block, and Figure 2-5 details the internal circuitry of the VCOBIC and its interconnections to the surrounding components.
Page 293
UHF2 Frequency Generation Circuitry Fractional-N Synthesizer The Fractional-N synthesizer, shown in Figure 2-4, uses a 16.8 MHz crystal (Y201) to provide the reference frequency for the system. External components C201-C203, R202 and D201 are also part of the temperature-compensated oscillator circuit. The dc voltage applied to varactor D201 from U201 pin 25 is determined by a temperature-compensation algorithm within U201, and is specific to each crystal Y201, based on a unique code assigned to the crystal that identifies its temperature characteristics.
Page 294
THEORY OF OPERATION Voltage Controlled Oscillator (VCO) The VCOBIC (U251), shown in Figure 2-5, in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U251 pin 19) determines which oscillator and buffer are enabled. A sample of the RF signal from the enabled oscillator is routed from U251 pin 12 through a low pass filter, to the prescaler input of the synthesizer IC (U201 pin 32).
Page 295
Chapter 2 TROUBLESHOOTING TABLES This section contains detailed troubleshooting tables. These tables should be used as a guide in determining the problem areas. They are not a substitute for knowledge of circuit operation and astute troubleshooting techniques. It is advisable to refer to the related detailed circuit descriptions in the theory of operation sections prior to troubleshooting a radio.
Page 296
TROUBLESHOOTING TABLES Symptom Possible Causes Procedure Corrective Action No Audio 1. Synthesizer out of lock Verify U201-4 is at 3V dc. Troubleshoot synthesizer/VCO circuits. 2. Defective IFIC Verify audio is present at U51-8. Check Q70, Y70, U51. 3. RX audio buffer fault Verify audio is present at U451-2.
Page 297
Troubleshooting Table for Synthesizer Troubleshooting Table for Synthesizer Symptom Possible Causes Procedure Corrective Action Synthesizer Out of 1. VCO fault Verify oscillator is working, check RF Check VCO tank components Lock (RX mode level at U251-10 per schematic. connected to U251-5 and 6. only) Check dc voltages at U251 pin 2 Check for shorts/opens, replace...
Page 298
TROUBLESHOOTING TABLES Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action No Transmit (no 1. PTT switch defective. Verify U401-71 goes low when PTT Replace PTT switch S441. TX LED indication) is pressed. 2. EXT MIC PTT fault Verify U401-72 goes low when J471- Check/replace Q470, L471 etc.
Page 299
Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action Poor TX range, 1. RF test jack defective Verify continuity of J140 pins 3 and 4 Replace J140. conducted power in RX mode only. 2. Antenna matching net- Visually inspect components C140- Repair/replace if necessary.
Page 300
TROUBLESHOOTING TABLES Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) RF input 44.85 MHz 1.20 IFIC RF input decoupling 1.20 2nd LO osc output 4.02 2nd LO osc input 4.60 RSSI output 0.74 (no received signal) 4.70 Audio feedback...
Page 301
Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U110 RF input (TX mode) RF Power Amp Vgg (gate bias) 2.65 (typ) (TX mode) 6.59 (TX mode) RF output Do not measure Ground U150 Unit 1 output 4.20 (typ) (TX mode)
Page 302
TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U201 Ref osc XTAL2 Freq Synthesizer Ref osc warp output 3.00 Superfilter cap 4.48 Superfilter base (NU) 3.76 Superfilter output 4.52 Superfilter input 4.96 Prescaler input 1.97 Prescaler ground Prescaler Vdd 2.99 Prescaler Vref (NU) 1.97...
Page 303
Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U251 Prescaler output 2.26 VCO / Buffer TX switch output (NU) 0.06 Vcc_BUFFERS 3.00 TX VCO emitter (RX mode) TX VCO base (RX mode) GND_LOGIC Vcc_LOGIC 3.00 TRB input...
Page 305
Troubleshooting Table for Board and IC Signals 2-11 IC Designator Pin Function DC Voltage Comments (Condition) U401 PH1_PW2 3.00 Microprocessor PH0_PW1 3.23 Synth chip select XIRQ 3.00 1.48 RX enable 0.01 TX enable 3.23 Green LED enable Red LED enable 2.98 Lock detect from U201-4 MODB_VSTBY...
Page 306
2-12 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 PA3_IC4_OC5_OC1 3.00 Microprocessor PA4_OC4_OC1 Squelch detect input PA5_OC3_OC1 Channel activity input PA6_OC2_OC1 PA7_PA1_OC1 VSSR VDDR 3.23 ECLK (NU) 1.60 EXTAL 1.70 Clock from U451-28 XTAL 1.40 Not used VDDSYN XFC (NU) RESET...
