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GM1200E Mobile Radio Detailed Service Manual 68P64115B15 European Publications Department (RPG) Fleet, Hampshire, England Issue: July 1998...
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Cautions and Warnings CAUTION ELECTROSTATIC SENSITIVE DEVICES PRECAUTIONS SHOULD BE TAKEN TO MINIMIZE THE RISK OF DAMAGE BY ELECTROSTATIC DISCHARGE TO ELECTROSTATIC SENSITIVE DEVICES (ESDs). ANY DEVICES EMPLOYING METAL OXIDE SILICON (MOS) TECHNOLOGY ARE PARTICULARLY SUSCEPTIBLE. CIRCUIT DIAGRAMS MARKED WITH THE ABOVE SYMBOL INDICATE ELECTRONIC CIRCUITS (PECs) FOR WHICH ESD HANDLING PRECAUTIONS ARE NECESSARY.
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Cautions and Warnings WARNING SAFETY WARNINGS THE ELECTRICAL POWER USED IN THIS EQUIPMENT IS AT A VOLTAGE HIGH ENOUGH TO ENDANGER LIFE. BEFORE CARRYING OUT MAINTENANCE OR REPAIR, PERSONS CONCERNED MUST ENSURE THAT THIS EQUIPMENT IS ISOLATED FROM THE ELECTRICAL SUPPLY AND TESTS ARE MADE TO ENSURE THAT ISOLATION IS COMPLETE.
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Contents Detailed Service Manual Contents Chapter Introduction Gives a brief introduction into the manual and the service policy. Control Head - Level 3 Information Provides level 3 service information on the Display/Keypad Control Head (K6) detailed in the following chapters: Introduction/Theory of Operation PCB/Schematic Diagrams and Parts Lists UHF/VHF Radio - Level 3 Information...
Table of Contents Chapter 1 Introduction Table of Contents Paragraph Page Introduction ....................1 Scope of Manual ..................1 How to Use This Manual ................1 Warranty and Service Support ..............1 Warranty Period................... 1 After Warranty Period .................. 2 Piece Parts ....................
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. To ensure the product has been correctly programmed or has not been subjected to damage outside the terms of the warranty.
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Some replacement parts, spare parts, and/or product information can be ordered directly. If a complete Motorola part number is assigned to the part, it is available from Motorola Radio Parts and Service Group (RPSG). If a generic part is listed or only a part description is listed, the part is not normally available from Motorola.
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Table of Contents Chapter 2 Control Head - Level 3 Information Table of Contents Chapter Introduction/Theory of Operation PCB/Schematic Diagram and Parts List Control Head - Level 3 Information...
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Table of Contents 2-ii Control Head - Level 3 Information...
Table of Contents Chapter 2.1 Introduction/Theory of Operation Table of Contents Paragraph Page Overview ..................... 1 Exploded View Diagram ................2 Theory of Operation .................. 2 General ......................2 Power Supplies.................... 3 Voltage Regulator Circuit................3 Power On / Off ..................... 3 Microprocessor Circuit .................
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Table of Contents 2.1-ii Introduction/Theory of Operation...
Overview Overview 128 Channel, Keypad/Display Radio Control Head (Model K6) MENU The features of the radio control head are as follows: On/Off Button Rocker type Volume Up/Down Control Volume Level Indicators (RSSI) Backlit Liquid Crystal Display (LCD) with display icons to show call progress and status Up/Down scrolling keys for the display Left/Right scrolling keys for the display 3 x 4 CCITT Keypad...
- numerical information e.g. channel number, select code, call address name. To control the LEDs and the LCD, and to communicate with the host radio, the control head uses the Motorola 68HC11E9 or 68HC11E20 (dependent on the used character set) microprocessor.
Theory of Operation Power Supplies The power supply to the control head is taken from the host radio FLT A+ voltage via connector J0901 pin 2. The voltage FLT A+ is at battery level and is used for the LEDs, the back light, to power up the radio via On / Off button and to supply the voltage regulator circuit.
