JVC-MXG50-cs-sm 维修电路原理图.pdf

SERVICE MANUALCOMPACT COMPONENT SYSTEMNo.20978Jul. 2001COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD.MX-G50 MX-G50Area SuffixUSUWUYSingaporeBrazil,Mexico,PeruArgentinaContentsSafety PrecautionsImportant for laser productsPreventing static electricityDisassembly method Wiring connectionAdjustment methodFlow of functional operation until TOC readMaintenance of laser pickupReplacement of laser pickupTrouble shootingDescription of major ICs1-21-31-41-51-201-211-251-261-261-271-3043DISC SKIPVOLUMEVOLUME+RMSMXG50U REMOTE CONTROLSTANDBY/ON12345678910+10SLEEPSUBWOOFERLEVELSOUNDMODEFM MODETAPE A/BFADE MUTINGFM/AMAUX/CD TAPE zzzzzECHOCANCEL/DEMOPRESETCOMPU PLAY CONTROLPLAY & EXCHANGESTANDBY/ONSTANDBYDISC CHANGESOUNDMODESUBWOOFERLEVELCD-R/RW PLAYBACKCOMPACTDIGITAL AUDIOCOMPACT COMPONENT SYSTEMMX-G50CLOCK/TIMERDISPLAYPHONESREPEATPROGRAMREC START/STOPCDREC STARTDUBBINGTAPE ATUNINGSETTAPE BRANDOMEJECTPLAYFULL - LOGIC CONTROLAEJECTREC/PLAYCD SYNCHRO RECORDINGBSP-MXG50SP-MXG50CA-MXG50(No MIC jack and MIC LEVEL volume for UY ver.)RadioFans.CN 收音机爱 好者资料库MX-G501-21. 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 each exposed 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.). 1. 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!Burrs 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.In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the mark nearby are critical for safety. When replacing them, be sure to use the parts of the same type and rating as specified by the manufacturer. (Except the J and C version)RadioFans.CN 收音机爱 好者资料库MX-G501-3Important 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. Reproduction and position of labelsWARNING LABEL!CAUTIONPlease use enough caution not to see the beam directly or touch it in case of an adjustment or operationcheck.CLASS 1LASER PRODUCTMX-G501-4Preventing 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 strapAttention when CD mechanism assembly is decomposed1. Remove the CD changer unit. 2. Remove the CD changer mechanism. 3. Solder is put up before the card wire is removed from the pickup unit connector on the CD mechanism assembly. (When the card wire is removed without putting up solder, the CD pick-up assembly might destroy.) 4. Please remove solder after connecting the card wire with the pickup unit connector when you install picking up in the substrate.*Please refer to Disassembly method in the text for pick-up and how to detach the CD mechanism assembly. SolderingFig.1Fig.2Card wireCard wirePickup unitconnectorPickup unitconnectorCD changer unitCD changer mechanismMX-G501-5Remove the three screws A attaching the metal cover on the back of the body. Remove the six screws B attaching the metal cover on both sides of the body.Remove the metal cover from the body by lifting the rear part of the cover.1.2.3.Disassembly methodRemoving the metal cover (See Fig.1 to 3)Do not break the front panel tab fitted to the metal cover.ATTENTION: Fig.1Fig.2Fig.3Metal coverAAAMetal coverBMetal coverBBBMX-G501-6Prior to performing the following procedure, remove the metal cover.Press the POWER button. Press the OPEN/CLOSE button to eject the CD tray. After drawing the lower part of the tray fitting toward the front, remove the five claws a. Then, while moving the tray fitting upward, remove it. Press the OPEN/CLOSE button to insert the tray.1.2.3.Removing the CD Tray fitting (1)(See Fig. 4 to 6) Turn the black loading pulley gear marked b from the back of the CD changer unit as shown in Fig.7 and draw the CD tray toward the front. After drawing the lower part of the tray fitting toward the front, remove the five claws a. Then, while moving the tray fitting upward, remove it. Push and insert the CD tray manually. 