Summary of Contents for Motorola Professional GP340
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Professional Radio GP Series Detailed Service Manual 6866558D04-O...
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Professional Radio GP Series Detailed Service Manual 6866558D04-O Contents Section 1 Service Maintainability Section 2 Keypad Service Information Section 3 Power Distribution and Controller Information Section 4 VHF Service Information Section 5 300R1 Service Information Section 6 Lowband Service Information KTT EMEA Publications Department, Jays Close, Viables Industrial Estate, Basingstoke, Hampshire, RG22 4PD, UK.
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.
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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Motorola - approved antennas, batteries and accessories may exceed IEEE/ICNIRP RF exposure 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.
viii 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.
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.
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.
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Professional Radio GP Series 300R1 (300 - 350MHz) Service Information Issue: November 2004...
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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...
Chapter 1 MODEL CHART AND TECHNICAL SPECIFICATIONS GP340 Model Chart Professional GP300 Series (300-350MHz) Model Description MDH25EDC9AN3_E GP340 300R1 300-350 MHz 4W 16 CH Item Description PMLD4141_ GP340 Back Cover Kit 6864110B13_ GP340 Basic User Guide PMAD4022_ 9cm (300-344 MHz) Antenna HNN9008_ Battery, NiMH Standard x = Indicates one of each is required.
MODEL CHART AND TECHNICAL SPECIFICATIONS Technical Specifications Data is specified for +25°C unless otherwise stated. General Specifications Channel Capacity GP340 GP640 16 (Conventional) GP680 16 (Conventional) Power Supply Rechargeable battery 7.5v Dimensions: H x W x D (mm) Height excluding knobs With standard high capacity NiMH battery 137 x 57.5 x 37.5 With ultra high capacity NiMH battery...
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Technical Specifications Transmitter 300R1 *Frequencies - Full Bandsplit 300-350 MHz Channel Spacing 12.5/20/25 kHz Frequency Stability ±2.5 ppm @ 12.5kHz (-25°C to +55°C, +25° Ref.) ±5ppm @ 25 kHz Power 1-4W ±2.5 @ 12.5 kHz Modulation Limiting ±4.0 @ 20 kHz ±5.0 @ 25 kHz FM Hum &...
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MODEL CHART AND TECHNICAL SPECIFICATIONS...
Chapter 2 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the 300-350MHz circuits in the radio. For details of the theory of operation and trouble shooting for the the associated Controller circuits refer to the Controller Section of this manual. Transmitter (Refer to Figure 2-1 and the Transmitter schematic diagram) The transmitter contains five basic circuits:...
THEORY OF OPERATION The PRF1507 LDMOS PA is capable of supplying an output power of 7W with an input signal of 0.3W. The current drain would typically be 1300mA while operating in the frequency range of 300-350MHz. The power output can be varied by changing the biasing voltage. Antenna Switch The antenna switch circuit consists of two PIN diodes (CR101 and CR102), a pi network (C107, L104 and C106), and two current limiting resistors (R101, R170).
Receiver Receiver Antenna Pin Diode Varactor Varactor Antenna Crystal RF Amp Mixer IF Amp Tuned Filter Tuned Filter Switch RF Jack Filter First LO from FGU Control Voltage from ASFIC Recovered Audio Demodulator Squelch U301 RSSI Synthesizer 16.8 MHz Reference Clock SPI Bus Second LO VCO...
THEORY OF OPERATION Both the pre and post-RF amplifier varactor tuned filters have similar responses. The 3dB bandwidth of the filter is about 50 MHz. This enables the filters to be electronically controlled by using a single control voltage which is DACRx . The output of the post-RF amplifier filter which is connected to the passive double balanced mixer consists of T301, T302 and CR306.
Receiver Automatic Gain Control Circuit (Refer to the Receiver Front End and Receiver Back End schematic diagrams) The front end automatic gain control circuit is to provide automatic gain reduction of the front end RF amplifier via feedback. This action is necessary to prevent overloading of backend circuits. This is achieved by drawing some of the output power from the RF amplifier’s output.
THEORY OF OPERATION Frequency Generation Circuitry (Refer to Figure 2-3 and the Frequency Synthesizer schematic diagram) The Frequency Generation Circuitry is composed of two main ICs, the Fractional-N synthesizer (U201), and the VCO/Buffer IC (U241). Designed in conjunction to maximize compatibility, the two ICs provide many of the functions that normally would require additional circuitry.
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Frequency Generation Circuitry In achieving fast locking for the synthesizer, an internal adapt charge pump provides higher current at pin 45 of U201 to put synthesizer within the lock range. The required frequency is then locked by normal mode charge pump at pin 43 . Both the normal and adapt charge pumps get their supply from the capacitive voltage multiplier which is made up of C258, C259, C228, triple diode CR201 and level shifters U210 and U211.
