JVC-MXJ270V-cs-sm 维修电路原理图.pdf

SERVICE MANUALCOMPACT COMPONENT SYSTEMNo.20880Nov. 2000COPYRIGHT 2000 VICTOR COMPANY OF JAPAN, LTD.MX-J270VContentsSafety PrecautionsImportant for laser productsPreventing static electricityDisassembly methodAdjustment methodFlow of functional operation until TOC readMaintenance of laser pickupReplacement of laser pickupDescription of major ICs1-21-31-41-51-221-261-271-271-28Area SuffixUSUXSingaporeSaudi ArabiaPlayBackControlVIDEO CDCDCDCDSTANDBYVOLUMECDCDCDFM /AM CDPLAYREC/PLAYAUTO REVERSETAPEMIC LEVEL1 BITDUAL D/A CONVERTERAUXPHONESMX-J270V+MICMINMAXAUTO REVERSEPLAY & EXCHANGERVIDEO CDNTSC/PAL COMPATIBILITYRECSTART/STOPKEY CONTROLDUBBINGCD REC STARTNTSC/PAL PAL AUTORANDOMREPEAT PRESET +TUNING / VCD NUMBERREVERSE MODETAPE A/BSOUND MODEACTIVE BASS EX.PREVNEXTECHO+SELECTMPX/V.REPLACE/V.MASKINGEJECTEJECT1C DTAPECLOCKECHOSETTIMERSLEEPSELECT +RM-SMXJ111V REMOTE CONTROL23456PLAY MODESTILLCD3CD2CD1A TAPE - BREC PAUSESOUNDMODEVOLUMEKEY CONTROLSHIFTFM MODE78910+10 HIGHLIGHTON SCREENV.INTRO PREVNEXTRETURNSELECTFM/AMAUXi iI IMX-J270VSP-MXJ270VCA-MXJ270VSP-MXJ270VRadioFans.CN 收音机爱 好者资料库MX-J270V1-2Safety Precautions1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should be made to the original design unless authorized in writing by the manufacturer. Replacement parts must be identical to those used in the original circuits. Services should be performed by qualified personnel only.2. Alterations of the design or circuitry of the product should not be made. Any design alterations of the product should not be made. Any design alterations or additions will void the manufacturers warranty and will further relieve the manufacture of responsibility for personal injury or property damage resulting therefrom.3. Many electrical and mechanical parts in the products have special safety-related characteristics. These characteristics are often not evident from visual inspection nor can the protection afforded by them necessarily be obtained by using replacement components rated for higher voltage, wattage, etc. Replacement parts which have these special safety characteristics are identified in the Parts List of Service Manual. Electrical components having such features are identified by shading on the schematics and by ( ) on the Parts List in the Service Manual. The use of a substitute replacement which does not have the same safety characteristics as the recommended replacement parts shown in the Parts List of Service Manual may create shock, fire, or other hazards.4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the like to be separated from live parts, high temperature parts, moving parts and/or sharp edges for the prevention of electric shock and fire hazard. When service is required, the original lead routing and dress should be observed, and it should be confirmed that they have been returned to normal, after re-assembling.5. Leakage currnet check (Electrical shock hazard testing)After re-assembling the product, always perform an isolation check on the exposed metal parts of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control shafts, etc.) to be sure the product is safe to operate without danger of electrical shock.Do not use a line isolation transformer during this check.Plug the AC line cord directly into the AC outlet. Using a Leakage Current Tester, measure the leakage current from each exposed metal parts of the cabinet , particularly any exposed metal part having a return path to the chassis, to a known good earth ground. Any leakage current must not exceed 0.5mA AC (r.m.s.)Alternate check methodPlug the AC line cord directly into the AC outlet. Use an AC voltmeter having, 1,000 ohms per volt or more sensitivity in the following manner. Connect a 1,500 10W resistor paralleled by a 0.15 F AC-type capacitor between an exposed metal part and a known good earth ground.Measure the AC voltage across the resistor with the AC voltmeter. Move the resistor connection to eachexposed metal part, particularly any exposed metal part having a return path to the chassis, and meausre the AC voltage across the resistor. Now, reverse the plug in the AC outlet and repeat each measurement. voltage measured Any must not exceed 0.75 V AC (r.m.s.). This corresponds to 0.5 mA AC (r.m.s.). Warning1. This equipment has been designed and manufactured to meet international safety standards.2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.3. Repairs must be made in accordance with the relevant safety standards.4. It is essential that safety critical components are replaced by approved parts.5. If mains voltage selector