JVC-MXKB2-cs-sm 维修电路原理图.pdf

SERVICE MANUALCOPYRIGHT 2004 Victor Company of Japan, LimitedNo.MB2842004/8COMPACT COMPONENT SYSTEMMB28420048MX-KB2,MX-KB1TABLE OF CONTENTS1PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32SPECIFIC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-63DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-74ADJUSTMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-275TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31Area suffixUW - Brazil,Mexico,PeruRadioFans.CN 收音机爱 好者资料库1-2 (No.MB284)SPECIFICATIONDesign and specifications are subject to change without notice.AmplifierOutput Power30 W per channel, min. RMS, driven into 6 at 1kHz, with no more than 10% total harmonic distortion (IEC 268-3)Input Sensitivity/Impedance (1 kHz) AUX IN:500 mV/51 kSpeaker terminals6 - 16 Phones32 - 1 kCassette Deck Section Frequency Response20 mW/ch output into 32 Type I (NORMAL)63 Hz - 12 500 HzWow And Flutter0.15 % (WRMS)CD PlayerCD Capacity3 CDsDynamic Range85 dBSignal-To-Noise Ratio85 dBWow And FlutterUnmeasurableTunerFM Tuner87.5 MHz - 108.0 MHzAM Tuner530 kHz - 1710 kHz (at AM10 kHz channel space)531 kHz - 1710 kHz (at AM9 kHz channel space)UnitDimensions276 mm 315 mm 456 mm (W/H/D)MassApprox. 8 kgSpeaker Specifications SP-MXKB2/SP-MXKB1 (each unit)Type2-way bass-reflex typeSpeaker UnitWoofer : 13 cm cone 1Tweeter : 5cm cone 1Power Handling Capacity30 WImpedance6 Frequency Range65 Hz - 20,000 HzSound pressure level86 dB/WmDimensions208 mm 323 mm 264 mm (W/H/D)Power SpecificationsPower RequirementsAC 110/127/220/230-240V , adjustable with voltage selector, 50/60 HzPower Consumption83 W (power on mode) 13 W (in Standby mode)RadioFans.CN 收音机爱 好者资料库(No.MB284)1-3SECTION 1PRECAUTION1.1Safety Precautions(1) This design of this product contains special hardware andmany circuits and components specially for safety purpos-es. For continued protection, no changes should be madeto the original design unless authorized in writing by themanufacturer. Replacement parts must be identical tothose used in the original circuits. Services should be per-formed by qualified personnel only.(2) Alterations of the design or circuitry of the product shouldnot be made. Any design alterations of the product shouldnot be made. Any design alterations or additions will voidthe manufacturers warranty and will further relieve themanufacture of responsibility for personal injury or propertydamage resulting therefrom.(3) Many electrical and mechanical parts in the products havespecial safety-related characteristics. These characteris-tics are often not evident from visual inspection nor can theprotection afforded by them necessarily be obtained by us-ing replacement components rated for higher voltage, watt-age, etc. Replacement parts which have these specialsafety characteristics are identified in the Parts List of Ser-vice Manual. Electrical components having such featuresare identified by shading on the schematics and by ( ) onthe Parts List in the Service Manual. The use of a substitutereplacement which does not have the same safety charac-teristics as the recommended replacement parts shown inthe Parts List of Service Manual may create shock, fire, orother hazards.(4) The leads in the products are routed and dressed with ties,clamps, tubings, barriers and the like to be separated fromlive parts, high temperature parts, moving parts and/orsharp edges for the prevention of electric shock and firehazard. When service is required, the original lead routingand dress should be observed, and it should be confirmedthat they have been returned to normal, after reassem-bling.(5) Leakage shock hazard testingAfter reassembling the product, always perform an isola-tion check on the exposed metal parts of the product (an-tenna terminals, knobs, metal cabinet, screw heads,headphone jack, control shafts, etc.) to be sure the productis safe to operate without danger of electrical shock.Do notuse a line isolation transformer during this check. Plug the AC line cord directly into the AC outlet. Using aLeakage Current Tester, measure the leakage currentfrom each exposed metal parts of the cabinet, particular-ly any exposed metal part having a return path to thechassis, to a known good earth ground. Any leakage cur-rent must not exceed 0.5mA AC (r.m.s.). Alternate check methodPlug the AC line cord directly into the AC outlet. Use anAC voltmeter having, 1,000 per volt or more sensitivityin the following manner. Connect a 1,500 10W resistorparalleled by a 0.15F AC-type capacitor between an ex-posed metal part and a known good earth ground.Measure the AC voltage across the resistor with the ACvoltmeter. Move the resistor connection to each exposed metalpart, particularly any exposed metal part having a returnpath to the chassis, and measure the AC voltage acrossthe resistor. Now, reverse the plug in the AC outlet andrepeat each measurement. Voltage measured any mustnot exceed 0.75 V AC (r.m.s.). This corresponds to 0.5mA AC (r.m.s.). 