THEORY OF OPERATION Voltage Controlled Oscillator (VCO) (Refer to Figure 2-5 and the Voltage Controlled Oscillator schematic diagram) The VCOBIC (U241) in conjunction with the Fractional-N synthesizer (U201) generates RF in both the receive and the transmit modes of operation. The TRB line (U241 pin 19) determines which oscillator and buffer will be enabled.
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Frequency Generation Circuitry Table 2-1 Level Shifter Logic Desired AUX 4 AUX 3 Mode High (@3.2V) High (@4.8V) High Battery Saver Hi-Z/Float (@2.5V) In the receive mode, U241 pin 19 is low or grounded. This activates the receive VCO by enabling the receive oscillator and the receive buffer of U241.
Chapter 3 TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Receiver (Sheet 1 of 2) START Bad SINAD Bad 20dB Quieting No Recovered Audio udio Check Controller at pin 27 of U301? Spray of inject 1st IF into XTAL Filter IF Freq: 45.1MHz Check Q320 bias circuitry for faults.
TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Receiver (Sheet 2 of 2) Inject RF into J101 Q302 Trace IF signal collector OK? IF Signal from L311 to IF signal at L311? Q302. Check for present? bad XTAL filter. Before replacing U301, check U301 voltages;...
Troubleshooting Flow Chart for Transmitter Troubleshooting Flow Chart for Transmitter START No Power Is There B+ Bias for Check Q111 Ant switch CR101 Is Control Voltage Is Current Check PCIC High or Low at C119 High 1. Check Pin Diodes Check Drive to 2.
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Chapter 4 PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards Controller Circuits The 300-350MHz circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This Chapter shows the schematics for the 300R1 circuits only, refer to the Controller section for details of the related Controller circuits.The PCB component layouts and the Parts Lists in this Chapter show both the Controller and 300R1 circuit components.
PCB 8485726Z01 - Parts List 4-11 PCB 8485726Z01 - Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola Description C204 2104993J02 CAP MONO. CERAMIC (2.2UF) C294 2113743L05 CAP CHIP 330 PF 10% X7R...
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PCB 8485726Z01 - Parts List 4-12 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C444 2113743N50 CAP CHIP 100 PF 5% COG CR303 4880154K03 SOT MMBD353 RH DIODE DUAL...
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8485726Z01 PC BOARD UHF BAND 3 R407 0662057N19 RES. CHIP 68K 5% 20X40 SH202 2680511Z01 SHIELD, SYNTHESIZER * Motorola Depot Servicing only R409 0662057M98 RES CHIP 10K 5% 20X40 SH241 2680513Z01 SHIELD, VCO TOP Reference designators with an asterisk indicate...
PCB 8485726Z04 - Parts List 4-22 PCB 8485726Z04 - Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola Description C204 2104993J02 CAP MONO. CERAMIC (2.2UF) C295 2113743N50 CAP CHIP 100 PF 5% COG...
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PCB 8485726Z04 - Parts List 4-23 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C444 2113743N50 CAP CHIP 100 PF 5% COG CR251 4862824C01 DIODE VARACTOR IT363 L203...
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8485726Z04 PC BOARD UHF BAND 3 R415 0662057V26 RES CHIP 91K 1% 1/16W SH101 2680510Z01 SHIELD, PA * Motorola Depot Servicing only R416 0662057M98 RES. CHIP 10K 5% 20X40 SH201 2680511Z01 SHIELD, SYNTHESIZER Reference designators with an asterisk indicate R418 0662057M01 RES.
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Professional Radio GP Series Service Maintainability Issue: November 2004...
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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 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 Piece Parts .....................1-2 2.5 Technical Support...................1-3 2.6 Related Documents ..................1-3 3.0 Radio Model Information..................1-4 Chapter 2...
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. UK/Ireland - Richard Russell France - Lionel Lhermitte Telephone: +44 (0) 1256 488 082 Telephone: +33 1 6929 5722...
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 portable radio model number and its specific characteristics. Table 1-1 Radio Model Number (Example: MDH25KDC9AA3AE) 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.
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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Chip Components Use either the RLN4062 Hot-Air Repair Station or the Motorola 0180381B45 Repair Station for chip component replacement. When using the 0180381B45 Repair Station, select the TJ-65 mini-thermojet hand piece. On either unit, adjust the temperature control to 370 °C (700 °F), and adjust the airflow to a minimum setting.
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MAINTENANCE Shields Removing and replacing shields will be done with the R1070 station with the temperature control set to approximately 215°C (415°F) [230°C (445°F) maximum]. ❏ To remove the shield: Place the circuit board in the R1070 circuit board holder. Select the proper heat focus head and attach it to the heater chimney.
1. Unless otherwise stated, resistances are in Ohms (k = 1000), and capacitances are in picofarads (pF) or microfarads (µF). 2. DC voltages are measured from point indicated to chassis ground using a Motorola DC multimeter or equivalent. Transmitter measurements should be made with a 1.2 µF choke in series with the voltage probe to prevent circuit loading.
