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 prod-...
Page 3
Document History Document History The following major changes have been implemented in this manual since the previous edition: Edition Description Date 6804111J47-D Updated the mechanical parts list and exploded view. Nov. 2003...
Page 4
Document History THIS PAGE INTENTIONALLY LEFT BLANK...
Your Motorola two-way radio has an RF exposure information label in the battery compartment. This user safety booklet includes useful information about RF exposure and helpful instructions on how to control your RF exposure.
Page 6
RF exposures decrease with distance from the antenna. • For body-worn operation, always place the radio in a Motorola-approved clip, holder, holster, case, or body harness for this product. Using non–Motorola-approved accessories may result in exposure levels which exceed the FCC’s occupational/controlled environment RF exposure lim- its.
Page 7
Safety Information Medical Devices Pacemakers The Advanced Medical Technology Association (AdvaMed) recommends that a minimum separation of 6 inches (15 centimeters) be maintained between a handheld wireless radio and a pacemaker. These recommendations are consistent with those of the U.S. Food and Drug Administration. Persons with pacemakers should: •...
viii Safety Information Operational Warnings For Vehicles With An Air Bag Do not place a portable radio in the area over an air bag or in the air bag deployment area. Air bags inflate with great force. If a portable radio is placed in the air bag deployment area and the air bag inflates, the radio may be propelled with great force and cause serious injury to occupants of the vehicle.
• Do not disassemble an FMRC Approved Product in any way that exposes the internal circuits of the unit. Radios must ship from the Motorola manufacturing facility with the hazardous atmosphere capability and FM Approval labeling. Radios will not be “upgraded” to this capability and labeled in the field. A modification changes the unit’s hardware from its original design configuration.
FMRC Approved model. Do Not Substitute Options or Accessories The Motorola communications equipment certified by Factory Mutual is tested as a system and consists of the FM Approved portable, FM Approved battery, and FM Approved accessories or options, or both. This FM Approved portable and battery combination must be strictly observed.
Table of Contents Section SAFETY INFORMATION Section 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 Piece Parts ..................... 1-2 2.4 Technical Support ..................1-3 3.0 Radio Model Information..................
Page 12
8.1 Configuring the Radio after Option Board Installation ........4-15 8.2 Additional Configuration required by the DTMF Option Board .....4-16 9.0 Mechanical View and Parts List .................4-17 9.1 GP88s Exploded View and Parts List ............4-17 Section 5 Transceiver Performance Testing 1.0 Introduction ......................5-1 2.0 Setup........................5-1...
Page 14
UHF Transmitter Schematic Diagram ..............9A-20 UHF Harmonic Filter Schematic Diagram............9A-21 UHF Radio Parts List ..................9A-22 8.0 Circuit Board/Schematic Diagrams and Parts List .......... 9A-25 UHF (403-470MHz) Main Board Top Side PCB No. 8480672Z04..... 9A-25 UHF (403-470MHz) Main Board Bottom Side PCB No. 8480672Z04 ....9A-26 UHF Controls And Switches Schematic Diagram ..........
Page 15
5.2 VCO - Voltage Controlled Oscillator............9B-10 6.0 Notes For All Schematics and Circuit Boards..........9B-12 7.0 Circuit Board/Schematic Diagrams and Parts List...........9B-13 VHF (136-174MHz) Main Board Top Side PCB No. 8480675Z01 .....9B-13 VHF (136-174MHz) Main Board Bottom Side PCB No. 8480675Z01 ....9B-14 VHF Controls And Switches Schematic Diagram..........9B-15 VHF Receiver Front End Schematic Diagram............9B-16 VHF Receiver Back End Schematic Diagram ............9B-17...
Page 16
4.0 Parts List for Speaker/Mic Assembly - 0104008J99 ..........10-2 Glossary of Terms ..................G-1...
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 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.
Technical support is available to assist the dealer/distributor in resolving any malfunction which may be encountered. Initial contact should be by telephone wherever possible. When contacting Motorola Technical Support, be prepared to provide the product model number and the unit’s serial number.
Table 1-1 Radio Model Number (Example: AZH34KDC9AA3) Type Model Freq. Power Physical Channel Feature Protocol Series Band Level Packages Spacing Level Unit 4-5W GP88s Programma- Conventional GP88s (136- MHz) (403- MHz) H = Portable AZ = Country Code...
