JVC-MXJ270V-cs-sm 电路图 维修手册.pdf

SERVICE MANUAL COMPACT COMPONENT SYSTEM No.20880 Nov. 2000 COPYRIGHT 2000 VICTOR COMPANY OF JAPAN, LTD. MX-J270V Contents Safety Precautions Important for laser products Preventing static electricity Disassembly method Adjustment method Flow of functional operation until TOC read Maintenance of laser pickup Replacement of laser pickup Description of major ICs 1-2 1-3 1-4 1-5 1-22 1-26 1-27 1-27 1-28 Area Suffix US UX Singapore Saudi Arabia PlayBack Control VIDEO CD CD CD CD STANDBY VOLUME CD CD CD FM /AM CD PLAYREC/PLAY AUTO REVERSE TAPE MIC LEVEL 1 BIT DUAL D/A CONVERTER AUX PHONES MX-J270V + MIC MINMAX AUTO REVERSE PLAY & EXCHANGER VIDEO CDNTSC/PAL COMPATIBILITY REC START/STOP KEY CONTROL DUBBING CD REC STARTNTSC/PAL PAL AUTO RANDOM REPEAT PRESET +TUNING / VCD NUMBER REVERSE MODETAPE A/B SOUND MODEACTIVE BASS EX. PREVNEXT ECHO + SELECT MPX/V.REPLACE/V.MASKING EJECTEJECT 1 C D TAPE CLOCK ECHOSET TIMER SLEEPSELECT + RM-SMXJ111V REMOTE CONTROL 23 456 PLAY MODE STILLCD3CD2CD1 A TAPE - BREC PAUSE SOUND MODE VOLUME KEY CONTROL SHIFTFM MODE 789 10+10 HIGHLIGHT ON SCREEN V.INTRO PREVNEXTRETURNSELECT FM/AMAUX i i I I MX-J270V SP-MXJ270VCA-MXJ270VSP-MXJ270V RadioFans.CN 收音机爱 好者资料库 MX-J270V 1-2 Safety Precautions 1. 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 method Plug 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.). Warning 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 ground Place this probe on each exposed metal part. AC VOLTMETER (Having 1000 ohms/volts, or more sensitivity) 1500 10W 0.15 F AC TYPE !CAUTION 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. RadioFans.CN 收音机爱 好者资料库 MX-J270V 1-3 Important for laser products 1.CLASS 1 LASER PRODUCT 2.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 the Laser 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 LABELS WARNING LABEL DANGER : 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 1 LASER PRODUCT !CAUTION Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check. RadioFans.CN 收音机爱 好者资料库 MX-J270V 1-4 Preventing static electricity 1. 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 pickup 1. 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 it Conductive material (conductive sheet) or iron plate (caption) Anti-static wrist strap MX-J270V 1-5 Remove 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 method Fig.3 Fig.2 Fig.1 Metal cover A A A Metal cover B Metal cover B MX-J270V 1-6 Prior 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.6 Fig.5 Fig.4 Fig.7 Pull outward C Main board CN303 Plastic rivet a CD changer mechanism assembly Rear panel Front panel assembly D Rear panel CD changer mechanism assembly CD changer mechanism assembly Rear panel Front panel assembly Pull outward Main board Main board Band b Band c CN308 CN309 CN310 MX-J270V 1-7 Prior 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.9 Fig.8 Fig.10 Fig.11 Main board CN301 CN302 CN306 CN307 CN312 CN305 E Front panel assembly Front panel assembly Joint d Front panel assembly Joint e (Bottom) MX-J270V 1-8 Prior 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.12 Fig.13 Fig.14 Fig.15 I Rear panel G Rear panel FF Rear cover H G H Rear panel Joint f Rear panel Joint g (To Earth bracket) J K MX-J270V 1-9 Prior 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 board Prior 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.16 Fig.17 M Main board Main boardCN306 CN307 CN302 CN305 CN301 CN901A,CN901B Fig.18 Heat sink N Main board Fig.19 Heat sink IC bracket 2 IC bracket 1 CN312 DSP board DSP board Joint i Joint h DSP board Video board MX-J270V 1-10 Prior 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.20 Fig.21 Fig.22 O Power transformer assembly CN901A,CN901B O Power transformer assembly Tie band j Power transformer assembly Power cord stopper Rear panel Voltage selector board Voltage selector board Voltage selector board Video board Video board Front