Kenwood-NXR-710-Service-Manual电路原理图.pdf

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1、SERVICE MANUALThis product uses Lead Free solder.This product complies with the RoHS directive for the European market. 2009-12 PRINTED IN JA PANB51-8901-00 (N) 527NXR-710VHF DIGITAL BASE-REPEATERCH/STATUSVOLUMEBUSYTXPOWERMICFUSEN SYNCDC 13.6VREF IN RX INTX OUT CONTROLI/OTEST/SPKRFront panel(A62-117

2、4-03)Knob (Power)(K29-9106-04)Key top(K29-9370-02)Knob (Volume)(K29-5389-03)Modular jack(E58-0522-05)Rear panel(A82-0077-02)Antenna cable (REF IN)(E30-7690-05)Antenna cable (RX IN)(E30-3418-15)Lead wire with connector (ACC15P)(E37-0913-05)Lead wire with connector(DSUB25P)(E37-1376-05)Modular jack x

3、2(E58-0533-05)DC cord (Ext DC in)(E30-3414-05)Blade fuse (15A/32V)(F05-1537-05)Antenna cable (TX OUT)(E30-7528-15)GENERAL . 2SYSTEM SET-UP . 3REALIGNMENT . 3OPERATING FEATURES . 5INSTALLATION . 6MODIFICATION . 8DISASSEMBLY FOR REPAIR . 8CIRCUIT DESCRIPTION . 9COMPONENTS DESCRIPTION . 18PARTS LIST .

4、20EXPLODED VIEW . 36PACKING . 38ADJUSTMENT . 39TERMINAL FUNCTION . 53PC BOARDFINAL UNIT (X45-3920-10) . 58CONTROL UNIT (X53-4490-10) . 62DISPLAY UNIT (X54-3580-20) . 66TX-RX UNIT (X57-7940-10) . 70RX VCO/PLL UNIT (X58-5070-10) . 74TX VCO/PLL UNIT (X58-5080-10) . 75INTERCONNECTION DIAGRAM . 76SCHEMAT

5、IC DIAGRAM . 78BLOCK DIAGRAM . 96OPTIONAL ACCESSORIESKES-5 (EXTERNAL SPEAKER) . 99SPECIFICATIONS .BACK COVERCONTENTSNXR-7102Document CopyrightsCopyright 2009 by Kenwood Corporation. All rights re-served.No part of this manual may be reproduced, translated, distributed, or transmitted in any form or

6、by any means, electronic, mechanical, photocopying, recording, or other-wise, for any purpose without the prior written permission of Kenwood.DisclaimerWhile every precaution has been taken in the preparation of this manual, Kenwood assumes no responsibility for er-rors or omissions. Neither is any

7、liability assumed for dam-ages resulting from the use of the information contained herein. Kenwood reserves the right to make changes to any products herein at any time for improvement purposes.Firmware CopyrightsThe title to and ownership of copyrights for firmware embedded in Kenwood product memor

8、ies are reserved for Kenwood Corporation. Any modifying, reverse engineer-ing, copy, reproducing or disclosing on an Internet website of the firmware is strictly prohibited without prior written consent of Kenwood Corporation. Furthermore, any resell-ing, assigning or transferring of the fi rmware i

9、s also strictly prohibited without embedding the firmware in Kenwood product memories.Transceivers containing AMBE+2 Vocoder:The AMBE+2 voice coding technology is embedded in the fi rmware under the license of Digital Voice Systems, Inc.GENERALINTRODUCTIONSCOPE OF THIS MANUALThis manual is intended

10、for use by experienced techni-cians familiar with similar types of commercial grade com-munications equipment. It contains all required service information for the equipment and is current as of the pub-lication date. Changes which may occur after publication are covered by either Service Bulletins

11、or Manual Revisions. These are issued as required.ORDERING REPLACEMENT PARTSWhen ordering replacement parts or equipment informa-tion, the full part identifi cation number should be included. This applies to all parts: components, kits, or chassis. If the part number is not known, include the chassi

12、s or kit number of which it is a part, and a suffi cient description of the re-quired component for proper identifi cation.PERSONAL SAFETYThe following precautions are recommended for personal safety: DO NOT transmit if someone is within two feet (0.6 me-ter) of the antenna. DO NOT transmit until al

13、l RF connectors are secure and any open connectors are properly terminated. SHUT OFF this equipment when near electrical blasting caps or while in an explosive atmosphere. All equipment should be properly grounded before pow-erup for safe operation. This equipment should be serviced by only qualifie

14、d technicians.SERVICEThis transceiver is designed for easy servicing. Refer to the schematic diagrams, printed circuit board views, and alignment procedures contained within.NXR-7103SYSTEM SET-UPREALIGNMENT1. ModesUser modePC modeFirmware programming modePC programming modePC test mode PC tuning mod