Table 3-1 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 lists the recommended tools used for maintaining this family of radios. These tools are also available from Motorola.. Table 3-2 Recommended Test Tools Motorola Part Description Application Number 6680702Z01 Chassis opener and knob Disassembly tool removal tool.
Test Equipment Test Equipment Table 3-3 lists test equipment required to service the radio and other two-way radios. Table 3-3 Recommended Test Equipment Motorola Part Description Characteristics Application Number R2600_ Comms System Analyzer This monitor will Frequency/deviation meter and (non MPT).
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SERVICE AIDS Motorola Part Description Characteristics Application Number * R1440_ Wattmeter, Thruline 50-Ohm, Transmitter power output ±5% accuracy measurements. * 0180305F14 Plug-in Element 10W, 25 - 60MHz * 0180305F29 Plug-in Element 5W, 100-250MHz * 0180305F38 Plug-in Element 5W, 200-500MHz * 0180305F46...
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Professional Radio GP Series Keypad and Flex Service Information Issue: November 2004...
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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 Keypad and Flexible Connectors .................1-1 1.1 Keypad ......................1-1 1.2 Flexible Connectors..................1-1 2.0 Troubleshooting Chart ..................1-2 Chapter 2 PCB / SCHEMATICS / PARTS LISTS 1.0 Allocation of Schematics and Circuit Boards ............2-1 1.1 Flexible Connectors..................2-1 1.2 Keypad PCBs ....................2-1 2.0 PCB/Schematic Diagrams and Parts List: Flexes..........2-3...
Chapter 1 THEORY OF OPERATION Keypad and Flexible Connectors Keypad The keypad block diagram is shown in Figure 1-1. U602 is a comparator that will compare the voltage when any one of the keypad row or keypad column keys is being pressed. Therefore when a key is being pressed, it will send a message to the microprocessor through the output (KEY_INT) telling it that a key has been pressed.
THEORY OF OPERATION Troubleshooting Chart Disconnect and Display reconnect 18-pin flex if still Off Disconnect and Keypad reconnect 40-pin flex Figure 1-2 Keypad Board Troubleshooting Chart...
Chapter 2 PCB / SCHEMATICS / PARTS LISTS Allocation of Schematics and Circuit Boards The printed circuit boards (PCB) and schematic diagrams related to the Flexible Connectors and the Keypads are shown in the tables below: Flexible Connectors Table 2-1: Keypad /Controller Flex Flex : 8480475Z02 Flex...
2-10 PCB/Schematic Diagrams and Parts List: Keypad PCB 8480682Z04 - Parts List Circuit Motorola Description Part No. Circuit Motorola Description Q604 4813824A10 NPN 40V .2A GEN PURP Part No. Q605 4813824A10 NPN 40V .2A GEN PURP C601 2113743N50 100 PF 5%...
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Professional Radio GP Series Power Distribution and Controller Service Information Issue: November 2004...
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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 ....................1-2 3.1 Controller Architecture..................1-2 3.2 MCU Digital Architecture ................1-2 3.3 Real Time Clock .....................1-3 3.4 ModB/Vstby Supply ..................1-4 3.5 Audio/Signaling Architecture ................1-4 Chapter 2 TROUBLESHOOTING CHARTS 1.0 300R1 Controller....................2-1...
Chapter 1 THEORY OF OPERATION Overview This Chapter provides a detailed theory of operation for the power distribution and controller circuits in the radio. The components for 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 for these circuits. Radio Power Distribution Accessories 20 pin Connector...
THEORY OF OPERATION Controller Circuits Controller Architecture The controller board is the central interface between the various subsystems of the radio. It is separated into MCU digital and audio/signalling architectures as shown in Figure 1-2. External Microphone To Synthesizer Internal Microphone 16.8 MHz Reference Clock...
THEORY OF OPERATION A MOSFET Q416 switches in the LiO supply when Vdd is removed. Q416 also provides isolation from BOOT_CTRL function in the event of radio program flashing. The 3.3V regulator charges the Lithium battery. ModB/Vstby Supply The supply to the ModB/Vstby pin varies depending on the conditions listed in Table 1-2. Table 1-2 ModB/Vstby Supply Modes Condition Circuit Operation...
Chapter 2 TROUBLESHOOTING CHARTS 300R1 Controller MCU Check Press PTT. Red LED does not Before replacing light up Power Up Not able to pro- MCU, check SPI Audio at Alert Tone gram RF Board AUDIO clock, SPI data, AudioPA J403 Audio and RF IC select (U420) at Pin 2 &...
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TROUBLESHOOTING CHARTS VHF Controller (except models with PCB 8486473Z04 MCU Check Press PTT. Red LED does not Before replacing light up Power Up Not able to pro- MCU, check SPI Audio at Alert Tone gram RF Board AUDIO clock, SPI data, AudioPA J403 Audio and RF IC select...