1.2Warning(1) This equipment has been designed and manufactured tomeet international safety standards.(2) It is the legal responsibility of the repairer to ensure thatthese safety standards are maintained.(3) Repairs must be made in accordance with the relevantsafety standards.(4) It is essential that safety critical components are replacedby approved parts.(5) If mains voltage selector is provided, check setting for localvoltage.1.3CautionBurrs formed during molding may be left over on some partsof the chassis. Therefore, pay attention to such burrs in the case of pre-forming repair of this system.1.4Critical parts for safetyIn regard with component parts appearing on the silk-screenprinted side (parts side) of the PWB diagrams, the parts that areprinted over with black such as the resistor ( ), diode ( )and ICP ( ) or identified by the mark nearby are criticalfor safety. When replacing them, be sure to use the parts of thesame type and rating as specified by the manufacturer. (This regulation dose not Except the J and C version)Good earth groundPlace this probe on each exposedmetal part.AC VOLTMETER(Having 1000 ohms/volts,or more sensitivity)1500 10W0.15 F AC TYPE1-4 (No.MB284)1.5Preventing static electricityElectrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric, etc. is discharged, can destroy the laserdiode in the traverse unit (optical pickup). Take care to prevent this when performing repairs.1.5.1 Grounding to prevent damage by static electricityStatic electricity in the work area can destroy the optical pickup (laser diode) in devices such as laser products. Be careful to use proper grounding in the area where repairs are being performed. (1) Ground the workbenchGround the workbench by laying conductive material (such as a conductive sheet) or an iron plate over it before placing thetraverse unit (optical pickup) on it.(2) Ground yourselfUse an anti-static wrist strap to release any static electricity built up in your body. (3) Handling the optical pickup In order to maintain quality during transport and before installation, both sides of the laser diode on the replacement opticalpickup are shorted. After replacement, return the shorted parts to their original condition. (Refer to the text.) Do not use a tester to check the condition of the laser diode in the optical pickup. The testers internal power source can easilydestroy the laser diode. 1.6Handling 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 thereplacement procedure in the text. Remove the anti-static pin when replacing the traverse unit. Be careful not to take too long atime when attaching it to the connector. (3) Handle the flexible cable carefully as it may break when subjected to strong force. (4) I t is not possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it.1.7Attention when traverse unit is decomposed*Please refer to Disassembly method in the text for the pickup unit. Apply solder to the short land sections before the flexible wire is disconnected from the connecto on the servo board. (If the flexiblewire is disconnected without applying solder, the pickup may be destroyed by static electricity.) In the assembly, be sure to remove solder from the short land sections after connecting the flexible wire.1MConductive material(conductive sheet) or iron palate(caption)Anti-static wrist strapCD pickup boardShort-circuit pointCard wire(No.MB284)1-51.8Important 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 CD,MD and DVD 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 here in may result in hazardous radiation exposure.REPRODUCTION AND POSITION OF LABELSCAUTION : Visible and Invisible laser radiation when open and interlock failed or defeated.AVOID DIRECT EXPOSURE TO BEAM. (e)VARNING : Synlig ochosynling laserstrlning nr den ppnas och sprren rurkopplad. Betrakta ejstrlen. (s)VARO : Avattaessa ja suojalukitusohitettuna tai viallisena olet alttiina nkyvlle ja nkymttmllelasersteilylle. Vlt steenkohdistumista suoraan itseesi. (f)ADVARSEL : Synlig og usynliglaserstrling nr maskinen erben eller interlocken fejeler.Undg direkte