Section 3 SERVICE AIDS Recommended Test Tools Table 3-1 lists the tools recommended for working on this family of radios. These tools are also available from Motorola. Table 3-1 Recommended Test Tools Motorola Part No. Description Application 6680387A59 Extractor, 2-contact...
Service Aids Service Aids Table 3-2 lists service aids recommended for working on the GP88s Radios. While all of these items are available from Motorola, most are standard shop equipment items, and any equivalent item capable of the same performance may be substituted for the item listed.
Test Equipment Test Equipment Table 3-3 lists test equipment required to service the GP88s Radios and other two-way radios. Table 3-3 Recommended Test Equipment Motorola Part Description Characteristics Application R2000, R2400, Service Monitor This monitor will Frequency/deviation meter or R2001 with...
Section 4 MAINTENANCE Introduction This chapter provides details about the following: Preventive maintenance (inspection and cleaning) • • Safe handling of CMOS and LDMOS devices • • • Disassembly and reassembly of the radio • Repair procedures and techniques • •...
Wear a conductive wrist strap in series with a 100k resistor to ground. (Replacement • • wrist straps that connect to the bench top covering are Motorola part number RSX- 4015.) Do not wear nylon clothing while handling CMOS devices.
When damaged parts are replaced, identical parts should be used. If the identical replacement part is not locally available, check the parts list for the proper Motorola part number and order the part from the nearest Motorola Communications parts center listed in the “Piece Parts” section of this manual.
• • keypad retainer tool • • TORX™ T6 screwdriver • • If a unit requires more complete testing or service than is customarily performed at the basic level, send this unit to a Motorola Authorized Service Center.
Radio Disassembly — Detailed The following disassembly procedures should be performed only if necessary: Chassis Assembly Disassembly (Paragraph 6.2) Keypad/Option Board Disassembly (Paragraph 6.3) Speaker, Microphone, and Wire Disassembly (Paragraph 6.4) PTT Disassembly (Paragraph 6.5) Control Top Disassembly (Paragraph 6.6) Radio Disassembly —...
Page 34
Radio Disassembly — Detailed Pull the volume and channel selector knobs off of their shafts. Remove the dust cover. Knobs Figure 4-2 Knob Removal NOTE Both knobs slide on and off. However, they are supposed to fit very tightly on their shafts. Separate the chassis from the internal electronics front cover assembly by using the chassis opener (part number 6680702Z01).
Radio Disassembly — Detailed Unplug the wires from the 4-pin connector. Jumper Flex Latch Wire Assembly 4-Pin Connector Figure 4-4 Unlatch Flex Connectors Chassis Assembly Disassembly Use a TORX™ screwdriver with a T6 head to remove the four screws holding the main board to the chassis.
Radio Disassembly — Detailed Remove the six small O-ring retainers from their slots in the chassis. Note the alignment of the retainers for reassembly. Remove the O-ring. Keypad/Option Board Disassembly If the disassembly of the keypad printed circuit board is required, open the catches on the keypad retainer and lift the wire assembly up.
Radio Disassembly — Detailed The keypad/option board, and the keypad, can be removed without the use of tools. Retainer Jumper Flex Keypad/Option Board Keypad Radio Housing Wire Assembly Figure 4-7 Removing the Keypad Retainer and Other Boards from the Radio Housing NOTE At this point, the Option Board Installation Procedure should be performed, if necessary.
4-10 Radio Disassembly — Detailed Insulator Speaker Retainer Felt Speaker Microphone Wire Connector Mic Boot Radio Housing Figure 4-8 Removal Speaker-Microphone Assembly When reassembling the microphone in its boot, make sure the microphone port faces the round hole in the bottom of the boot. PTT Disassembly If required, the PTT bezel, and the PTT seal assembly, can be disassembled using a small screwdriver, as follows:...
Radio Reassembly — Detailed 4-11 Control Top Disassembly To remove the control top assembly, place a screwdriver next to the antenna boss, and pry it against the top escutcheon. This will lift the top escutcheon away from the top of the front housing.
4-12 Radio Reassembly — Detailed Keypad Option Board, Microphone and Wire Reassembly Replace the keypad/option board. Insert the “top hooks” of the keypad retainer into the slots below the speaker in the front cover. Snap all four of the retainer arm tabs in place in the front cover. NOTE Pull the speaker-microphone wire out of harm’s way during reassembly.
