JVC-MXKB4-cs-sm 维修电路原理图.pdf

SERVICE MANUALCOPYRIGHT 2004 VICTOR COMPANY OF JAPAN, LIMITEDNo.MB1962004/6COMPACT COMPONENT SYSTEMMB19620045MX-KB4TABLE OF CONTENTS1PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-63DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-74ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-195TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21FM MODEFM /AMAUXSLEEPSTANDBY/ONCD1CD2CD3SOUNDMODERHYTHM AXFADEMUTINGVOLUMEPROGRAM/RANDOMREPEATTAPEACDTAPEB REMOTE CONTROL CA-MXKB4SP-MXKB4SP-MXKB4Area suffixJ - U.S.A.C - CanadaRadioFans.CN 收音机爱 好者资料库1-2 (No.MB196)SPECIFICATIONDesign and specifications are subject to change without notice.AmplifierOutput Power180 W per channel, min. RMS, driven into 6 at 1kHz, with no morethan 10% total harmonic distortionInput Sensitivity/Impedance (1 kHz) AUX IN:400 mV/50 kSpeaker terminals6 - 16 Phones32 - 1 kCassette DeckFrequency Response15 mW/ch output into 32 Type I (NORMAL)63 Hz - 12 500 HzWow And Flutter0.15% (WRMS)CD PlayerCD Capacity3 CDsDynamic Range85 dBSignal-To-Noise Ratio85 dBWow And FlutterUnmeasurableTunerFM TunerTuning Range:87.5 MHz - 108.0 MHzAM TunerTuning Range:530 kHz - 1 710 kHzUnitDimensions270 mm 306 mm 456 mm (W/H/D) (10-11/16 12-1/16 18)MassApprox. 8.6 kg (19.0 lbs)Speaker SpecificationsSP-MXKB4 (each unit)Type3-way bass-reflex typeSpeaker UnitWoofer:20 cm (7-7/8) cone 1Mid:5cm (2) cone 1Tweeter:2 cm (13/16) dome 1Power Handling Capacity180 WImpedance6 Frequency Range45 Hz - 22,000 HzSound pressure level87 dB/WmDimensions257 mm 321 mm 261 mm (W/H/D) (10-1/8 12-11/16 10-5/16)MassApprox. 4.9 kg (10.9 lbs)Power SpecificationsPower RequirementsAC 120 V , 60 HzPower Consumption150 W (power on mode)22 W (in Standby mode)RadioFans.CN 收音机爱 好者资料库(No.MB196)1-3SECTION 1PRECAUTION1.1Safety Precautions(1) This design of this product contains special hardware andmany circuits and components specially for safety purpos-es. For continued protection, no changes should be madeto the original design unless authorized in writing by themanufacturer. Replacement parts must be identical tothose used in the original circuits. Services should be per-formed by qualified personnel only.(2) Alterations of the design or circuitry of the product shouldnot be made. Any design alterations of the product shouldnot be made. Any design alterations or additions will voidthe manufacturers warranty and will further relieve themanufacture of responsibility for personal injury or propertydamage resulting therefrom.(3) Many electrical and mechanical parts in the products havespecial safety-related characteristics. These characteris-tics are often not evident from visual inspection nor can theprotection afforded by them necessarily be obtained by us-ing replacement components rated for higher voltage, watt-age, etc. Replacement parts which have these specialsafety characteristics are identified in the Parts List of Ser-vice Manual. Electrical components having such featuresare identified by shading on the schematics and by ( ) onthe Parts List in the Service Manual. The use of a substitutereplacement which does not have the same safety charac-teristics as the recommended replacement parts shown inthe Parts List of Service Manual may create shock, fire, orother hazards.(4) The leads in the products are routed and dressed with ties,clamps, tubings, barriers and the like to be separated fromlive parts, high temperature parts, moving parts and/orsharp edges for the prevention of electric shock and firehazard. When service is required, the original lead routingand dress should be observed, and it should be confirmedthat they have been returned to normal, after reassem-bling.(5) Leakage shock hazard testingAfter reassembling the product, always perform an isola-tion check on the exposed metal parts of the product (an-tenna terminals, knobs, metal cabinet, screw heads,headphone jack, control shafts, etc.) to be sure the productis safe to operate without danger of electrical shock.Do notuse a line isolation transformer during this check. Plug the AC line cord directly into the AC outlet. Using aLeakage Current Tester, measure the leakage currentfrom each exposed metal parts of the cabinet, particular-ly any exposed metal part having a return path to thechassis, to a known good earth ground. Any leakage cur-rent must not exceed 0.5mA AC (r.m.s.). Alternate check methodPlug the AC line cord directly into the AC outlet. Use anAC voltmeter having, 1,000 per volt or more sensitivityin the following manner. Connect a 1,500 10W resistorparalleled by a 0.15F AC-type capacitor between an ex-posed metal part and a known good earth ground.Measure the AC voltage across the resistor with the ACvoltmeter. Move the resistor connection to each exposed metalpart, particularly any exposed metal part having a returnpath to the chassis, and measure the AC voltage acrossthe resistor. Now, reverse the plug in the AC outlet andrepeat each measurement. Voltage measured any mustnot exceed 0.75 V AC (r.m.s.). This corresponds to 0.5mA AC (r.m.s.). 