JVC-MXG850V-cs-sm维修电路原理图.pdf

1-1 MX-G950V/MX-G880V MX-G850V/MX-G750V SERVICE MANUAL COMPACT COMPONENT SYSTEM No.21099 Jul. 2002 COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD. MX-G950V/MX-G880V MX-G850V/MX-G750V Area Suffix UN- Asean US - Singapore UX-Saudi Arabia Safety precautions Preventing static electricity Important for laser products Disassembly method Adjustment method Contents Flow of functional operation until TOC read (CD) Maintenance of laser pickup Replacement of laser pickup Description of major ICs 1-2 1-3 1-4 1-5 1-28 1-33 1-34 1-34 1-3556 COMPACT DIGITAL VIDEO COMPACT DIGITAL AUDIO MX-G950V/MX-G880V MX-G850V/MX-G750V MX-G750V Area Suffix UN- Asean MX-G880V Area Suffix U-Other Areas UN- Asean UX-Saudi Arabia MX-G950V/MX-G850V CA-MXG950VCA-MXG850V CA-MXG880V CA-MXG750V RadioFans.CN 收音机爱 好者资料库 1-2 MX-G950V/MX-G880V MX-G850V/MX-G750V 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 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 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 ! 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 1-3 MX-G950V/MX-G880V MX-G850V/MX-G750V 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 Attention when traverse unit is decomposed 1. Remove the disk stopper and T. bracket on the CD changer mechanism assembly. 2. Disconnect the harness from connector on the CD motor board. 3. CD traverse unit is put up as shown in Fig.1. 4. Solder is put up before the card wire is removed from connector CN601 on the CD servo control board as shown in Fig. 2. (When the wire is removed without putting up solder, the CD pick-up assembly might destroy.) 5. Please remove solder after connecting the card wire with CN601 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 traverse mechanism. Soldering Fig.1 Fig.2 CD changer mechanism assembly CD traverse unit Flexible cable 1-4 MX-G950V/MX-G880V MX-G850V/MX-G750V 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 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. 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 !CAUTION Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check. CLASS 1 LASER PRODUCT 1-5 MX-G950V/MX-G880V MX-G850V/MX-G750V Remove the six screws A on the back of the body. Remove the two screws B 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 method Removing the metal cover (See Fig.1 3) Do not break the front panel tab fitted to the metal cover. CAUTION: Fig.1 (CA-MXG850VU, CA-MXG950VUX) Fig.2 Fig.3 A AA Metal cover Metal cover B Metal cover B Fig.1 (CA-MXG750VUS) A AA Metal cover 1-6 MX-G950V/MX-G880V MX-G850V/MX-G750V Prior to performing the following procedure, remove the metal cover. Disconnect the wire from connector CN705 on the amplifier board. Remove the plastic rivet attaching the main board to the front assembly on the right side of the body. Disconnect the card wire from connector CN661 on the main board. Remove the two screws C on the upper side of the body and the two screws D on the back of the rear panel. Pull both the rear panel and the front panel assembly to the outside, then remove the CD changer mechanism assembly by lifting the rear part of the assembly. 1. 2. 3. 4. 5. Disconnect the card wire from connector CN504 on the inner side of the main board on the right side of the body. Remove the CD mechanism assembly. 6. Removing the CD changer mechanism assembly (See Fig.4, 6) To prevent damage to the CD fitting, be sure to pull both the rear panel and the front panel assembly enough to remove the CD changer mechanism assembly. CAUTION: At this point, one card wire on the underside of the CD mechanism assembly is still connected. REFERENCE: Fig.4 Fig.5 Fig.6 (CA-MXG850VU, CA-MXG950VUX) Front panel assembly CC CD changer mechanism assembly Rear panel Main board CN661 CN504 CD changer mechanism assembly DMain board CN661 Front panel assembly Rear panel CD changer mechanism assemblyFront panel assembly Amplifier board CN705 CN504 Rear panel Plastic rivet Fig.6 (CA-MXG750VUS) CD changer mechanism assembly DMain board CN661 Front panel assembly Rear panel CN504 Plastic rivet 1-7 MX-G950V/MX-G880V MX-G850V/MX-G750V Prior to performing the following procedure, remove the metal cover and CD changer mechanism assembly. Disconnect the card wires from connector CN870, CN871 and CN315 on the main board respectively. Remove the band and disconnect the wire from connector CN703 on the amplifier board. Disconnect the wire from connector CN220 on the transformer board. Remove the two screws F on the bottom of the body. Release the two joints a on the lower right and left sides of the body using a screwdriver, and remove the front panel assembly toward the front. 1. 2. 3. 4. 5. Removing the front panel assembly (See Fig.8 11) Prior to performing the following procedure, remove the metal cover and the CD changer mechanism assembly. Turn over the CD changer mechanism assembly and remove the two screws E attaching the fan. 1. Removing the fan (See Fig.7) Fig.9 Fig.10Fig.11 F (Bottom) Joint a Joint a Front panel assembly Front panel assembly Fig.8 Band Amplifier board CN703 Main board CN870 CN871 CN315 Transformer board CN220 Front panel assembly Fig.7 Fan E E CD changer mechanism assembly 1-8 MX-G950V/MX-G880V MX-G850V/MX-G750V Prior to performing the following procedure, remove the metal cover. Disconnect the card wire from connector CN1 on the tuner board on the right side of the body. Remove the plastic rivet fixing the tuner board. Remove the two screws G on the back of the body. 1. 2. 3. Removing the tuner board (See Fig.12) Prior to performing the following procedure, remove the metal cover and the CD changer mechanism assembly. Remove the screw H attaching the rear cover on the back of the body. Push each tab of the four joints b in the direction of the arrow and release. Remove the sixteen screws G attaching the rear panel. Disengage the joints c on each lower side of the rear panel using a screwdriver and remove the rear panel backward. 1. 2. 3. 4. Removing the rear cover / rear panel (See Fig.13 16) Fig.12 Fig.13 (CA-MXG850VU, CA-MXG950VUX) Fig.14 (CA-MXG850VU, CA-MXG950VUX) CN1 Plastic rivet Tuner board Rear panel Rear panel H G Joint b Joint b Rear cover Rear panel G G GG G G Fig.13 (CA-MXG750VUS) Rear panel H G Joint b Joint b Rear cover Fig.14 (CA-MXG750VUS) Rear panel G G GG G Fig.15 Joint c Rear panel 1-9 MX-G950V/MX-G880V MX-G850V/MX-G750V Prior to performing the following procedure, remove the metal cover, the CD changer mechanism assembly, the rear panel and the tuner board. Disconnect the card wires from connector CN870, CN871 and CN315 on the main board. Disconnect the wires from connector CN704 and CN706 on the amplifier board. Remove the screw I attaching the main board on the right side of the body. Disconnect the wire from connector CN710 on the speaker board. Disconnect connector CN211 and CN212 on the main board from the regulator board. 1. 2. 3. 4. 5. Removing the main board (See Fig.17 19) Fig.17 Fig.19 Fig.18 (CA-MXG850VU, CA-MXG950VUX) Front panel assembly Amplifier board CN704 CN706 Main board CN870 CN871 CN315 Main board Front panel assembly I CN211 CN212 Regulator board Main board Speaker board CN710 Amplifier board CN704, CN706 Fig.16 (CA-MXG850VU, CA-MXG