VHF Controller (for models with PCB 8486473Z04) VHF Controller (for models with PCB 8486473Z04 MCU Check Press PTT. Red LED does not Before replacing light up Power Up Not able to pro- MCU, check SPI Audio Alert Tone gram RF Board AUDIO clock, SPI data, at Audio PA...
TROUBLESHOOTING CHARTS Lowband Controller MCU Check Press PTT. Red LED does not Before replacing light up Power Up Not able to pro- MCU, check SPI Alert Tone gram RF Board AUDIO Audio at clock, SPI data, J403 Audio AudioPA and RF IC select at Pin 2 &...
Chapter 3 CONTROLLER SCHEMATICS Allocation of Schematics and Circuit Boards 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 Parts Lists.
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3-40 Controller - Set 6 (PCB 8486473Z04) Intentionally left blank...
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Professional Radio GP Series VHF (136-174MHz) Service Information Issue: November 2004...
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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 MODEL CHART AND TECHNICAL SPECIFICATIONS 1.0 GP320/GP340/GP360/GP380 Model Chart............1-1 2.0 GP140 Model Chart .....................1-2 3.0 GP640/GP680 Model Chart .................1-2 4.0 GP1280 Model Chart ...................1-3 5.0 GP240/GP280/GP540/GP580 Model Chart............1-4 6.0 Technical Specifications ..................1-5 Chapter 2 THEORY OF OPERATION 1.0 Introduction ......................2-1 2.0 VHF Transmitter....................2-1 2.1 Power Amplifier ....................2-1...
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Chapter 4 VHF PCB/SCHEMATICS/PARTS LISTS 1.0 Allocation of Schematics and Circuit Boards ............4-1 1.1 Controller Circuits................... 4-1 1.2 Voice Storage Facility..................4-1 2.0 VHF PCB 8486062B12 / Schematics ..............4-5 3.0 VHF PCB 8486062B12 Parts List ..............4-13 4.0 VHF PCB 8486101B09 / Schematics (GP1280)..........4-17 5.0 VHF PCB 8086101B09 Parts List (GP1280) .............
MODEL CHART AND TECHNICAL SPECIFICATIONS GP140 Model Chart Professional GP140 (VHF) Model Description MDH25KDC9AA3_E GP140 VHF 136-174 MHz 5W 16 Ch Item Description PMLE4109_ *GP140 UHF Back Cover Kit 6864110B25 GP140 Basic User Guide PMAD4023_ VHF 14cm (150-161 MHz) Antenna HNN9008_ Battery, NiMH Standard x = Indicates one of each is required.
GP1280 Model Chart GP1280 Model Chart Professional GP1280 (VHF) Model Description MDH25KDN9CK8_E GP1280 VHF 136-174 MHz 5W Item Description PMLD4120_ *GP1280 VHF Back Cover Kit 6864110B20 GP1280 Basic User Guide PMAD4023_ VHF 14cm (150-161 MHz) Antenna HNN9008_ Battery, NiMH Standard x = Indicates one of each is required.
Technical Specifications Technical Specifications Data is specified for +25°C unless otherwise stated. General Specifications Channel Capacity GP140 GP240, GP280 128 in conventional Mode GP320 GP340 GP360, GP380 GP540, GP580 128 in conventional Mode GP640, GP680, GP1280 16 (Conventional) Power Supply Rechargeable battery 7.5v Dimensions: H x W x D (mm) Height excluding knobs GP140/GP240/320/340/360/380/...
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MODEL CHART AND TECHNICAL SPECIFICATIONS Transmitter 136-174 *Frequencies - Full Bandsplit Channel Spacing 12.5/20/25 kHz Frequency Stability ±2.5 ppm (-25°C to +55°C, +25° Ref.) Power 136 - 174 MHz:1-5W ±2.5 @ 12.5 kHz Modulation Limiting ±4.0 @ 20 kHz ±5.0 @ 25 kHz FM Hum &...
Chapter 2 THEORY OF OPERATION Introduction This Chapter provides a detailed theory of operation for the VHF circuits in the radio. For details of the theory of operation and trouble shooting for the the associated Controller circuits refer to the Controller Section of this manual.
THEORY OF OPERATION This RF power amplifier is capable of supplying an output power of 0.3W (pin 6 and 7) with an input signal of 2mW (3dBm) (pin16). The current drain is typically around 130mA while operating in the frequency range of 136-174MHz. The LDMOS PA is capable of supplying an output power of 7W with an input signal of 0.3W.
VHF Receiver (for all models except those with PCB8486473Z04) VHF Receiver (for all models except those with PCB8486473Z04) The VHF receiver consists of a front end, back end, and automatic gain control circuits. A block diagram of the VHF receiver is shown in Figure 2-2. Detailed descriptions of these features are contained in the paragraphs that follow.