Page 307
Troubleshooting Table for Board and IC Signals 2-13 IC Designator Pin Function DC Voltage Comments (Condition) U404 3.17 Flash ROM 0.30 0.22 3.03 3.08 3.06 0.24 3.08 3.05 3.05 0.69 0.94 1.08 0.78 0.59 0.66 0.67 0.75 EN_CE 3.01 From U401-38 0.16 EN_OE From U401-86...
Page 308
2-14 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U451 GCB1 general purpose output ASFIC_CMP GCB0 general purpose output 3.00 BW select (25 kHz mode) Squelch channel activity output To U401-84 Squelch detect digital output To U401-83 PL/low speed data I/O 1.50 High speed data I/O 3.00...
Page 309
Troubleshooting Table for Board and IC Signals 2-15 IC Designator Pin Function DC Voltage Comments (Condition) U480 Unit 1 output 2.48 Dual Opamp Unit 1 (-) input 2.48 Unit 1 (+) input 2.46 Ground Unit 2 (+) input 0.28 Unit 2 (-) input 0.29 Unit 2 output 4.96...
Page 311
Chapter 3 UHF2 PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards UHF2 (438-470MHz) The UHF circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This Chapter shows the schematics for the UHF circuits, the Controller circuits are contained in Section 2 of this manual.
Page 312
UHF2 PCB/SCHEMATICS/PARTS LISTS Table 3-3 UHF2 Diagrams and Parts Lists PCB : 8486348Z09-A Main Board Top Side Page 3-37 8486348Z09-A Main Board Bottom Side Page 3-38 SCHEMATICS Radio Circuit Block Diagram Page 3-39 Receiver Front End Page 3-40 Receiver Back End Page 3-41 Synthesiser Page 3-42...
Page 313
LAYER 6 (L6) SIDE 2 Speaker and Microphone Schematic MATES WITH J470 ON RADIO BOARD MATES WITH J491 ON RADIO BOARD 1.3.1 Speaker and Microphone Parts List Reference Motorola Part Description Designator 5080258E16 Microphone, electret 5005679X04 Speaker assembly with connector...
Page 314
UHF2 PCB/SCHEMATICS/PARTS LISTS THIS PAGE INTENTIONALLY LEFT BLANK...
Page 334
UHF2 PCB 8416205H02-C/-D Schematic Diagrams 3-24 0 V (Tx) FE_5R 5.6K 390pF 4.2 V (Rx) UMT1 3.66 V (Rx) 4.2 V (Rx) 390pF 390pF 22nH 4.2 V (Rx) 0.1uF C523 363 mV (RF) 0.45pF 5.6K C521 4.2 V (Rx) 6.7% 5.1pF 1.5K -7.5 dBm...
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UHF2 PCB 8416205H02-C/-D Schematic Diagrams 3-25 0 V for 25 kHz 5 V (25 kHz) 5 V for 12.5 kHz 0 V (12.5 kHz) U52-1 TC7W04F FL53 0.1uF CFWC455E OUT 2 2.8 V (25 kHz) 1 V (25 kHz) 0 V (12.5 kHz) 0 V (12.5 kHz) U52-3 TC7W04F...
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3-40 UHF (438-470 MHz) Schematic Diagrams, Overlays, and Parts Lists (8486348Z09-A) 5 V (RX) 0 V (TX) FE_5R 5.6K 4.2 V (RX) 390pF UMT1 3.66 V (RX) 4.2 V (RX) 390pF 390pF 18nH 1.93 V (RX) 0.1uF +7.5 dBm C523 363 mV (RF) 0.2pF 5.6K...
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UHF (438-470 MHz) Schematic Diagrams, Overlays, and Parts Lists (8486348Z09-A) 3-41 0 V (25 kHz) 5 V (12.5 kHz) 5 V (25 kHz) 0 V (12.5 kHz) U52-1 TC7W04F FL53 CFWC455E 0.1uF 1 IN 2.8 V (25 kHz) 1 V (25 kHz) 0 V (12.5 kHz) 0 V (12.5 kHz) U52-3...
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Commercial Series CP040 Radios UHF3 (465-495MHz) Service Information Issue: May 2008...
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Accordingly, any copyrighted Motorola computer programs contained in the Motorola products described in this manual may not be copied or reproduced in any manner without the express written permission of Motorola. Furthermore, the purchase of Motorola...
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Table of Contents Chapter 1 THEORY OF OPERATION 1.0 Introduction ......................1-1 2.0 UHF3 (465-495MHz) Receiver ................1-1 2.1 Receiver Front-End ..................1-2 2.2 Receiver Back-End..................1-3 3.0 UHF3 (465-495MHz) Transmitter.................1-4 3.1 Transmitter Power Amplifier ................1-4 3.2 Antenna Switch....................1-4 3.3 Harmonic Filter ....................1-5 3.4 Antenna Matching Network ................1-5 3.5 Power Control....................1-5 4.0 UHF3 (465-495MHz) Frequency Generation Circuitry........1-6 4.1 Fractional-N Synthesizer ................1-7...