Option Board Installation 4-13 Chassis and Front Cover Reassembly Align the chassis assembly end-to-end with the front cover assembly. Insert the tails of the jumper flex and wire assembly into their respective connectors at the bottom of the front cover. Push down the latches on the connectors to hold the flex circuit to the main board.
Page 42
4-14 Option Board Installation Retainer Jumper Flex Keypad/Option Board Wire Assembly Figure 4-12 Changing the Keypad/Option Board Reassemble the option board to the front cover assembly. Insert the jumper flex circuit into the connector on the option board. Notice the orientation of the flex circuit.
Option Board Installation 4-15 Configuring the Radio after Option Board Installation Connect the radio to the computer following instructions outlined in Section 6. Start up the CPS, and read the radio’s codeplug. Open the Radio Configuration dialog box, and proceed to the Option Board tab. From the pull-down menu, choose the option board type that you just installed (choose Simple Decoder for the DTMF option board).
4-16 Option Board Installation Additional Configuration required by the DTMF Option Board In the Tree View window of your CPS, expand the Signalling node. Also expand the DTMF System node. Open each of the DTMF System dialog boxes under this node, and fill in the relevant information pertinant to your DTMF system.
Mechanical View and Parts List 4-17 Mechanical View and Parts List GP88s Exploded View and Parts List Figure 4-16 GP88s Radio Exploded View...
Page 46
4-18 Mechanical View and Parts List Motorola Motorola Item Part Description Item Part Description Number Number See Section 2 Antenna 3380564Z01 Label, Warning 3680690Z01 Knob, Volume See Section Back Cover Kit including 9A & Section chassis main board 3680147S07 Knob, Frequency...
Section 5 TRANSCEIVER PERFORMANCE TESTING Introduction The radios have been prepared to meet published specifications through their manufacturing process, with the use of laboratory-quality test equipment of highest accuracy. The recommended field service equipment approaches the accuracy of the manufacturing equipment with a few exceptions.
Test Mode Test Mode RF Test Mode When the radio is operating in its normal environment, the radio’s microcontroller controls the RF channel selection, transmitter key-up, and receiver muting. However, when the unit is on the bench for testing, alignment or repair, it is removed from its normal environment. It cannot receive commands from its system and, therefore, the internal microcontroller will not key the transmitter nor unmute the receiver.
Page 49
Test Mode Table 5-3 Test Channel Spacing No. of BKC Channel Spacing 25 kHz 12.5 kHz 20 kHz Table 5-4 Test Frequencies Channel Selector Switch Test Channel Position 1 Low Power TX#1 or #8 136.025 403.025 8 High Power RX#1 or #8 136.025 403.025 2 Low Power...
Page 50
Test Mode Table 5-5 Receiver Performance Checks Test Communications Radio Test Set Comments Name Analyzer Reference Mode: PWR MON TEST MODE, PTT to continu- Frequency error to be Frequency 4th channel test frequency* Test Channel ous (during the ±200 Hz VHF Monitor: Frequency error 4 carrier performance...
Page 51
Test Mode Table 5-6 Transmitter Performance Checks Test Communications Radio Test Set Comments Name Analyzer Reference Mode: PWR MON TEST MODE, PTT to continu- Frequency error to be Frequency 4th channel test frequency* Test Channel ous (during the ±200 Hz VHF Monitor: Frequency error 4 carrier performance...
Page 52
Test Mode THIS PAGE INTENTIONALLY LEFT BLANK...
Section 6 RADIO TUNING AND PROGRAMMING Introduction This chapter provides an overview of the Professional Radios Customer Programming Software (CPS) and Universal Tuner which have been designed for use in a Windows 95 environment. Both these software will essentially cover all the functions of the traditional Radio Service Software (RSS) package.
Radio Tuning Setup Radio Tuning Setup A Windows 95 PC (personal computer) and Universal Tuner are required to tune the radio. To perform the tuning procedures, the radio must be connected to the PC, RIB (Radio Interface Box) and Universal Test Set as shown in figure below. Refer to online help files for the tuning procedures.