Theory of Operation Microprocessor Circuit The control head uses the Motorola 68HC11E9 or 68HC11E20 (dependent on the used character set) microprocessor ( µ P) (U0901) to control the LEDs, the LCD and to communicate with the host radio. RAM and ROM are contained within the microprocessor itself.
Theory of Operation When the host radio needs to communicate to the control head µ P it brings the control head select line (CNTL HD CE) to a logic ‘0’ and then sends the proper data and clock signals. After the data has been sent the control head select line is returned to a logic ‘1’.
Theory of Operation The display driver is fixed on the flex which connects the display to the PC board. The driver contains a data interface to the µ P, an LCD segment driver, an LCD power circuit, an oscillator, data RAM and control logic.
Table of Contents Chapter 2.2 PCB/Schematic Diagram and Parts List Table of Contents Description Page Display/Keypad Radio Control Head (K6) - Diagrams and Parts Lists PCB Layout Top Side ........... . 1 PCB Layout Bottom Side .
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Table of Contents 2.2-ii PCB/Schematic Diagram and Parts List...
Table of Contents Chapter 3 UHF/VHF Radio - Level 3 Information Table of Contents Chapter Introduction/Theory of Operation PCB/Schematic Diagrams and Parts Lists UHF/VHF Radio - Level 3 Information...
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Table of Contents 3-ii UHF/VHF Radio - Level 3 Information...
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Table of Contents Chapter 3.1 Introduction/Theory of Operation Table of Contents Paragraph Page Introduction ....................1 Open Controller ..................1 General ......................1 Voltage Regulators ..................1 Electronic On/Off ..................2 Emergency....................2 Mechanical On/Off ..................3 Ignition ......................3 Hook RSS ....................
It consists of a microprocessor, support memory, support logic, signal MUX ICs, the On/Off circuit, and general purpose Input/Output circuitry. The controller uses the Motorola 68HC11K1 microprocessor (U0101). In addition to the microprocessor, the controller has 3 external memory devices. The 3 memory devices consist of a 32kbyte SRAM (U0103), a 512kbyte FLASH EEPROM (U0102), and a 16kbyte EEPROM (U0104).
Open Controller Regulator U0601 is used to generate the 9.3 volts required by some audio circuits, the RF circuitry and power control circuitry. Input and output capacitors (C0601-C0603 and C0604/C0605) are used to reduce high frequency noise. R0602/R0603 set the output voltage of the regulator. If the voltage at pin 1 is greater than 1.3 volts the regulator output decreases and if the voltage is less than 1.3 volts the regulator output increases.
Open Controller While EMERGENCY CONTROL is low, SW B+ is on, the microprocessor starts execution, reads that the emergency input is active through the voltage level of EMER IGN SENSE, and sets the B+ CONTROL output of the ASFIC pin B4 to a logic high. This high will keep Q0611 switched on. This operation allows a momentary press of the emergency switch to power up the radio.
Open Controller Microprocessor Clock Synthesizer The clock source for the microprocessor system is generated by the ASFIC (U0201). Upon power- up the synthesizer U5701 (UHF) / U3701 (VHF) / U2701 (MB) generates a 2.1 MHz waveform that is routed from the RF section (via C0202) to the ASFIC (on U0201-E1) For the main board controller the ASFIC uses 2.1MHz as a reference input clock signal for its internal synthesizer.
Open Controller When the control head with graphical display wants to communicate to the µ P it brings request line ANALOG 2 (J0101-11) to a logic “0“. The µ P reads this line via one of the analogue to digital converters (U0101-48) and then starts communication by activating the control head select line (LED CHT CE) via U0105-9 and J0101-12, sending the clock signal via U0106-3 and J0101-5 and sending data via U0106-2 and J0101-6 or receiving data via J0101-10 and gate U0171.