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Chapter 1 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the UHF circuits in the radio. Schematic diagrams and board layout diagrams are included in Chapter 4 in this Section of the manual. UHF3 (465-495MHz) Receiver The UHF receiver covers the range of 465-495 MHz and provides switchable IF bandwidth for use with 20/25 kHz or 12.5 kHz channel spacing systems.
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THEORY OF OPERATION Receiver Front End Incoming RF signals from the antenna are first routed through the harmonic filter and antenna switch, part of the transmitter circuitry, before being applied to the receiver front end. The receiver front end consists of a preselector filter, RF amplifier, an interstage filter, and a double-balanced first mixer.
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UHF3 (465-495MHz) Receiver Receiver Back End The receiver back end is a dual conversion design. High IF selectivity is provided by FL51, a 4-pole fundamental mode 44.85 MHz crystal filter with a minimum 3 dB bandwidth of ±6.7 kHz, a maximum 20 dB bandwidth of + 12.5 kHz, and a maximum insertion loss of 3.5 dB.
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THEORY OF OPERATION UHF3 Transmitter The UHF transmitter covers the range of 465-495 MHz. Depending on model, the output power of the transmitter is either switchable on a per-channel basis between high power (4 watts) and low power (1 watt), or is factory preset to 2 watts. The transmitter is divided into four major blocks as shown in Figure 2-2.
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UHF3 Transmitter Harmonic Filter The harmonic filter consists of components C130-C136 and L130-L132. The harmonic filter is a seven-pole Chebychev low-pass configuration, optimized for low insertion loss, with a 3 dB frequency of approximately 600 MHz and typically less than 0.8 dB insertion loss in the passband. Antenna Matching Network The harmonic filter presents a 50Ω...
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THEORY OF OPERATION UHF3 Frequency Generation Circuitry The frequency generation system, shown in Figure 2-3, is composed of two circuit blocks, the Fractional-N synthesizer IC U201, the VCO/Buffer IC U251, and associated circuitry. Figure 2-4 shows the peripheral interconnect and support circuitry used in the synthesizer block, and Figure 2-5 details the internal circuitry of the VCOBIC and its interconnections to the surrounding components.
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UHF3 Frequency Generation Circuitry Fractional-N Synthesizer The Fractional-N synthesizer, shown in Figure 2-4, uses a 16.8 MHz crystal (Y201) to provide the reference frequency for the system. External components C201-C203, R202 and D201 are also part of the temperature-compensated oscillator circuit. The dc voltage applied to varactor D201 from U201 pin 25 is determined by a temperature-compensation algorithm within U201, and is specific to each crystal Y201, based on a unique code assigned to the crystal that identifies its temperature characteristics.
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THEORY OF OPERATION Voltage Controlled Oscillator (VCO) The VCOBIC (U251), shown in Figure 2-5, in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U251 pin 19) determines which oscillator and buffer are enabled. A sample of the RF signal from the enabled oscillator is routed from U251 pin 12 through a low pass filter, to the prescaler input of the synthesizer IC (U201 pin 32).
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Chapter 2 TROUBLESHOOTING TABLES This section contains detailed troubleshooting tables. These tables should be used as a guide in determining the problem areas. They are not a substitute for knowledge of circuit operation and astute troubleshooting techniques. It is advisable to refer to the related detailed circuit descriptions in the theory of operation sections prior to troubleshooting a radio.
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TROUBLESHOOTING TABLES Symptom Possible Causes Procedure Corrective Action No Audio 1. Synthesizer out of lock Verify U201-4 is at 3V dc. Troubleshoot synthesizer/VCO circuits. 2. Defective IFIC Verify audio is present at U51-8. Check Q70, Y70, U51. 3. RX audio buffer fault Verify audio is present at U451-2.
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Troubleshooting Table for Synthesizer Troubleshooting Table for Synthesizer Symptom Possible Causes Procedure Corrective Action Synthesizer Out of 1. VCO fault Verify oscillator is working, check RF Check VCO tank components Lock (RX mode level at U251-10 per schematic. connected to U251-5 and 6. only) Check dc voltages at U251 pin 2 Check for shorts/opens, replace...
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TROUBLESHOOTING TABLES Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action No Transmit (no 1. PTT switch defective. Verify U401-71 goes low when PTT Replace PTT switch S441. TX LED indication) is pressed. 2. EXT MIC PTT fault Verify U401-72 goes low when J471- Check/replace Q470, L471 etc.