CPS Programming Setup CPS Programming Setup Refer to online help files for the CPS Programming procedures. Radio Test Box RLN4460A Battery Program/ Test Cable PMKN4004A Tx Data Data RLN-4008B Computer Interface Cable RIB Power Supply Figure 6-2 CPS Programming Setup Cloning Information Cloning is the process of copying the content of one radio (source radio) into another radio (target radio).
Page 56
Cloning Information THIS PAGE INTENTIONALLY LEFT BLANK...
Section 7 CONTROLLER INFORMATION Overview This section provides a detailed theory of operation for the radio and its components. Radio Power Distribution Accessory Jacks Keypad/Option Board Audio PA Vdda UNSWB+ Vdda Reg. Fuse SWB+ 7.5V Vddd Vdda Battery Reg. FRACTN ASFIC_CMP MCU Micro P, ROM LVZIF...
The controller board is the central interface between the various subsystems of the radio. It is separated into digital and audio architectures. The digital portion consists of a special Motorola microcontroller (HC11FL0). The audio power amplifier (Audio PA) and audio/signalling/filter/ companding IC (ASFIC_CMP) form the backbone of the audio/signalling architecture.
Controller Board Digital Architecture MCU configuration There is one common MCU architecture for low-tier as well as for the high-tier products. It covers the Conventional and Trunking portables. An open architecture system with the new HC11FL0 as the processor is used. Combinations of different size RAM, ROM and EEPROM are available for various application software.
Page 60
Controller Board THIS PAGE INTENTIONALLY LEFT BLANK...
Controller Schematics (403-470MHz for 8480672Z01 & 136-174MHz for 8480675Z01) Dual Vdd Single Vdd Regulator Scheme Regulator Scheme Prime Non Prime Non Prime Prime Jumpers Model Model Model Model R401 R402 IF_RED_LED_CTRL RED_LED RED_LED R403 IF_GREEN_LED_CTRL GREEN_LED GREEN_LED IF_SB1_CTRL R404 IF_SB2_CTRL IF_BATT_CODE_CTRL BATT_CODE BATT_CODE...
Section 8 KEYPAD BOARD INFORMATION Theory of Operation Keypad 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.
Transmitter 9A-3 Transmitter P C I C Antenna Vcontrol Vcontrol Jack Antenna Switch/ From VCO PA-Final Harmonic Filter/ Driver Stage Matching Network Figure 9-1 Transmitter Block Diagram General (Refer to Figure 9-1) The UHF transmitter contains five basic circuits: 1. power amplifier 2.
9A-4 Transmitter 3.1.2 Antenna Switch The antenna switch circuit consists of two PIN diodes (CR101 and CR102), a pi network (C107, L104 and C106). In the transmit mode, B+ at PCIC (U102) pin 23 will go low and turn on Q111 where a B+ bias is applied to the antenna switch circuit to bias the diodes "on".
Receiver 9A-5 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...
9A-6 Receiver The output of the post-RF amplifier filter which is connected to the passive double balanced mixer consists of T301, T302 and CR306. Matching of the filter to the mixer is provided by C381. After mixing with the first LO signal from the voltage controlled oscillator (VCO) using low side injection, the RF signal is down-converted to the 45.1 MHz IF signal.
Receiver 9A-7 Automatic Gain Control Circuit (Refer to UHF Receiver Front End Schematic Diagram on page 9A-16) 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.
Frequency Generation Circuitry 9A-9 Synthesizer (Refer to UHF Synthesizer Schematic Diagram on page 9A-18) The Fractional-N Synthesizer uses a 16.8MHz crystal (FL201) to provide a reference for the system. The LVFractN IC (U201) further divides this to 2.1MHz, 2.225MHz, and 2.4MHz as reference frequencies.
9A-10 Frequency Generation Circuitry VCO - Voltage Controlled Oscillator (Refer to UHF Voltage Controlled Oscillator Schematic Diagram on page 9A-19) AUX3 (U201 Pin2) Level Shifter AUX4 (U201 Pin3) Network U201 Pin 32 Prescaler Out TRB_IN Pin 20 Pin 19 Pin 12 Pin7 Rx-SW TX/RX/BS...
Page 87
Frequency Generation Circuitry 9A-11 The VCOBIC(U241) is operated at 4.54 V (VSF) and Fractional-N synthesizer (U201) at 3.3V. This difference in operating voltage requires a level shifter consisting of Q260 and Q261 on the TRB line. The operation logic is shown in Table 9-1. Table 9-1 Level Shifter Logic Desired AUX 4...