15、eMode FunctionUser mode Use this mode for normal operation.PC modeUse this mode to make various settings by means of the FPU through the RS-232C port.PC programming modeUse to read and write frequency data and other features to and from the repeater.PC test modeUse to check the repeater using the PC

16、. This feature is included in the FPU.Firmware program-ming modeUse when changing the fi rmware program of the fl ash memory.2. How to Enter Each ModeMode OperationUser mode Power on.PC mode Received commands from PC.Firmware programming mode PF1 + Power on (one second)3. PC Mode3-1. PrefaceThe NXR-

17、710 is programmed by using a personal com-puter, programming interface (KPG-46/46A) and program-ming software (KPG-129D).The programming software can be used with a PC. Fig-ure 1 shows the setup of a PC for programming.3-2. Connection Procedure1. Connect the NXR-710 to the computer using the inter-f

18、ace cable and USB adapter (When the interface cable is KPG-46A, the KCT-53U can be used.).Note: You must install the KCT-53U driver in the computer to use the USB adapter (KCT-53U). When using the USB adapter (KCT-53U) for the first time, plug the KCT-53U into a USB port on the computer with the com

19、puter power ON.2. When power is applied, the user mode is entered im-mediately. When the PC sends a command, the repeater enters the PC mode and displays “PC” on the 7-seg-ment LED. When data is being transmitted to the PC from the repeater, the TX LED fl ashes. The BUSY LED fl ashes when data from

20、the PC is being received by the repeater.Note: The data stored in the personal computer must match the model type, when it is written into the fl ash memory. Change the NXR-710 to PC mode, then attach the inter-face cable.Merchandise receivedChoose the type of transceiverSee page 3.A personal comput

21、er, programming interface (KPG-46/46A), and programming software (KPG-129D) are required for programming.DC power supply or duplexer?Repeater programming =CN40PSWCONTROL UNIT (X53-4490-10) Component sideNXR-71091. OutlineThe NXR-710 is a VHF repeater operating in the 136 174MHz frequency range.2. TX

22、-RX unitTX-RX unit (X57-7940-10) consists of the following cir-cuit.(1) Internal/external reference circuit (2) Transmitter reference 16.8MHz PLL circuit(3) Transmitter main PLL circuit(4) Modulation level adjustment circuit(5) Front-end circuit(6) 1st-Mixer circuit(7) IF circuit(8) Receiver PLL cir

23、cuits(9) AVR circuits(10) Other circuits2-1. Internal/External reference circuitThe internal reference circuit consists of X500, Q502, Q504 and D505. The output of 19.2MHz VCTCXO (X500) is fed to buffer amplifi er Q502. The higher harmonic wave is attenuated by the LPF. This reference signal is fed

24、to IF IC (IC304) as the 2nd Local signal through the Tripler. The internal reference signal is amplified by Q504 to achieve the needed level for PLL ICs. That signal is divided by a Wilkinson divider. The divided signal is fed to the PLL IC for the receiver. Another signal is fed to the transmitter

25、reference 16.8MHz PLL IC through PIN diode switch (D505) which switches the Internal or external reference.The external reference circuit consists of CN500, Q501, Q503, IC500, IC501, D503 and D504. The external refer-ence signal (10MHz/0dBm) input from CN500 is fed to buf-fer amplifi er Q501 and is

26、amplifi ed by Q503. Q503 is a dual gate MOS-FET. The output of amplifi er (Q503) is detected by D503 and that DC voltage is amplified by IC500 (B/2). The amplifi ed DC voltage is compared to the reference volt-age by IC500 (A/2). The difference of voltages is amplifi ed by IC500 (A/2) and is fed to

27、the gate-2 terminal of Q503. The voltage of the Q503 gate-2 terminal is controlled automati-cally to constantly maintain the power output of amplifier (Q503). The output of amplifi er (Q503) is fed to the transmit-ter reference 16.8MHz PLL IC through the PIN diode switch (D504) which switches the In

28、ternal or External reference.The PIN diode switches (D504, D505) are controlled by the I/O expander IC (IC805 Pin15). The I/O expander IC is controlled by the MCU which is in the Control unit (X53-449). If internal reference is selected by FPU, the I/O expander IC outputs an “H” status. This signal

29、sets power switch Q506 to ON. Then D505 is activated.If external reference is selected, the I/O expander IC out-puts an “L” status. This signal sets power switch Q500 to ON. Then D504 is activated.CIRCUIT DESCRIPTION10MHz or19.2MHzDetectorRX VCO/PLL1dBATT1dBATTX58-5070-102nd LoREFAMPQ504AMPQ502AGC A