Open Controller 2.11 General Purpose Input/Output The Controller provides one general purpose line (GP I/O) available on the accessory connector J0400-12 to interface to external options. The software and the hardware configuration of the radio model defines the function of the port. The port uses an output transistor (Q0432) controlled by µ P via ASFIC port GCB3 (pin B3).
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Open Controller Specifically, the logic high levels should be between 4.8 and 5.0 V, and the logic low levels should be between 0 and 0.2 V. No other intermediate levels should be observed, and the rise and fall times should be <30 ns. The low-order address lines (A0-A7) and the data lines (D0-D7) should be toggling at a high rate, i.e., you should set your oscilloscope sweep to 1 us/div.
Open Controller 2.13 FLASH Electronically Erasable Programmable Memory (FLASH EEPROM) The 512 KByte FLASH EEPROM (U0102) contains the radio operating software. This software is common to all open architecture radios within a given model type. This is, as opposed to the codeplug information stored in EEPROM (U0104) which could be different from one user to another in the same company.
General 2.15 Static Random Access Memory (SRAM) The SRAM (U0103) contains temporary radio calculations or parameters that can change very frequently, and which are generated and stored by the software during its normal operation. The information is lost when the radio is turned off. The device allows an unlimited number of write cycles.
Transmit Audio Circuits Transmit Audio Circuits Refer to Figure 3-1 for reference for the following sections. Mic Input Path The radio supports two distinct microphone paths known as internal (from Control Head) and external mic (from accessory connector J0400-2) and an auxiliary path (FLAT TX AUDIO). The microphones used for the radio require a DC biasing voltage provided by a resistive network.
Transmit Audio Circuits External Mic Path The external microphone signal enters the radio on accessory connector J0400 pin 2 and connects to the standard microphone input through R0413. Components R0414 - R0416, C0413, C0414, C0417 are not used. PTT Sensing and TX Audio Processing Mic PTT coming from the Control Head via connector J101-4 is sensed by the µP U0101 pin 22.
Transmit Signalling Circuits Transmit Signalling Circuits Refer to Figure 3-2 for reference for the following sections. From a hardware point of view, there are three types of signalling: Sub-audible data (PL/DPL/Connect Tone) that gets summed with transmit voice or signalling, DTMF data for telephone communication in trunked and conventional systems, and Audible signalling including Select 5, MPT-1327, MDC, High speed Trunking.
Transmit Signalling Circuits High Speed Data High speed data refers to the 3600 baud data waveforms, known as Inbound Signalling Words (ISWs) used in a trunking system for high speed communication between the central controller and the radio. To generate an ISW, the µP first programs the ASFIC (U0201) to the proper filter and gain settings.
Receive Audio Circuits CH ACT is routed to the µP pin 40 while SQ DET adds up with LOCK DET, weighted by resistors R0113, R0114, and is routed to one of the µP´s ADC inputs U0101-43. From the voltage weighted by the resistors the µP determines whether SQ DET, LOCK DET or both are active.
Receive Audio Circuits The audio PA is enabled via AUDIO PA ENABLE signal from the ASFIC (U0201-B5). When the base of Q0401 is low, the transistor is off and U0401-8 is high, using pull up resistor R0406, and the Audio PA is ON.
Receive Signalling Circuits Receive Signalling Circuits Refer to Figure 3-4 for reference for the following sections. LOW SPEED HIGH SPEED CLOCK CLOCK DATA FILTER LIMITER AND DEEMPHASIS MICRO CONTROLLER ASFIC DET AUDIO U0201 U0101 DISCRIMINATOR AUDIO FROM RF SECTION (IF IC) FILTER LIMITER LOW SPEED...
Receiver Front-End The allowable internal alert tones are 304, 608, 911, and 1823Hz. In this case a code contained within the SPI BUS load to the ASFIC sets up the path and determines the tone frequency, and at what volume level to generate the tone. (It does not have to be related to the voice volume setting). For external alert tones, the µP can generate any tone within the 100-3000Hz audio band.