is provided, check setting for local voltage.Good earth groundPlace this probe on each exposedmetal part.AC VOLTMETER(Having 1000 ohms/volts,or more sensitivity)1500 10W0.15 F AC TYPE!CAUTIONBurrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system.RadioFans.CN 收音机爱 好者资料库MX-J270V1-3Important for laser products1.CLASS 1 LASER PRODUCT2.DANGER : Invisible laser radiation when open and inter lock failed or defeated. Avoid direct exposure to beam.3.CAUTION : There are no serviceable parts inside theLaser Unit. Do not disassemble the Laser Unit. Replace the complete Laser Unit if it malfunctions.4.CAUTION : The compact disc player uses invisible laserradiation and is equipped with safety switches whichprevent emission of radiation when the drawer is open and the safety interlocks have failed or are de feated. It is dangerous to defeat the safety switches.5.CAUTION : If safety switches malfunction, the laser is able to function.6.CAUTION : Use of controls, adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.VARNING : Osynlig laserstrlning r denna del r ppnad och sprren r urkopplad. Betrakta ej strlen.VARO : Avattaessa ja suojalukitus ohitettaessa olet alttiina nkymttmlle lasersteilylle.l katso steeseen.ADVARSEL : Usynlig laserstrling ved bning , nr sikkerhedsafbrydere er ude af funktion. Undg udsttelse for strling.ADVARSEL : Usynlig laserstrling ved pning,nr sikkerhetsbryteren er avslott. unng utsettelse for strling.REPRODUCTION AND POSITION OF LABELSWARNING LABELDANGER : Invisibie laser radiation when open and interlock or defeated.AVOID DIRECT EXPOSURE TO BEAM (e)VARNING : Osynlig laserstrlning r denna del r ppnad och sprren r urkopplad. Betrakta ej strlen. (s)VARO : Avattaessa ja suojalukitus ohitettaessa olet alttiina nkymttmlle lasersteilylle.l katso steeseen. (d)ADVARSEL :Usynlig laserstrling ved bning , nr sikkerhedsafbrydere er ude af funktion. Undg udsttelse for strling. (f)CLASS 1LASER PRODUCT!CAUTIONPlease use enough caution not to see the beam directly or touch it in case of an adjustment or operationcheck.MX-J270V1-4Preventing static electricity1. Grounding to prevent damage by static electricity Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.2. About the earth processing for the destruction prevention by static electricity In the equipment which uses optical pick-up (laser diode), optical pick-up is destroyed by the static electricity of the work environment.Be careful to use proper grounding in the area where repairs are being performed. 2-1 Ground the workbench Ground the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing the traverse unit (optical pickup) on it.2-2 Ground yourself Use an anti-static wrist strap to release any static electricity built up in your body. 3. Handling the optical pickup1. In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement optical pickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.)2. Do not use a tester to check the condition of the laser diode in the optical pickup. The testers internal power source can easily destroy the laser diode. 4. Handling 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 the replacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long a time when attaching it to the connector. 3. Handle the flexible cable carefully as it may break when subjected to strong force. 4. It is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn itConductive material (conductive sheet) or iron plate(caption)Anti-static wrist strapMX-J270V1-5Remove the six screws A attaching the metal cover on the back of the body.Remove the two screws B on both sides of the body.Remove the metal cover from the body while lifting up the rear part of the metal cover.1.2.3.Removing the metal cover (See Fig.1 to 3)Disassembly methodFig.3Fig.2Fig.1Metal coverAAAMetal coverBMetal coverBMX-J270V1-6Prior to performing the following procedures, remove the metal cover.Disconnect the card wire from connector CN308 and CN309 connecting the CD servo board and the main board.Disconnect the harness from CN310 on the main board.Remove the two screws C attaching the CD changer mechanism assembly on the top of the body.Remove the plastic rivet a fixing the main board to the front panel assembly on the left side of the body.Remove the two screws D from the rear panel.Cut off the band b and band c which bundle two harnesses coming from the MIC/headphone board and one harness coming from the video board, respectively.Detach upward the rear part of the CD changer mechanism assembly while pulling the front panel assembly and the rear panel outward, then pull out the front part