1.2Warning(1) This equipment has been designed and manufactured tomeet international safety standards.(2) It is the legal responsibility of the repairer to ensure thatthese safety standards are maintained.(3) Repairs must be made in accordance with the relevantsafety standards.(4) It is essential that safety critical components are replacedby approved parts.(5) If mains voltage selector is provided, check setting for localvoltage.1.3CautionBurrs formed during molding may be left over on some partsof the chassis. Therefore, pay attention to such burrs in the case of pre-forming repair of this system.1.4Critical parts for safetyIn regard with component parts appearing on the silk-screenprinted side (parts side) of the PWB diagrams, the parts that areprinted over with black such as the resistor ( ), diode ( )and ICP ( ) or identified by the mark nearby are criticalfor safety. When replacing them, be sure to use the parts of thesame type and rating as specified by the manufacturer. (This regulation dose not Except the J and C version)Good earth groundPlace this probe on each exposedmetal part.AC VOLTMETER(Having 1000 ohms/volts,or more sensitivity)1500 10W0.15 F AC TYPE1-4 (No.MB196)1.5Preventing static electricityElectrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laserdiode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.1.5.1 Grounding to prevent damage by static electricityStatic electricity in the work area can destroy the optical pickup (laser diode) in devices such as laser products. Be careful to use proper grounding in the area where repairs are being performed. (1) Ground the workbenchGround the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing thetraverse unit (optical pickup) on it.(2) Ground yourselfUse an anti-static wrist strap to release any static electricity built up in your body. (3) Handling the optical pickup In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement opticalpickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.) Do not use a tester to check the condition of the laser diode in the optical pickup. The testers internal power source can easilydestroy the laser diode. 1.6Handling the traverse unit (optical pickup)(1) Do not subject the traverse unit (optical pickup) to strong shocks, as it is a sensitive, complex unit. (2) Cut off the shorted part of the flexible cable using nippers, etc. after replacing the optical pickup. For specific details, refer to thereplacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long atime when attaching it to the connector. (3) Handle the flexible cable carefully as it may break when subjected to strong force. (4) I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.1.7Attention when traverse unit is decomposed*Please refer to Disassembly method in the text for the pickup unit. Apply solder to the short land sections before the flexible wire is disconnected from the connecto on the servo board. (If the flexiblewire is disconnected without applying solder, the pickup may be destroyed by static electricity.) In the assembly, be sure to remove solder from the short land sections after connecting the flexible wire.1MConductive material(conductive sheet) or iron palate(caption)Anti-static wrist strapCD changer unitSolderingFlexible cable(No.MB196)1-51.8Importance administering point on the safetyCaution: For continued protection against risk offire, replace only with same type 3.5A/125V for F901 and 1.6A/250V for F902.This symbol specifies type of fast operating fuse.Precaution: Pour eviter risques de feux, remplacezle fusible de surete de F901 comme le meme typeque 3.5A/125V et 1.6A/250V pour F902.Ce sont des fusibles suretes qui functionnes rapide.1-6 (No.MB196)SECTION 2SPECIFIC SERVICE INSTRUCTIONSThis service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.(No.MB196)1-7SECTION 3DISASSEMBLY3.1Disassembly of the main blocks of the setReplacement of the fuses and the power IC3.1.1Replacing the fuses (See Fig.1) Prior to performing the following procedure, remove the leftside board.(1) Replace the fuses inside.Caution:Be sure to use fuses with the specified ratings.Fig.13.1.2Replacing the power IC (See Fig.2) Prior to performing the following procedure, remove the topcover.(1) Remove the two screws A from the heat sink between thepower IC.