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Troubleshooting Table for Transmitter Symptom Possible Causes Procedure Corrective Action Poor TX range, 1. RF test jack defective Verify continuity of J140 pins 3 and 4 Replace J140. conducted power in RX mode only. 2. Antenna matching net- Visually inspect components C140- Repair/replace if necessary.
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TROUBLESHOOTING TABLES Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) RF input 44.85 MHz 1.20 IFIC RF input decoupling 1.20 2nd LO osc output 4.02 2nd LO osc input 4.60 RSSI output 0.74 (no received signal) 4.70 Audio feedback...
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Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U110 RF input (TX mode) RF Power Amp Vgg (gate bias) 2.65 (typ) (TX mode) 6.59 (TX mode) RF output Do not measure Ground U150 Unit 1 output 4.20 (typ) (TX mode)
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TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U201 Ref osc XTAL2 Freq Synthesizer Ref osc warp output 3.00 Superfilter cap 4.48 Superfilter base (NU) 3.76 Superfilter output 4.52 Superfilter input 4.96 Prescaler input 1.97 Prescaler ground Prescaler Vdd 2.99 Prescaler Vref (NU) 1.97...
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Troubleshooting Table for Board and IC Signals IC Designator Pin Function DC Voltage Comments (Condition) U251 Prescaler output 2.26 VCO / Buffer TX switch output (NU) 0.06 Vcc_BUFFERS 3.00 TX VCO emitter (RX mode) TX VCO base (RX mode) GND_LOGIC Vcc_LOGIC 3.00 TRB input...
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Troubleshooting Table for Board and IC Signals 2-11 IC Designator Pin Function DC Voltage Comments (Condition) U401 PH1_PW2 3.00 Microprocessor PH0_PW1 3.23 Synth chip select XIRQ 3.00 1.48 RX enable 0.01 TX enable 3.23 Green LED enable Red LED enable 2.98 Lock detect from U201-4 MODB_VSTBY...
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2-12 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U401 PA3_IC4_OC5_OC1 3.00 Microprocessor PA4_OC4_OC1 Squelch detect input PA5_OC3_OC1 Channel activity input PA6_OC2_OC1 PA7_PA1_OC1 VSSR VDDR 3.23 ECLK (NU) 1.60 EXTAL 1.70 Clock from U451-28 XTAL 1.40 Not used VDDSYN XFC (NU) RESET...
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Troubleshooting Table for Board and IC Signals 2-13 IC Designator Pin Function DC Voltage Comments (Condition) U404 3.17 Flash ROM 0.30 0.22 3.03 3.08 3.06 0.24 3.08 3.05 3.05 0.69 0.94 1.08 0.78 0.59 0.66 0.67 0.75 EN_CE 3.01 From U401-38 0.16 EN_OE From U401-86...
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2-14 TROUBLESHOOTING TABLES IC Designator Pin Function DC Voltage Comments (Condition) U451 GCB1 general purpose output ASFIC_CMP GCB0 general purpose output 3.00 BW select (25 kHz mode) Squelch channel activity output To U401-84 Squelch detect digital output To U401-83 PL/low speed data I/O 1.50 High speed data I/O 3.00...
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Troubleshooting Table for Board and IC Signals 2-15 IC Designator Pin Function DC Voltage Comments (Condition) U480 Unit 1 output 2.48 Dual Opamp Unit 1 (-) input 2.48 Unit 1 (+) input 2.46 Ground Unit 2 (+) input 0.28 Unit 2 (-) input 0.29 Unit 2 output 4.96...
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Chapter 3 UHF3 PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards UHF3 (465-495MHz) The UHF circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This Chapter shows the schematics for the UHF circuits, the Controller circuits are contained in Section 2 of this manual.
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UHF3 PCB/SCHEMATICS/PARTS LISTS PCB : 8486768Z02-A Main Board Top Side Page 3-37 8486768Z02-A Main Board Bottom Side Page 3-38 SCHEMATICS Radio Circuit Block Diagram Page 3-39 Receiver Front End Page 3-40 Receiver Back End Page 3-41 Synthesiser Page 3-42 Page 3-43 Transmit and Power Control Cct Page 3-44 Controller Interconnect Schematic Diagram...
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LAYER 6 (L6) SIDE 2 Speaker and Microphone Schematic MATES WITH J470 ON RADIO BOARD MATES WITH J491 ON RADIO BOARD 1.3.1 Speaker and Microphone Parts List Reference Motorola Part Description Designator 5080258E16 Microphone, electret 5005679X04 Speaker assembly with connector...
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UHF3 PCB/SCHEMATICS/PARTS LISTS THIS PAGE INTENTIONALLY LEFT BLANK...