THEORY OF OPERATION Both the pre and post-RF amplifier varactor tuned filters have similar responses. The 3 dB bandwidth of the filter is about 12 MHz. This enables the filters to be electronically controlled by using a single control voltage which is DACRx. The output of the post-RF amplifier filter is connected to the passive double balanced mixer which consists of T3301, T3302, and CR3301.
VHF Receiver (for all models except those with PCB8486473Z04) Automatic Gain Control (AGC) ( Refer to the Receiver Front End and Receiver Back End schematic diagrams ) The front end automatic gain control circuit provides automatic reduction of gain of the front end RF amplifier via feedback.
THEORY OF OPERATION Receiver (for models with PCB 8486473Z04) Antenna Pin Diode Varactor Varactor Antenna Crystal RF Amp Mixer IF Amp Tuned Filter Tuned Filter Switch RF Jack Filter First LO from VCO Control Voltage from ASFIC U3220 Limiter Demodulator Recovered Audio RSSI 455kHz...
Receiver (for models with PCB 8486473Z04) Both the pre and post-RF amplifier varactor tuned filters have similar responses. The 3 dB bandwidth of the filter is about 12 MHz. This enables the filters to be electronically controlled by using a single control voltage which is DACRx . The output of the post-RF amplifier filter is connected to the passive double balanced mixer which consists of T3301, T3302 and CR3301.
THEORY OF OPERATION Automatic Gain Control (AGC) ( Refer to the Receiver Front End and Receiver Back End schematic diagrams ) The front end automatic gain control circuit provides automatic reduction of gain of the front end RF amplifier via feedback. This prevents overloading of backend circuits and is achieved by drawing some of the output power from the RF amplifier output.
Frequency Generation Circuit In addition to the VCO, the synthesizer must interface with the logic and ASFIC circuitry. Programming for the synthesizer is accomplished through the data, clock and chip select lines (pins 7, 8 and 9) from the microprocessor, U409. A 3.3V dc signal from pin 4 indicates to the microprocessor that the synthesizer is locked.
2-10 THEORY OF OPERATION Voltage Controlled Oscillator (VCO) ( Refer to Figure 2-6 and the VHF Voltage Controlled Oscillator schematic diagram) The VCOB IC (U3801), shown in Figure 2-6, in conjunction with the Fractional-N synthesizer (U3701) generates RF in both the receive and the transmit modes of operation. The TRB line (U3801 pin 19) determines which oscillator and buffer are enabled.
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Frequency Generation Circuit 2-11 Table 2-1 Level Shifter Logic Desired AUX 4 AUX 3 Mode n.u. High (@3.2V) High (@3.2V) n.u. Battery Saver n.u. Hi-Z/Float Hi-Z/Float (@1.6V) (@1.6V) In the receive mode, U3801 pin 19 is low or grounded. This activates the receive VCO by enabling the receive oscillator and the receive buffer of U3801.
2-12 THEORY OF OPERATION Voice Storage (GP1280) ( Refer to Figure 2-7 and the VHF Voice Storage schematic diagram) The Voice Storage feature is offered as standard in the GP1280 and as an Option board for GP340/GP360/GP380 and GP640/GP680. The Voice Storage feature enables users to: Record and Playback Personal Memo (Reminders, Notes, etc.).
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Voice Storage (GP1280) 2-13 Audio routing to the Voice Storage circuitry during receive message recording, message playback, personal memo recording and voice prompt transmit over the air are as follows: Received Message Recording The receive audio is tapped from the Rx_Aud_Rtn pin of the ASFIC_CMP during receive mode. Message Playback Message playback is via the FLAT_RX_SND pin of ASFIC_CMP.
Chapter 3 TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Receiver, for all models except those with PCB 8486473Z04 (Sheet 1 of 2) START Bad SINAD Bad 20dB Quieting No Recovered Audio udio Check Controller at pin 27 of U3220? Spray of inject 1st IF into XTAL Filter IF Freq: 45.1MHz Check Q3270 bias...
TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Receiver for all models except those with PCB 8486473Z04 (Sheet 2 of 2) Inject RF into J3501 Q3200 Trace IF signal collector OK? IF Signal from C3200 to IF signal at C3200? Q3200. Check for present? bad XTAL filter.
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Troubleshooting Flow Chart for Receiver, for models with PCB 8486473Z04 (Sheet 1 of 2) Troubleshooting Flow Chart for Receiver, for models with PCB 8486473Z04 (Sheet 1 of 2) START Bad SINAD Bad 20dB Quieting No Recovered Audio Check Controller Audio at pin (in the case of no audio) 8 of U3220? OR ELSE go to “B”...
TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Receiver, for models with PCB 8486473Z04 (Sheet 2 of 2) Inject RF into J3501 Trace IF signal Q3200 collec- from L3200 to IF Signal at tor OK? Q3200. Check for L3200? IF signal bad XTAL filter. present? Before replacing U3220, check...