Transmitter Power Amplifier (PA) 5-25W Mixer and Intermediate Frequency (IF) Section The signal coming from the front-end is converted to the first IF (45.1 MHz) using a double balanced schottky diode mixer (D5401). Its ports are matched for incoming RF signal conversion to the 45.1MHz IF using low side injection.
Transmitter Power Amplifier (PA) 5-25W The collector current of Q5510 causes a voltage drop across the resistors R5623 and R5624. Transistor Q5612 adjusts the voltage drop across R5621 controlled through the PA control line (PWR CNTL). The current source Q5621 adjusts the collector current of Q5510 by modifying its base voltage via (R5502, L5501) until the voltage drop across R5623 and R5624 plus V (0.6V) equals the voltage drop across R5621 plus V...
Transmitter Power Amplifier (PA) 5-25W Antenna Switch The antenna switch is switched synchronously with the K9V1 voltage and feeds either the antenna signal coming through the harmonic filter to the receiver or the transmitter signal coming from the PA to the antenna via the harmonic filter. In transmit mode, this K9V1 voltage is high and biases Q5520 and along with the RF signal from Q5510 allows a collector current to be drawn.
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Transmitter Power Amplifier (PA) 5-25W The ALC loop regulates power by adjusting the PA control line PWR CNTL to keep the forward power voltage PWR DETECT at a constant level. Opamp U0701-2 and resistors R0701 to R0703 and R0731 subtract the negative PWR DETECT voltage from the PA PWR SET D/A output U0731 pin 2.
Frequency Synthesis 10.0 Frequency Synthesis The complete synthesizer subsystem consists of the Reference Oscillator (Y5701 or U5702), the Fractional-N synthesizer (U5701), the Voltage Controlled Oscillator (Q5741), the RX and TX buffer stages (Q5751, Q5771, Q5781) and the feedback amplifier (Q5791). 10.1 Reference Oscillator The Reference Oscillator (Y5702) contains a temperature compensated crystal oscillator with a...
Frequency Synthesis 10.3 Voltage Controlled Oscillator (VCO) The Voltage Controlled Oscillator (VCO) is formed by the colpitts oscillator FET Q5741. Q5741 draws a drain current of 12 mA from the FRAC-N IC super filter output. The oscillator frequency is half of the desired frequency and mainly determined by L5743, C5742, C5743, C5745 - C5748 and varactor diodes D5741 / D5742.
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Receiver Front-End To reduce synthesizer lock time when new frequency data has been loaded into the synthesizer the magnitude of the loop current is increased by enabling the IADAPT line (U5701-31) for a certain software programmable time (Adapt Mode). The adapt mode timer is started by a low to high transient of the FRACN CE line.
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Transmitter Power Amplifier (PA) 5-25W A second two pole varactor tuned bandpass filter provides additional filtering to the amplified signal. The dual varactor diode D3304 is controlled by the same signal which controls the pre-selector filter. If the radio is configured for a base station application, R3318 is not placed and TP3301 and TP3302 are shorted.
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Transmitter Power Amplifier (PA) 5-25W 12.1 Power Controlled Stage The first stage (Q3511) amplifies the RF signal from the VCO (line EXCITER PA) and controls the output power of the PA. The output power of the transistor Q3511 is proportional to its collector current which is adjusted by a voltage controlled current source consisting of Q3641, (Q3643-T3 only) and Q3642.
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Transmitter Power Amplifier (PA) 5-25W 12.4 Antenna Switch The antenna switch is switched synchronously with the K9V1 voltage along with the voltage PWR CNTL signal and feeds either the antenna signal coming through the harmonic filter to the receiver or the transmitter signal coming from the PA to the antenna via the harmonic filter. In transmit mode, this PWR CNTL is above 1 V and biases Q3511 through Q3641 and Q3642 to allow a collector current to be drawn.