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 multime- ter or equivalent. Transmitter measurements should be made with a 1.2 µH choke in series with the voltage probe to prevent circuit loading.
Circuit Board/Schematic Diagrams and Parts List UHF Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola Description C172 2113740F51 100pF C276 2104993J02 2.2uF C340 2180478Z20 1.0uF Part No. C173 2113743M08 0.022uF...
Page 99
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C420 2113743L41 0.01uF C486 2113743L17 1000pF CR440 4813833C02 Dual Diode Common Cathode L309 2479990C02 16.28nH...
Circuit Board/Schematic Diagrams and Parts List UHF Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola Description C172 2113740F51 100pF C265 Not Placed C330 2113743N26 10pF Part No. C173 2113743M08 0.022uF...
Page 111
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C397 2311049A05 0.47uF C472 2113743N50 100pF CR203 4862824C03 Varactor L242 2462587V38 220nH C400 2113743L41 0.01uF...
Page 112
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. Q419 5180159R01 Dual NPN Transistor R256 0662057M37 R351 0662057C01 R478 0662057M98 Q420 4805128M67 PNP Transistor...
Circuit Board/Schematic Diagrams and Parts List UHF Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola Description C172 2113740F51 100pF C265 Not Placed C330 2113743N26 10pF Part No. C173 2113743M08 0.022uF...
Page 124
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C397 2311049A05 0.47uF C472 2113743N50 100pF CR203 4862824C03 Varactor L243 2460593C01 Teflon Resonator, Rx...
Page 125
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. Q420 4805128M67 PNP Transistor R260 0662057M74 R352 0662057M86 3.3K R481 0662057N08 Q421 4880214G02 NPN Transistor...
Troubleshooting charts 9A-51 10.0 Troubleshooting charts 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, Audio PA J402 Audio and RF IC select (U420) input...
9A-52 Troubleshooting charts START Bad SINAD Bad 20dB Quieting No Recovered Audio Audio at pin Check Controller 27 of U301? Spray of inject 1st IF into XTAL Filter IF Freq: 45.1MHz Check Q320 bias circuitry for faults. Audio heard? Rotate Freq. Knob Check 2nd LO Control Voltage at C363 Activity...
Troubleshooting charts 9A-53 Inject RF into J101 Trace IF signal Q302 collec- from L311 to IF Signal at tor OK? Q302. Check for L311? IF signal bad XTAL filter. present? Before replacing U301, check U301 voltages; 1st LO O/P trace IF signal RF Signal at Check FGU path.
9A-54 Troubleshooting charts START No Power Is There B+ Bias for Check Q111 Ant switch CR101 Is Control Voltage Check PCIC Is Current High or Low at C119 High Check Drive to Module 1. Check Pin Diodes 2. Check Harmonic Filter Is Drive Troubleshoot Inspect/Repair Tx.
Transmitter 9B-3 Transmitter P C I C Antenna Vcontrol Vcontrol Jack Antenna Switch/ From VCO PA-Final Harmonic Filter/ Driver Stage Matching Network Figure 9-1 Transmitter Block Diagram General (Refer to Figure 9-1) The VHF transmitter contains five basic circuits: 1. power amplifier 2.
Page 136
9B-4 Transmitter 3.1.2 Antenna Switch The antenna switch circuit consists of two PIN diodes (D3521 and D3551), a pi network (C3531, L3551 and C3550), and two current limiting resistors (R3571, R3572, R3573 ). In the transmit mode, B+ at PCIC (U3502) pin 23 will go low and turn on Q3561 where a B+ bias is applied to the antenna switch circuit to bias the diodes "on".
Receiver 9B-5 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 U3220 RSSI Synthesizer 16.8 MHz Reference Clock SPI Bus Second...
9B-6 Receiver The output of the post-RF amplifier filter is connected to the passive double balanced mixer which consists of T3301, T3302 and CR3301. Matching of the filter to the mixer is provided by C3317, C3318 and L3308. After mixing with the first LO signal from the voltage controlled oscillator (VCO) using high side injection, the RF signal is down-converted to the 45.1 MHz IF signal.