Troubleshooting Flow Chart for Transmitter Troubleshooting Flow Chart for Transmitter START No Power There B+ Bias for Check Q3561 Ant switch D3521 Control Voltage High Check PCIC Current or Low at TP3502 High 1. Check Pin Diodes Check Drive to 2.
TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Synthesizer 3.3V Start at U3701 Check pins 5, 20, U3201, 34 & 36 L3731 Visual Check D3701, Correct check of the D3702, U3701, Problem Board C3701 - C3707 Is U3701 16.8MHz 16.8MHz at pin 6 of Replace Pin47 AT = 13 signal at...
TROUBLESHOOTING CHARTS Troubleshooting Flow Chart for Receive Message/Personal Memo Recording Cannot Receive Message Personal Memo Recording Check menu Turn on Check Mic I/P at whether record “Record Incoming J403-18 any audio? incoming messages Call” turned on Check Spkr/Mic Flex Connection J403 Check J400-34 Any audio?
Chapter 4 VHF PCB/SCHEMATICS/PARTS LISTS Allocation of Schematics and Circuit Boards Controller Circuits 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 only, refer to the Controller section for details of the related Controller circuits .
VHF PCB/SCHEMATICS/PARTS LISTS Table 4-2 VHF GP1280 Diagrams and Parts Lists PCB : 8486101B09 Main Board Top Side Page 4-17 8486101B09 Main Board Bottom Side Page 4-18 8486101B10 Main Board Top Side Page 4-31 8486101B10 Main Board Bottom Side Page 4-32 SCHEMATICS Controls and Switches Page 4-7...
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Allocation of Schematics and Circuit Boards Table 4-4 VHF GP1280 Diagrams and Parts Lists PCB : 8486101B11 Main Board Top Side Page 4-55 8486101B11 Main Board Bottom Side Page 4-56 SCHEMATICS Controls and Switches Page 4-39 Receiver Front End Page 4-40 Receiver Back End Page 4-41 Synthesizer...
VHF PCB 8486062B12 Parts List 4-13 VHF PCB 8486062B12 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No Part No Part No Circuit Motorola Description C3301 2113743N20 5.6 PF +-.5PF COG C3534 2113740F19 CHIP CAP, CER 4.7PF...
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4-14 VHF PCB 8486062B12 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No C428 2113743M24 100000 PF +80-20% Y5V C511 2113743N50 100 PF 5% COG L3305 2462587T35...
VHF PCB 8086101B09 Parts List (GP1280) 4-21 VHF PCB 8086101B09 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description (GP1280) Part No Part No Part No C3276 2113743N42 47.0 PF 5% C3519 2113740F35 REEL CL1 +/-30 22 C3721 2113743E20 CHIP.
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4-22 VHF PCB 8086101B09 Parts List (GP1280) Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No C4001 2113743N50 100 PF 5% C466 2113743N50 100 PF 5% CR3301 4802245J42 RING QUAD SOT-143 PKG...
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VHF PCB 8086101B09 Parts List (GP1280) 4-23 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No Q3721 4802245J50 DUAL NPN/PNP UMC5N R3314 0662057M26 10 5% 20X40 R3811 0662057M50 100 5% 20X40...
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4-24 VHF PCB 8086101B09 Parts List (GP1280) Circuit Motorola Description * Motorola Depot Servicing only Part No Reference designators with an asterisk indicate SH3701 2680511Z01 SHIELD SYNTHESIZER components which are not field replaceable SH3702 2680511Z01 SHIELD SYNTHESIZER because they need to be calibrated with...
VHF PCB 8486062B14 Parts List 4-27 VHF PCB 8486062B14 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No Part No Part No C3280 2113743L41 10000 PF 10% C3533 2113740F24 REEL CL1+/-30 7.5 C3752 2113743L17 1000 PF 10%...
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4-28 VHF PCB 8486062B14 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No C427 2113743N50 100 PF 5% COG C4021 2113743L17 1000PF 10% not in GP320 PB502...
VHF PCB 8486101B10 Parts List (GP1280) 4-33 VHF PCB 8486101B10 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description (GP1280) Part No Part No Part No C3276 2113743N42 47.0 PF 5% C3519 2113740F35 REEL CL1 +/-30 22 C3721 2113743E20 CHIP.
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4-34 VHF PCB 8486101B10 Parts List (GP1280) Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No C4001 2113743N50 100 PF 5% C466 2113743N50 100 PF 5% CR3301 4802245J42 RING QUAD SOT-143 PKG...
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VHF PCB 8486101B10 Parts List (GP1280) 4-35 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No Q3721 4802245J50 DUAL NPN/PNP UMC5N R3316 0662057M66 470 5% 20X40 R3817 0662057M01 0 5% 20X40...