1.2.3.Removing the CD Tray fitting (2) (See Fig. 5 to 7)- How to eject the CD tray without turning on power -Fig.4Fig.5Fig.6Fig.7POWER buttonOPEN/CLOSE buttonCD trayJoint Claw aCD tray fitting(See Fig. 24)CD trayThis slot of the board. b(Loading pulley gear)MX-G501-7Prior to performing the following procedure, remove the metal cover.Disconnect the card wire which is attached with adhesive to the left side of the CD changer unit.Disconnect the card wire from connector CW105 of the CD servo board on the back of the CD changer unit.Disconnect the harness from connector RCW6 & OCW on the inner side of the main board in the body.Remove the two screws C attaching the CD changer unit on the back of the body. Remove the two screws D attaching the CD changer unit on the both side of the body.Draw the CD changer unit upward from behind while pulling the rear panel outward. 1.2.3.4.5.6.Removing the CD changer unit (See Fig.8 to 10)Fig.8Fig.9Fig.10 aFig.10 bCW105CD servo boardCD changer unitMain boardRCW6OCWRear panelCDDRear panelRear panelFront panel assemblyAdhesive card wire strapCD changer unitCD changer unitMX-G501-8Prior to performing the following procedure, remove the metal cover and the CD changer unit.Disconnect the card wire from connector FCW3 and the harness from connector JCW1, JCW2 and HCW3 on the inner side of the main board in the body.Remove the two screws E attaching the front panel assembly on both sides of the body.Remove the screw F attaching the earth terminal extending from the cassette mechanism assembly. Remove the screw G attaching the front panel assembly and main board.Remove the screw H attaching the front panel assembly on the bottom of the body.Release the two joints c on both sides and two joints d on the bottom of the body using a screwdriver. 1.2.3.4.5.6.Removing the front panel assembly (See Fig.11 to 13)Fig.11Fig.12Fig.13Main boardFCW3JCW2JCW1HCW3ACW1ACW2Front panel assemblyJoint cearth wireEFFront panel assemblyGEMain boardHJoint dJoint dJoint cBottom sideMX-G501-9Prior to performing the following procedure, remove the metal cover and the CD changer unit.Remove the four screws I attaching the heat sink cover on the back of the body. Remove the heat sink cover.Remove the four screws J attaching the heat sink & amp. board to the rear panel on the back of the body. Remove the two screws K attaching the speaker terminal to the rear panel on the back of the body. Disconnect the card wire from connector ACW1 and the harness from connector ACW2 on the amp. board. (See Fig.11) After moving the heat sink upward, remove the claws. Then pull out the heat sink & AMP board inward.1.2.3.4.5.Removing the heat sink & amp. board (See Fig.14 and 15)Prior to performing the following procedure, remove the metal cover and CD changer unit.Disconnect the card wire from connector CON01 on the tuner board.Remove the two screws L attaching the tuner board. 1.2.Removing the tuner board(See Fig.15 and 16)Prior to performing the following procedure, remove the metal cover, CD changer unit, heat sink & amp. board and tuner board.Remove the five screws M attaching the rear panel.Remove the screw M attaching the voltage selector. (Only US/ UW)1.2.Removing the rear cover (See Fig.17) Fig.14Fig.15Fig.16Fig.17Rear panelHeat sink coverHeat sink Speaker terminal Tuner terminal KLIIMain boardTuner boardCON01JJMMMMX-G501-10Prior to performing the following procedure, remove the metal cover, CD changer unit and heat sink & amp. board.Remove the four screws P attaching the power ICs to the heat sink.Unsolder the power ICs solder point.1.2.Removing the power ICs (See Fig.19 and 20)Prior to performing the following procedure, remove the metal cover, CD changer unit, heat sink & amp. board tuner board and rear cover.Disconnect the card wire from connector FCW3 and the harness from connector JCW1, JCW2 and HCW3 on the main board. Disconnect the harness from connector PCW1 on the power transformer board.Remove the screw G attaching the main board holder. (See Fig.12)Remove the two screws N attaching the heat sink and bottom chassis. 1.2.3.4.Removing the main board (See Fig. 18)Prior to performing the following procedure, remove the metal cover, heat sink & amp. board, tuner board and rear cover.Disconnect the power cord from connector RCW2 of the power transformer board.Disconnect the harness from connector PCW1 of the power transformer board.Remove the four screws R attaching the power transformer and the screw S attaching the earth terminal.1.2.3.Removing the power transformer (See Fig .21)Fig.21Fig.20Fig.19Fig.18Transfo