(2) Remove the solder fixing the power IC.Fig.23.1.3Replacing the heat sink cover (See Fig.3)(1) Remove four screws B from the rear panel.(2) Pull the heat sink cover outward.Fig.3Fuse (F901)3.5A 125VFuse (F902)1.6A 250VWAB1-8 (No.MB196)3.1.4Removing the top cover (See Fig.4 and 5)(1) Remove six screws C that retain the top cover from thepanel rear of the body.(2) Remove six screws D that retain the top cover from the twosides of the body.(3) Remove the top cover from the body by lifting it toward therear.Fig.4Fig.5Top coverCCCRight Front panel assemblyDDLeft Front panel assemblyDD(No.MB196)1-93.1.5Removing the CD changer unit (See Fig.6 to 9) Prior to performing the following procedures, remove the topcover.Caution:Although the CD mechanism unit can be removed without re-moving the CD tray panel, it is still recommended to remove itin order to prevent damage.a. From the front panel side of this set, push in the sectionsmarked with arrows and pull out the CD tray toward thefront.b. Remove the CD tray panel by pushing both of its extremi-ties upward in the direction of the arrows.c. Push the CD tray deep into the set. (1) Disconnect the cord wires from the CD board CN703 andCN203.(2) From the rear of the set, remove two screws E, two screwsF and four screws G on the front panel left and right side.(3) Handle the CD changer unit rear, take out the unit.Fig.6Fig.7Fig.8Fig.9CD tray panelCD tray panelFAntennaterminalEG1-10 (No.MB196)3.1.6Removing the front panel assembly (See Fig.10 to 11) Prior to performing the following procedures, remove the topcover. Also remove the CD changer unit.(1) Disconnect the parallel wire and the cord wire from the con-nectors CN701, CN101 on the power amp. PCB.(2) Remove one screws H retaining the front panel assemblyonto the bottom of the body.(3) Remove two screws I on the left and right side of the set re-taining the panel front from the bottom and then removethen GND lug b that comes from the amp and supplyboard.(4) Disengage the claws c on both sides of the front panel as-sembly and then remove the assembly.Fig.10Fig.11HClawGND lugGND lugabc(No.MB196)1-113.2Disassembly of units and assembly inside this set3.2.1Removing the Main board (See Fig.12 to 13) Prior to performing the following procedures, remove the topcover. Also remove the CD changer unit.(1) Disconnect the wires from CN603A, CN603B and CN604on the Main board, which is located on the back side of theCD changer unit.(2) The four screws J that retain the CD board should be re-moved.(3) Remove the CD board by pulling it toward the side wherethe CN601 is located.(4) Using solder, short the CD pickup to connect to shortround.Caution:After re-connecting the wires, be sure to remove theshorting solder from the GND connection.(5) Disconnect the card wire from the connector CN601 on theMain board and then remove the Main board.Fig.12Fig.13JPAIN PCBJJCD PCBShort round CN6011-12 (No.MB196)3.2.2Removing the CD changer mechanism assembly (See Fig.14 to 15) Also remove the CD changer unit.(1) Turn the CD changer mechanism cover base and removethe screws d connecting the unit to the CD changer mech-anism assembly.(2) Removing four screws e retaining the CD mechanism hold-er assembly.Caution:When replacing the CD changer mechanism assembly, besure not to mistake the positions of the silver color and coppercolor spring.Fig.14Fig.15 dCD changerunite ( Green color )e ( Red color )e ( Green color )e ( Red color )CD changermechanismassembly(No.MB196)1-133.2.3Removing the CD pickup (See Fig.16) Prior to performing the following procedures, remove the topcover. Also remove the CD changer unit. Also remove the CD changer mechanism.(1) Widen the section f.(2) While keeping the section f wide open, push the section gin the direction of the arrow to remove the shaft, and thenremove the CD pickup.Fig.163.2.4Replacing the loading motor and rotor belt of the CD changer (See Fig .17) Prior to performing the following procedures, remove the topcover. Also open the CD changer tray.(1) Remove the two screws L retaining the CD changer trayloading motor.(2) Remove the two screws M retaining the gear plate and takeit out, after remove the rotor belt from the pulley.Fig.173.2.5Replacing the CD turn table and removing the motor (See Fig.18 ) Prior to performing the following procedures, remove the topcover. Also remove the CD changer unit.(1) Remove the one screws retaining the CD (Turn table).(2) Remove the two screws retaining the stopper brackets onboth sides of the CD changer unit.(3) Remove the stopper brackets from both sides of the CDchanger unit.(4) Pull out the CD tray from the CD changer unit, all the wayand lift the tray to remove.(5) Remove the gear and after push out the tray mo