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4-36 VHF PCB 8486101B10 Parts List (GP1280) Circuit Motorola Description * Motorola Depot Servicing only Part No Reference designators with an asterisk indicate SH3701 2680511Z01 SHIELD SYNTHESIZER components which are not field replaceable SH3702 2680511Z01 SHIELD SYNTHESIZER because they need to be calibrated with SH3801 2680513Z01 SHIELD VCO TOP specialized factory equipment after installation.
VHF PCB 8486062B16 Parts List 4-45 11.0 VHF PCB 8486062B16 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No Part No Part No C3275 2113743N44 56pF C3521 2111078B51 220pF C3722 2113743E20 0.10uF, 10% Circuit Motorola Description...
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4-46 VHF PCB 8486062B16 Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No C402 2113928N01 0.1uF, 10% C467 2113928N01 0.1uF, 10% D3701 4802233J09 Triple diode L3551 2479990N01 43.67nH...
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VHF PCB 8486062B16 Parts List 4-47 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No R3200 0662057M54 R3505 0662057M62 R3831 0662057M98 R463 0662057M61 R3201 0662057M82 2200 R3506 0662057B62 R3832...
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16.8MHz Xtal oscillator (SMD) 5480678Z01 PCB Bar Code Label 8486062B16 VHF main PC Board * Motorola Depot Servicing only Reference designators with an asterisk indicate components which are not field replaceable because they need to be calibrated with specialized factory equipment after installation.
VHF PCB 8486062B17 4-51 13.0 VHF PCB 8486062B17 Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No Part No Part No Circuit Motorola Description C3276 2113743N42 47pF C3523 2111078B44 120pF C3724 2311049A08 Part No C3277 2113743N48 82pF C3524...
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4-52 VHF PCB 8486062B17 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No C4020 2113743L17 1000pF, 10% C471 2113743L09 470pF, 10% D3702 4802233J09 Triple diode L3552 2479990A02 7.66nH, 10%...
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VHF PCB 8486062B17 4-53 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No Part No Part No Part No R3201 0662057M82 2200 R3506 0662057B62 R3832 0662057N01 R471 0662057M92 5600 R3202 0662057M90 4700 R3507 0662057B62 R3833...
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PCB Bar Code Label 8486062B16 VHF main PC Board 8486062B17 VHF main PC Board * Motorola Depot Servicing only Reference designators with an asterisk indicate components which are not field replaceable because they need to be calibrated with specialized factory equipment after installation.
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VHF PCB 8486473Z04 Radio Parts List 4-69 17.0 VHF PCB 8486473Z04 Radio Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Parts List Part No. Part No. Part No. Circuit Motorola C3302 2113743N54 150pF C3502 2113743N38 33pF C3560 2311049A07 Description Part No.
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4-70 VHF PCB 8486473Z04 Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C3734 2113743L41 10000pF C383 2113743N43 51pF 0.1uF (not placed in C483 2113743L09 470pF...
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VHF PCB 8486473Z04 Radio Parts List 4-71 Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. D3551 4880973Z02 Pin Diode L3503 2462587V32 68nH L505 2462587Q42 390nH R3220 NOT PLACED...
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4-72 VHF PCB 8486473Z04 Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. R3505 0662057M62 R3727 0662057N23 100K R3835 0662057N15 R448 0662057M98 R3506 0662057B62 R373 NOT PLACED...
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16.8 MHz Crystal Oscillator U3221 5109522E10 Inverter IC 8486473Z04 VHF PC Board U3501 5185130C65 ASFIC CMP IC * Motorola Depot Servicing only U3502 5185765B26 LDMOS Driver IC Reference designators with an asterisk indicate U3503 5185963A15 PCIC components which are not field replaceable...
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4-74 VHF PCB 8486473Z04 Radio Parts List Intentionally Left Blank...
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Professional Radio GP Series Lowband (29.7-42MHz and 35-50MHz) Service Information Issue: November 2004...
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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 MODEL CHART AND TECHNICAL SPECIFICATIONS 1.0 GP340/GP380 Model Chart .................1-1 2.0 Technical Specifications ..................1-2 Chapter 2 THEORY OF OPERATION 1.0 Lowband Transmitter ...................2-1 1.1 Power Amplifier (PA) ..................2-1 1.2 Antenna Switch....................2-2 1.3 Harmonic Filter ....................2-2 1.4 Antenna Matching Network ................2-2 1.5 Power Control Integrated Circuit (PCIC) ............2-2 1.6 Temperature Cut Back Circuit ................2-2...
MODEL CHART AND TECHNICAL SPECIFICATIONS Technical Specifications Data is specified for +25°C unless otherwise stated. General Specifications Channel Capacity GP340 GP380 Power Supply Rechargeable battery 7.5v Dimensions: H x W x D (mm) Height excluding knobs With standard high capacity NiMH battery 137 x 57.5 x 37.5 With ultra high capacity NiMH battery 137 x 57.5 x 40.0...