Receiver 9B-7 Automatic Gain Control Circuit (Refer to VHF Receiver Front End Schematic Diagram on page 9B-16 and VHF Receiver Back End Schematic Diagram on page 9B-17) The front end automatic gain control circuit provides automatic reduction of gain, of the front end RF amplifier via feedback.
9B-8 Frequency Generation Circuitry Frequency Generation Circuitry Voltage Multiplier Rx Out Mixer Aux3 VCOBIC Rx VCO Circuit Vmult1 U3801 Synthesizer Vmult2 U3701 Loop Filter Tx Out PA Driver 16.8 MHz Ref. Osc. Tx VCO Circuit MOD Out Modulating Signal Figure 9-3 Frequency Generation Unit Block Diagram The Frequency Generation Circuitry is composed of two main ICs, the Fractional-N synthesizer (U3701), and the VCO/Buffer IC (U3801).
Frequency Generation Circuitry 9B-9 Synthesizer (Refer toVHF Synthesizer Schematic Diagram on page 9B-18) The Fractional-N Synthesizer uses a 16.8MHz crystal (Y3761) to provide a reference for the system. The LVFractN IC (U3701) further divides this to 2.1MHz, 2.225MHz, and 2.4MHz as reference frequencies.
9B-10 Frequency Generation Circuitry VCO - Voltage Controlled Oscillator (Refer toVHF Voltage Controlled Oscillator Schematic Diagram on page 9B-19) AUX3 (U3701 Pin2) U3701 Pin 32 Prescaler Out TRB_IN Pin 20 Pin 19 Pin 12 Pin7 Rx-SW TX/RX/BS Pin13 Tx-SW Switching Network LO RF INJECTION Presc Vcc-Superfilter...
Page 143
Frequency Generation Circuitry 9B-11 The RF section of the VCOBIC(U3801) is operated at 4.54 V (VSF), while the control section of the VCOBIC and Fractional-N synthesizer (U3701) is operated at 3.3V. The operation logic is shown in Table 9-1. Table 9-1 VCO Control Logic Desired AUX 4 AUX 3...
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 multime- ter or equivalent. Transmitter measurements should be made with a 1.2 µH choke in series with the voltage probe to prevent circuit loading.
Circuit Board/Schematic Diagrams and Parts List VHF Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola C3280 2113743L39 8200pF C3524 2113740F34 22pF C3727 2113743N50 100pF Description Part No. C3301...
Page 154
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C408 2113743N50 100pF C484 2113743L17 1000pF D3832 4862824C01 Varactor L3823 2462587N49 47nH C409 2113743M24 0.1uF, +80%/-20%...
Circuit Board/Schematic Diagrams and Parts List VHF Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola C3275 2113743N44 56pF C3509 2113743L05 330pF C3709 2113743M24 100000pF, +80%/-20% Description Part No.
Page 165
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C3824 2113743N44 56pF C452 2113743G26 4.7uF, +80%/-20% C520 2113743L17 1000pF L3271 2462587Q20 2.2uH C3825...
Page 166
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. PB504 4080523Z01 Tactile Push Button R3270 0662057M74 1000 R3565 Not Placed R400 0662057N15 Q3200...
Page 167
Barcode Label SH3201 2602023X08 Rx Back end top shield 8480675Z03 VHF main PC board SH3202 2686081B02 LVZIF Shield * Motorola Depot Servicing only SH3203 2686081B03 45.1MHz Xtal Shield SH3301 2686081B01 Rx Back end bottom shield SH3302 2686081B05 Mixer Shield SH3303 2686081B06...
Circuit Board/Schematic Diagrams and Parts List VHF Radio Parts List Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Part No. Part No. Part No. Circuit Motorola C3275 2113743N44 56pF C3509 2113743L05 330pF C3709 2113743M24 100000pF, +80%/-20% Description Part No.
Page 177
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. C3824 2113743N44 56pF C452 2113743G26 4.7uF, +80%/-20% C520 2113743L17 1000pF L3301 2462587T35 12nH C3825...
Page 178
Circuit Board/Schematic Diagrams and Parts List Circuit Motorola Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Description Part No. Part No. Part No. Part No. Q3200 4813827A07 NPN Transistor R3271 0662057M42 R3569 Not Placed R401 0662057M01 Q3201 4880214G02 NPN Transistor...
