JVC-MXK50-cs-sm 维修电路原理图.pdf
SERVICE MANUALCOMPACT COMPONENT SYSTEMNo.21121Nov. 2002COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD.MX-K50MX-K50ContentsSafety PrecautionsPreventing static electricityImportant for laser productsDisassembly method Wiring connectionAdjustment methodFlow of functional operation until TOC readMaintenance of laser pickupReplacement of laser pickupTrouble shootingDescription of major ICs1-21-31-41-51-181-191-231-241-241-251-2843Area suffixUW - Brazil,Mexico,PeruU - Other AreasSP-MXK50SP-MXK50CA-MXK50DISC CHANGECOM P U PLAY CONTROLSTANDBY/ONSTANDBYCD-R/RW PLAYBACKTUNINGCLOCK/TIMERDISPLAYPHONESREPEATREC START/STOPCD REC STARTDUBBINGPROGRAMRANDOMTAPE BTAPE ATAPECDFM /AMACTIVE BASSEX. LEVELSOUNDMODEMX-K50CD 2CD 3ACTIVE BASS EXTENSIONCD3FULL - LOGIC CONTROLCD SYNCHRO RECORDINGAUXCD 1DISCSKIPVOLUMEVOLUME+STANDBY/ON12345678910+10SLEEPACTIVE BASSEX. LEVELSOUNDMODEFM MODETAPE A/BKARAOKEECHOFADE MUTINGFM/AMAUXCD TAPE RMSMXK50U REMOTE CONTROLRadioFans.CN 收音机爱 好者资料库MX-K501-21. 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. (This regulation does not correspond to J and C version.)RadioFans.CN 收音机爱 好者资料库1-3MX-K50Preventing 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 wirePicup unitconnectorPicup unitconnectorCD changer unitCD changer mechanismMX-K501-4Important 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 laser radiation and is equipped with safety switches which prevent emission of radiation when the drawer is open and the safety interlocks have failed or are defeated. 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.!Please use enough caution not to see the beam directly or touch it in case of an adjustment or operationcheck.Position of labelsWARNING LABELCLASS 1LASER PRODUCT1-5MX-K50Remove 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) ONE POINT How to eject the CD tray (see fig.2)Although it will end if the OPEN/CLOSE button is pushed when a power supply can be taken, when that is not right, CD tray will be opened manually.Turn the loading pulley gear at the bottom of the CD changer unit as shown in Fig.2 and draw the CD tray toward the front. Removing the CD tray fitting(See Fig. 3)Prior to performing the following procedure, eject the CD tray.After drawing the lower part of the tray fitting toward the front, remove the five claws. Then, while moving the tray fitting upward, remove it.1.Prior to performing the following procedure, remove the metal cover and CD tray fitting.Remove the card wire attached to CD changer unit on the adhesion tape.Disconnect the card wire from the connector CW105 on the CD board.Disconnect the harness from the connector RCW6 on the main board.Remove the two screws C attaching the CD changer unit to the rear panel.Remove the two screws D attaching the CD changer unit to both sides of the front panel assembly.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.4 to 7)Fig.1Fig.2Fig.3Metal coverAB(both sides)Joint ClawCD tray fitting Loading pulley gear(See fig.1)Fig.4CD changer unitCard wireAdhesion tapeMX-K501-6Prior to performing the following procedure, remove the metal cover and CD changer unit.Disconnect the card wire from the connector FCW3 on the main board.Disconnect the harness from the connector ECW1, JCW1, JCW2 and HCW3 on the main board.Remove the screw E attaching the earth terminal extending from the cassette mechanism assembly.Remove the two screws F attaching the front panel assembly to both sides of the body.Remove the screw G attaching the main board to the front panel assembly.Remove the screw H attaching the front panel assembly to bottom of the body.Release the two joints1 and two joints2, and detach the front panel assembly toward the front.1.2.3.4.5.6.7.Removing the front panel assembly (See Fig.8 to 10)Fig.6Fig.7Fig.5RCW6CD boardCD changer unitMain boardCW105Rear panelCD(both sides)Rear panelCD changer unitFront panelassemblyFig.8Fig.9Main boardAmp. boardFCW3JCW2JCW1ECW1HCW3ACW1ACW2Front panelassemblyJoint1(both sides)F(both sides)Joint1(both sides)F(both sides)E(fixing the earth wire)Front panelassemblyGMain board1-7MX-K50Prior to performing the following procedure, remove the metal cover and CD changer unit.Disconnect the card wire from the connector ACW1 and the harness from the connector ACW2 on the amp. board. Remove the four screws I attaching the heat sink cover to the rear panel. Remove the heat sink cover.Remove the four screws J attaching the heat sink and two screws K attaching the speaker terminal to the rear panel. After moving the heat sink upward, remove the claws. Then pull out the heat sink & amp. board inward.1.2.3.4.Removing the heat sink & amp. board (See Fig.8, 11 and 12)Prior to performing the following procedure, remove the metal cover.Disconnect the card wire from the connector CON01 on the tuner board.Remove the two screws L attaching the tuner board to the rear panel. 1.2.Removing the tuner board (See Fig.12 and 13)Prior to performing the following procedure, remove the metal cover, CD changer unit, heat sink & amp. board and tuner board.Remove the screw M, screw N and three screws O attaching the rear panel.1.Removing the rear panel (See Fig.12)Fig.10HJoint2(Bottom side)Fig.11Rear panelHeat sinkcoverIIFig.12Heat sink ClawsSpeakerterminal KMONLRear panelJJFig.13Main boardTuner boardCON01Rear panelMX-K501-8Prior to performing the following procedure, remove the metal cover, CD changer unit and heat sink & amp. board.Unsolder the power IC solder point.Remove the two screws Q attaching the power IC to the heat sink.1.2.Removing the power IC (See Fig.15 and 16)Prior to performing the following procedure, remove the metal cover, CD changer unit and rear panel.Disconnect the card wire from the connector FCW3 and the harness from the connector ECW1, JCW1, JCW2 and HCW3 on the main board. Disconnect the harness from the connector PCW1 on the fuse board.Remove the screw G attaching the main board to the front panel assembly. (See Fig.9)Remove the two screws P attaching the heat sink to the bottom chassis.Pull out the voice board, if needed.1.2.3.4.5.Removing the main board (See Fig. 14)Removing the power cord (See Fig. 14)Prior to performing the following procedure, remove the metal cover, CD changer unit and rear panel.Disconnect the power cord from the connector RCW2 on the trans. board and pull up the power cord stopper upward.1.Prior to performing the following procedure, remove the metal cover, CD changer unit and heat sink & amp. board.Remove the screw N attaching the trans. board to the rear panel (see fig.12).Disconnect the power cord from the connector RCW2 on the trans. board.Disconnect the harness from the connector PCW1 on the fuse board.Remove the four screws R attaching the power transformer on the bottom chassis.1.2.3.4.Removing the power transformer (See Fig .17)Fig.16Fig.17Fig.15Fig.14Fuse boardTrans. boardFuse boardTrans. boardPower cordBottom chassisPower cordstopperPQRHeat sinkHeat sinkAmp. boardFCW3JCW2RCW2JCW1ECW1PCW1Heat sinkPower transformerPower IC solder pointMain boardRCW2PCW1HCW3Amp. board(reverse side)Bottom chassisVoice board1-9MX-K50Disconnect the card wire from the connector UCW3, UCW4, UCW5 and UCW6 on the front board.Remove the six screws B attaching the front board. Disconnect the card wire from the connector UCW2 on the front board.1.2.3.Removing the front board (See Fig.1)Discon