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Technical Specifications Transmitter LB1 29.7-42 MHz *Frequencies - Full Bandsplit LB2 35-50 MHz Channel Spacing 12.5/20/25 kHz Frequency Stability ±10ppm (-25°C to +55°C, +25° Ref.) 1-6W Power ±2.5 @ 12.5 kHz Modulation Limiting ±4.0 @ 20 kHz ±5.0 @ 25 kHz FM Hum &...
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MODEL CHART AND TECHNICAL SPECIFICATIONS...
Chapter 2 THEORY OF OPERATION Introduction This chapter provides a detailed theory of operation for the radio RF circuits. Refer to the relevant section of this manual for details of the operation of the Controller Circuits. Lowband Transmitter ( Refer to Figure 2-1 and the Lowband Transmitter schematic diagram ) The Lowband transmitter consists of the following basic circuits : ■...
THEORY OF OPERATION The LDMOS PA is capable of supplying an output power of 8W with an input signal of 0.3W. The current drain is typically 2000 mA while operating in the frequency range of 29.7 - 50 MHz. The final stage gate is bias by a voltage from PCIC pin 24.
Lowband Receiver Lowband Receiver ( Refer to Figure 2-2 and the Receiver Front End and Receiver Back End schematic diagrams) The Lowband receiver consists of a front end, back end, and automatic gain control circuits. Detailed descriptions of these stages are contained in the paragraphs that follow. Antenna Lowpass Antenna...
THEORY OF OPERATION Receiver Back-End ( Refer to the Receiver Back End schematic diagram ) The output of crystal filter FL301 is connected to the input of IF amplifier transistor U301. Components L303 and C348 and R301 form the termination for the crystal filter and the signal is coupled to one gate of U301 by C303.
Frequency Generation Circuit Frequency Generation Circuit ( Refer to Figure 2-3, the Synthesizer and Voltage controlled Oscillator schematic diagrams ) The frequency generation circuit is composed of Low Voltage Fractional-N synthesizer U205 and discrete RX VCO, TX VCO and buffers as well other supporting circuitry. The synthesizer block diagram illustrates the interconnect and support circuitry used in the region.
THEORY OF OPERATION Synthesizer (Refer to Figure 2-4 and the Synthesizer schematic diagram) The Fractional-N synthesizer, shown in Figure 2-4, uses a 17.0 MHz crystal (Y201) to provide a reference for the system. Along with being used in the LVFracN, the 17.0 MHz signal is provided at pin 19 of U205 for use by the ASFIC and LVZIF.
Frequency Generation Circuit Voltage Controlled Oscillator (VCO) ( Refer to the Voltage Controlled Oscillator schematic diagram ) 4.2.1 Receive VCO The receive VCO is a Colpitts type design and using two active devices in parallel, Q202 and Q204. The oscillator is powered off of the 4.3 volt super filter supply when the AUX3 line goes low. The oscillator operates from 139 to 152 MHz for range 1 and 145 to 160 MHz for range 2.
Chapter 3 TROUBLESHOOTING CHARTS Receiver (Sheet 1 of 2) START Bad SINAD Bad 20dB Quieting No Recovered Audio Audio at Check Controller pin 27 of U303? Spray of inject 1st IF into XTAL Filter IF Freq: 109.65 MHz Check Q301 bias circuitry for faults.
TROUBLESHOOTING CHARTS Receiver (Sheet 2 of 2) Inject RF into J101 Trace IF signal U301 drain signal at from L301 to U301. L301? Check for bad IF signal XTAL filter. present? Before replacing U303, check U303 voltages; 1st LO O/P trace IF signal Signal Check FGU...
Transmitter Transmitter START No Power Is control voltage Is Current Check PCIC at U101 Pin 1 > 5 ~ 2 A? Check input to U101, Pin 16 1. Check Pin Diodes 2. Check Harmonic Filter 3. Check PA Bias Troubleshoot Is voltage >...
TROUBLESHOOTING CHARTS Synthesizer Check U400 3.3V at U205 Start and L225 pins 5, 20, 34 & 36 Visual Correct check of the Problem Board OK? Check C247, C249, Is U205 Is 17.0 MHz 17.0MHz C283-C286, Replace Pin 47 at D210, D211, Signal at signal at U205...
Voltage Controlled Oscillator Voltage Controlled Oscillator No RX LO or No No TX LO or No signal at U205 Pin signal at U205 Pin 32 in RX 32 in TX Check signal at Check signal at collector of Q201 collector of Q201 Check L204, L211, L212, Level >...
Chapter 4 LOWBAND PCB/SCHEMATICS/PARTS LIST Allocation of Schematics and Circuit Boards Controller Circuits The Lowband circuits are contained on the printed circuit board (PCB) which also contains the Controller circuits. This chapter shows the schematics for the Lowband circuits only, refer to the Controller section for details of the related Controller circuits.
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