Page 179
Barcode Label SH3201 2602023X08 Rx Back end top shield 8480675Z04 VHF main PC Board SH3202 2686081B02 LVZIF Shield * Motorola Depot Servicing only SH3203 2686081B03 45.1MHz Xtal Shield SH3301 2686081B01 Rx Back end bottom shield SH3302 2686081B05 Mixer Shield SH3303 2686081B06...
Page 180
Circuit Board/Schematic Diagrams and Parts List THIS PAGE INTENTIONALLY LEFT BLANK...
Troubleshooting Charts 9B-49 10.0 Troubleshooting Charts MCU Check Press PTT. Red LED does not Before replacing light up Power Up Not able to pro- MCU, check SPI Alert Tone Audio gram RF Board AUDIO clock, SPI data, at AudioPA J402 Audio and RF IC select (U420) input at Pin 3 &...
9B-50 Troubleshooting Charts START Bad SINAD Bad 20dB Quieting No Recovered Audio Audio at pin Check Controller 27 of U3220? Spray of inject 1st IF into XTAL Filter IF Freq: 45.1MHz Check Q3270 bias circuitry for faults. Audio heard? Rotate Freq. Knob Check 2nd LO Control Voltage at C3279 Activity...
Troubleshooting Charts 9B-51 Inject RF into J3501 Trace IF signal Q3200 collec- from C3200 to IF Signal at tor OK? Q3200. Check for C3200? IF signal bad XTAL filter. present? Before replacing U3220, check U3220 volt- 1st LO O/P ages; trace IF RF Signal at Check FGU signal path.
9B-52 Troubleshooting Charts START No Power Is There B+ Bias for Check Ant switch Q3561 D3521 Control Voltage High or Is Current Check PCIC Low at TP3502 High Check Drive to Module 1. Check Pin Diodes 2. Check Harmonic Filter Is Drive Troubleshoot Inspect/Repair Tx.
Troubleshooting Charts 9B-53 Check U3201, 3.3V at U3701 Start L3731 pins 5, 20, 34 & Visual Check D3701, D3702, Correct check of the U3701, C3701 - Problem Board OK? C3707 Is 16.8MHz 16.8MHz Replace at pin 6 of Is U3701 Pin 47 Signal at signal at U3701...
10-1 Section 10 FLEX LAYOUT/SCHEMATIC DIAGRAMS AND PARTS LISTS Keypad-Controller Interconnect Flex <- TO KP Front Metal View From Top Side 8480475Z02 REV A TO CTRL -> J601 J400 ZMY0130344-O Schematic for Keypad-Controller Interconnect Flex CONTROLLER KEYPAD J601 J400 FLAT_RX_SND FLAT_RX_SND RX_AUD_RTN RX_AUD_RTN...
Schematic For Speaker/Mic Assembly - 0104008J99 J402 M401 4 PIN CONN C800 INT_MIC 100pF INT_SPN M400 SPKR_20 SPKR_20 ZMY0130346-O Parts List for Speaker/Mic Assembly - 0104008J99 Reference Motorola Description Symbol Part No. C800 2113740A55 Cap, 100pF M400 5085738Z02 Speaker M401 5013920A04 Mic, Mini electrec 8485687Z01...
Page 189
Micro Controller Unit MRTI Motorola Radio-Telephone Interconnect: a system that provides a repeater connection to the Public Switched Telephone Network (PSTN). The MRTI al- lows the radio to access the telephone network when the proper access code is received.
Page 190
Term Definition Private-Line® tone squelch: a continuous sub-audible tone that is transmitted along with the carrier. Phase-Locked Loop: a circuit in which an oscillator is kept in phase with a ref- erence, usually after passing through a frequency divider. Push-To-Talk: the switch located on the left side of the radio which, when pressed, causes the radio to transmit.
Page 191
Service Manuals need to be updated accordingly. If you wish to be informed of these updates, kindly fill in and fax us your details. Fax to: 6-04-6124944 The Technical Publications Coordinator, Media and Communications, R&D Department, Motorola Penang. Your Details Name/Contact Person: Company Name: Address: Telephone No.: Fax No.:...
Page 192
Kindly take a few moments to provide feedback on this manual. Thank you for your cooperation. Fax to: 6-04-6124944 The Technical Publications Coordinator, Media and Communications, R&D Department, Motorola Penang. 1. Please check all the appropriate boxes: Disassembly Pro- cedures Alignment...