eksponering til strling. (d)!Please use enough caution not to see the beam directly or touch it in case of an adjustment or operationcheck.CLASS 1LASER PRODUCTCAUTION : Visible and Invisible laser radiation when open and interlock failed or defeated.AVOID DIRECT EXPOSURE TO BEAM. (e)VARNING : Synlig ochosynling laserstrlning nr den ppnas och sprren rurkopplad. Betrakta ejstrlen. (s)VARO : Avattaessa ja suojalukitusohitettuna tai viallisena olet alttiina nkyvlle ja nkymttmllelasersteilylle. Vlt steenkohdistumista suoraan itseesi. (f)ADVARSEL : Synlig og usynliglaserstrling nr maskinen erben eller interlocken fejeler.Undg direkte eksponering til strling. (d)WARNING LABEL1-6 (No.MB284)SECTION 2SPECIFIC SERVICE INSTRUCTIONSThis service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.(No.MB284)1-7SECTION 3DISASSEMBLY3.1Main body3.1.1Removing the top cover / side cover (R) and (L) (See Fig.1 to 6)(1) From the back of the body, remove the two screws A at-taching the top cover.(2) From both sides of the body, remove the four screws B at-taching the top cover and the side cover (R) and (L). Movethe top cover in the direction of the arrow to release fromthe front panel at the two joints a.(3) Remove the six screws D on the back of the body and thetwo screws E on the side of the body. Move the side cover(R) and (L) backward to release the four joints b on the bot-tom of the side covers.Fig.1Fig.2AATop coverTop coverFront panel assemblySide cover (R)BaB1-8 (No.MB284)Fig.3Fig.4Fig.5Fig.6DDSide cover (R)Side cover (L)Side cover (R)Front panel assemblyE bE bSide cover (L)Front panel assemblyJoint b(No.MB284)1-93.1.2Removing the CD fitting (See Fig.7 to 9) Prior to performing the following procedure, remove the topcover / side cover (R) and (L).Caution:For preventing from damage, make sure to remove the CD fit-ting before detaching the CD changer mechanism unit.(1) Push STANDBY / ON key to turn power on.(2) Push CD TRAY EJECT key.(3) Move the CD fitting in the direction of the arrow to releasefrom the CD tray at two joints d.(4) Push STANDBY / ON key to close the tray.3.1.3Removing the CD fitting (See Fig.8 to 10) Prior to performing the following procedure, remove the topcover / side cover(R) and (L).(1) Turn over the CD changer mechanism unit and turn theloading pulley gear at e in the inner part of the notch of themain board to move the CD tray forward.(2) Move the CD fitting in the direction of the arrow to releasefrom the CD tray at two joint d.(3) Manually push and close the CD tray.Fig.7Fig.8Fig.9Fig.10CD TRAY EJECTSTANDBY / ONCD fittingCD changer mechanism unitFront panel assemblydCD fittingCD trayCD trayeMain boardCD changer mechanism Loading pullygear1-10 (No.MB284)3.1.4Removing the CD changer mechanism unit (See Fig.11 to 16) Prior to performing the following procedure, remove the topcover / side cover (R) and (L), and the CD fitting.(1) Disconnect the wire from connector CN601 on the turnerboard on the right side of the body.(2) Disconnect the wire from connector CN504 on the AUXboard on the inner side of the front panel.(3) Disconnect the wire from connector CN801, CN802 andCN803 on the power board.(4) Disconnect the wire from connector CN100, CN101 andCN207 on the main board at the bottom of the CD changermechanism unit, and disconnect the card wire from con-nector CN103. If necessary, release the band attaching thewires.(5) From the side of the body, remove the two screws F attach-ing the CD changer mechanism unit.(6) From the back of the body, remove the two screws G at-taching the CD changer mechanism unit.(7) Move the CD changer mechanism unit in the direction ofthe arrow while pulling the rear panel backward, and re-move the CD changer mechanism unit.Fig.11Fig.12Turner board CN601AUX board CN504Front panel assemblyFCD changer mechanism unitRear panelFront panel assemblyFCD changer mechanism unitRear panel(No.MB284)1-11Fig.13Fig.14Fig.15Fig.16AUX board CN504Front panel assemblyCN802Power boardCN803CN801CD changer mechanism unitCN207CN101CN100CN103Main boardCD changer mechanism unitGGRear panel1-12 (No.MB284)3.1.5Removing the tuner board (See Fig.17, 18) Prior to performing the following procedure, remove the topcover / side cover (R) and (L).(1) Disconnect the wire from connector CN601 on the tunerboard.(2) From the back of the body, remove the two screws H, thetwo screws J and the two screws K attaching the tunerboard respectively.(3) Remove the two screws L attaching the tuner board holder.Caution:You can remove the tuner board without removing the CDchanger m