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Transmitter Power Amplifier (PA) 5-25W The ALC loop regulates power by adjusting the PA control line PWR CNTL to keep the forward power voltage PWR DETECT at a constant level. Opamp U0701-2 and resistors R0701 to R0703 and R0731 subtract the negative PWR DETECT voltage from the PA PWR SET D/A output U0731 pin 2.
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Frequency Synthesis 13.0 Frequency Synthesis The complete synthesizer subsystem consists of the Reference Oscillator (Y3701 or Y3702), the Fractional-N synthesizer (U3701), the Voltage Controlled Oscillator (Q3741, Q3751), the RX and TX buffer stages (Q3760, Q3770, Q3780) and the feedback amplifier (Q3790). 13.1 Reference Oscillator The Reference Oscillator (Y3702) contains a temperature compensated crystal oscillator with a...
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Frequency Synthesis In TX mode AUX3 is about 5V DC and Q3742 is switched off. Q3752 is switched on and enables a current flow from the source of FET Q3741 while Q3751 is switched off. When switched on the FETs draw a drain current of 8 mA from the FRAC-N IC super filter output.
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Frequency Synthesis LOCK DET adds up with signal SQ DET, weighted by resistors R0113, R0114, and is routed to one of the µP´s ADCs input U0101-43. From the voltage weighted by the resistors the µP determines whether SQ DET, LOCK DET or both are active. In order to modulate the PLL the two spot modulation method is utilized.
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Table of Contents Chapter 3.2 PCB/Schematic Diagrams and Parts Lists Table of Contents Description Page PCB Overlays UHF (403-430MHz)PCB 8486072B01_T1 Layout Top Side ............1 Layout Bottom Side .
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Table of Contents Description Page RX-FE Schematic Diagram ..........21 Parts List.
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R0853 R0944 C0895 VR0902 R0941 R0855 TP0951 R0942 C0928 R0891 R0927 C0955 MOTOROLA 1998 8486015B05-T3 VR0904 VR0903 VR0906 Q0891 D0891 Bottom Side S ld 8486015B05 T3 GEPD5549 3 Display/Keypad Radio Control Head (K6) PCB No. 8486015B05_T3 PCB/Schematic Diagram and Parts List...
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Display/Keypad Radio Control Head Schematic Diagram Display/Keypad Radio Control Head Circuit Motorola Circuit Motorola Circuit Motorola Parts List Description Description Description Part No. Part No. Part No. D0851- 4805729G75 LED GREEN HP R0851 0662057A73 10k 1/16W 5% R0924 0662057A89 47k 1/16W 5%...
Controller Schematic Diagram Controller Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Parts List Part No. Part No. Part No. C0158 2113741F17 CAP CHIP 470pF 50V C0234 2113743E20 CAP CHIP 100nF 16V D0101 4813833C02 DUAL SOT MMBD6100 Circuit Motorola Description Part No.
UHF (403-470MHz) Power Control Schematic Diagram Power Control Circuit Motorola Description Parts List Part No. R0715 0662057A81 22k 1/16W 5% Circuit Motorola Description Part No. R0716 0662057B16 560k 1/16W 5% R0717 0662057A85 33k 1/16W 5% C0701 2113740F51 100pF 5% 50V...
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UHF (403-470MHz) Power Amplifier 5-25W Schematic Diagram Power Amplifier 5-25W Circuit Motorola Circuit Motorola Circuit Motorola Description Description Description Parts List Part No. Part No. Part No. C5602 2113740F51 100pF 5% 50V L5600 2484657R01 Ferrite Bead R5617 0680194M01 10 1W 5%...
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UHF (403-470MHz) Synthesizer Schematic Diagram Not Used UHF (403-470MHz) Synthesizer Schematic Diagram PCB/Schematic Diagrams and Parts Lists 3.2-17...