30、MPQ503BufferQ501SWX3Q202LPFLPFCN500LPFD503AMPIC500(B/2)AMPIC500(A/2)X500OSC19.2MHzD504,D505EXT_IN10MHzFig. 1 Internal/external reference circuit2-2. Transmitter reference 16.8MHz PLL circuitThe transmitter reference 16.8MHz PLL circuit produces the reference frequency signal for the Transmitter Main

31、 PLL circuit and modulates the low-frequency components.The circuit consists of IC600, IC601, IC602, IC603, IC604, Q601, Q602, Q603, and X600.The VCXO (X600) signal enters the buffer amplifi er Q603 and is amplifi ed by Q602. The higher harmonic wave is at-tenuated by the LPF and returns to IC602. I

32、ts phase is com-pared with that of the reference frequency 5kHz.The phase difference signal produced by the comparing phase is converted to a DC voltage by a lag-lead type loop fi lter. This DC voltage is input to the IC604 invert amplifi er and is synthesized with the modulating signal. This DC vol

33、t-age is input to the X600 control voltage terminal for control-ling the VCXO oscillating frequency 16.8MHz.The 16.8MHz oscillating signal is fed to the Q603 buffer amplifi er. The output signal of the buffer amplifi er is used as the reference frequency signal of the transmitter main PLL circuit.NX

34、R-710102-3. Transmitter Main PLL circuit (SUB unit) VCOThe TX VCO circuit consists of two VCOs (VCO A X58-508: Q352, VCO B X58-508: Q353). Those VCOs generates a transmit carrier. VCO A Q352 produces a transmitter fre-quency from 136.000MHz to 154.995MHz. VCO B Q353 produces a transmitter frequency

35、from 155.000MHz to 174.000MHz. Those VCO oscillation frequencies are determined by two systems of voltage control terminals: “CV” and “TXAS-SIST”.The voltage control terminals, “CV” and “TXASSIST”, are controlled by the PLL IC (X58-508: IC300) and MCU (X53-449: IC20) and the output frequency changes

36、 continu-ously according to the applied voltage. For the modulation input terminal, “MO”, the output frequency changes ac-cording to the applied voltage.D355D352D358D359SW Q350TXVCOATX_CVTXASSISTTXVCOBMO80C80CVOVCO_AQ352BufferQ354SW Q351D357D353D360D361VCO_BQ353Fig. 3 Transmitter VCO circuit PLL IC

37、(X58-508: IC300)The PLL IC compares the differences in phases of the VCO oscillation frequency and the transmitter PLL reference signal (16.8MHz), returns the difference to the VCO CV ter-minal and realizes the “Phase Locked Loop” for the return control. This allows the VCO oscillation frequency to

38、accu-rately match (lock) the desired frequency. When the frequency is controlled by the PLL, the fre-quency convergence time increases as the frequency dif-ference increases when the set frequency is changed. To supplement this, the MCU is used before control by the PLL IC to bring the VCO oscillati

39、on frequency close to the desired frequency. As a result, the VCO CV voltage does not change and is always stable at approx. 3.0V.The desired frequency is set for the PLL IC by the MCU (X53-449: IC20) through the 3-line “SPSD0”, “SPSCLK0”, “/TXPCS” serial bus. Whether the PLL IC is locked or not is

40、monitored by the MCU through the “LDT” signal line. If the VCO is not the desired frequency (unlock), the “LDT” logic is low.Ref 16.8MHzLDTSPSCLK0SPSD0/TXPCSBufferQ300TX VCO/PLLIC300LPFTX_CVBPFFINLoop filterFig. 4 Transmitter Main PLL IC circuit2-4. Modulation level adjustment circuit The Modulation

41、 level adjustment circuit adjusts the mod-ulation waveform balance. This circuit consists of IC804, IC603, IC604, IC605 and IC606.The modulating signal comes from the Control unit (X53-449) through the interface connector (CN800 Pin 14). The modulating signal is produced by the modulation low-pitche

42、d tone to the transmitter modulation 16.8MHz PLL cir-cuit and adds the high-pitched modulation to the transmitter main PLL.IC804 is an electronic volume control IC. It has 8 elec-tronic volume control circuits. The modulation level adjust-ment circuit uses 2 electronic volume control circuits in IC8

43、04. The 1st electronic volume control circuit adjusts the modulating signal and is fed to IC603 and the 2nd electronic Fig. 2 Transmitter reference 16.8MHz PLL circuitTX VCO/PLLMODPLL ICX58-5080-10Ref10MHzor 19.2MHzLDTIC602SPSCLK0SPSD0/16_8PCSAMPQ602BufferQ603AMPIC604AMPIC60316.8MHzLPFLoop filterX600MBOSC16.8MHzCIRCUIT DESCRIPTION