backward and upward.1.2.3.4.5.6.7.Removing the CD changer mechanism assembly (See Fig.4 to 7)Fig.6Fig.5Fig.4Fig.7Pull outwardCMain boardCN303Plastic rivet a CD changer mechanism assemblyRear panelFront panelassemblyDRear panelCD changer mechanism assemblyCD changer mechanismassemblyRear panelFront panel assemblyPull outwardMain boardMain boardBand bBand cCN308CN309CN310MX-J270V1-7Prior to performing the following procedures, remove the metal cover and the CD changer mechanism assembly.Disconnect the card wires from connector CN302, CN306, CN307 and the harness from CN301, CN305 on the inside of the main board.Turn over the body and remove the four screws E.Release the joint d and e on both sides of the body using a screwdriver, and detach the front panel assembly toward the front.1.2.3.Removing the front panel assembly (See Fig.8 to 11)Fig.9Fig.8Fig.10Fig.11Main boardCN301CN302CN306CN307CN312CN305EFront panel assemblyFront panel assemblyJoint dFront panel assemblyJoint e(Bottom)MX-J270V1-8Prior to performing the following procedures, remove the metal cover and the CD changer mechanism assembly.It is not necessary to remove the front panel assembly.Remove the two screws F and the rear cover on the back of the body.Remove the four screws G and the seven screws H attaching the main board and the heat sink to the rear panel.Remove the screw I attaching the rear panel to the chassis base.Remove the two screws J attaching the rear panel to the voltage selector.Remove the two screws K attaching the rear panel to the video board.Release the lower two joints f and g on both sides of the rear panel using a screwdriver and detach the rear panel backwards.1.2.3.4.5.6.Removing the rear cover, the rear panel, the voltage selector and the video board (See Fig.12 to 15)Fig.12Fig.13Fig.14Fig.15IRear panelGRear panelFFRear coverHGHRear panelJoint fRear panelJoint g(To Earth bracket)JKMX-J270V1-9Prior to performing the following procedures, remove the metal cover, the CD changer mechanism assembly, the rear cover, the rear panel, the voltage selector and the video board.It is not necessary to remove the front panel assembly.Disconnect the card wires from connector CN302, CN306, CN307 and the harnesses from CN301, CN305, CN901A and CN901B on the inside of the main board.Disconnect the harness from CN312 on the video board.From the right side of the body, remove the screw M attaching the main board to the chassis base.1.2.3.Removing the main board (See Fig.16 to 19)Prior to performing the following procedure, remove the rear cover, rear panel, voltage selector and the video board.Remove the two screws N attaching the heat sink to the main board. Remove the IC bracket 1 and 2 on the back of the heat sink.Pull out the heat sink toward you.1.2.To remove the heat sink from the main boardPrior to performing the following procedures, remove the main board.Release the two joints h and i using a screwdriver and detach the DSP board toward you.1.Removing the DSP board (See Fig.19)Fig.16Fig.17MMain boardMain boardCN306CN307CN302CN305CN301CN901A,CN901BFig.18Heat sinkNMain boardFig.19Heat sinkIC bracket 2IC bracket 1CN312DSP boardDSP boardJoint iJoint hDSP boardVideo boardMX-J270V1-10Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly and the voltage selector.Disconnect the harness from connector CN901A and CN901B on the inside of the main board.Cut off the tie band j of the power transformer assembly and unsolder the power cord.(Make sure to bundle the wires after repair.)Remove the four screws O attaching the power transformer assembly.When removing the power transformer assembly with the power cord, remove the rear panel and pull out the power cord stopper from the bottom chassis upward.1.2.3.Removing the power transformer assembly (See Fig.20 to 22)Fig.20Fig.21Fig.22OPower transformer assemblyCN901A,CN901BOPower transformer assemblyTie band jPower transformer assemblyPower cord stopperRear panelVoltage selector boardVoltage selector boardVoltage selector boardVideo boardVideo boardFront panelassemblyMX-J270V1-11Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly and the front panel assembly.Remove the two screws P attaching the MIC /headphone board.Pull out the MIC LEVEL knob from front side.Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly and the front panel assembly.Disconnect the card wire from connector CN305 on the cassette amplifier board.Remove the eight screws Q attaching the cassette mechanism assembly. Detach the cassette mechanism assembly toward you.1.2.1.2.3.Prior to performing the following procedure, remove the cassette mechan