JVC-MXGA8-cs-sm 维修电路原理图.pdf

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1、SERVICE MANUALCOPYRIGHT 2003 VICTOR COMPANY OF JAPAN, LIMITEDNo.MB0802004/1COMPACT COMPONENT SYSTEMMB080200312MX-GA8TABLE OF CONTENTS1PRECAUTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-32SPECIF

2、IC SERVICE INSTRUCTIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-53DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-64ADJUSTM

3、ENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-205TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

4、4SP-MXGA8SP-MXGA8CA-MXGA8CD 1DISC CHANGEDISPLAYCD 2CD 3TUNINGSTANDBYRANDOMPROGRAMDUBBINGREC START/ STOPCD RECSTARTSETCLOCK/ TIMERCANCEL/ DEMOSOUNDTURBOTAPE A / BREPEATPHONESTUNINGC O M P A C T C O M P O N E N T S Y S T E M M X - G A 8R O C KP O PCLASSICD A N C EH A L LSTADIUMSOUNDMODEVOLUMEEJECTEJEC

5、TSUBWOOFER LEVELPRESETSTANDBY/ONBEEPArea SuffixJW - Mexico,PanamaRadioFans.CN 收音机爱 好者资料库1-2 (No.MB080)SPECIFICATIONDesign and specifications are subject to change without notice.Amplifier section Output PowerSUBWOOFERS120 W per channel, min. RMS, driven into 6 at 63 Hz with no morethan 10% total har

6、monic distortion.MAIN SPEAKERS 60 W per channel, min. RMS, driven into 4 at 1 kHz with no morethan 10% total harmonic distortion.Audio input sensitivity/Impedance (at 1 kHz, measured at MAIN SPEAKERS)AUX400 mV/50 kSpeakers/ImpedanceSubwoofers6 - 16 Main speakers4 - 8 TunerFM tuning range87.50 MHz -

7、108.00 MHzAM tuning range530 kHz - 1 710 kHzCD playerCD Capacity 3 CDsDynamic range 85 dBSignal-to-noise ratio 85 dBCassette deckFrequency response Normal (type I)50 Hz - 14 000 HzWow and flutter0.15% (WRMS)GeneralPower requirementAC 120 V , 60 HzPower consumption160 W (at operation)18 W (on standby

8、)Dimensions (approx.)270 mm 317 mm 453 mm (W/H/D)Mass (approx.)8.8 kgSpeaker section Type3-way bass-reflex typeSpeaker unitsSubwoofer13.5 cm cone 1Main Woofer16 cm cone 1Tweeter5 cm cone 1Power handling capacity Subwoofer120 WMain speaker60 WImpedanceSubwoofer6 Main speaker4 Frequency rangeSubwoofer

9、30 Hz - 70 HzMain speaker70 Hz - 20 000 HzSound pressure levelSubwoofer73 dB/WmMain speaker86 dB/WmDimensions (approx.)290 mm 317 mm 336 mm (W/H/D)Mass (approx.)5.5 kg eachRadioFans.CN 收音机爱 好者资料库(No.MB080)1-3SECTION 1PRECAUTION1.1Safety Precautions(1) This design of this product contains special har

10、dware 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

11、 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 person

12、al 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 replacemen

13、t 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

14、 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, barri

15、ers 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 norm

16、al, 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 w

17、ithout 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

18、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 resistorparalle

19、led 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 t

20、he 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

21、) 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, c

22、heck 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 sid

23、e (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 regul

24、ation 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.MB080)1.5Preventing static electricityElectrostatic discharge (ESD), which occurs when static electricity stored

25、 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 dev

26、ices such as CD players. 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) Groun

27、d 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, retu

28、rn 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 traver

29、se 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

30、 traverse unit. Be careful not to take too longa time 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 t

31、raverse unit is decomposed*Please refer to Disassembly method in the text for the CD pickup unit. Apply solder to the short land sections before the flexible wire is disconnected from the connector on the CD servo board. (If theflexible wire is disconnected without applying solder, the CD pickup may

32、 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 strapSolderingCard wireCard wirePicup unitconnectorPicup unitconnectorCD ch

33、anger unitCD changer mechanism(No.MB080)1-5SECTION 2SPECIFIC SERVICE INSTRUCTIONSThis service manual does not describe SPECIFIC SERVICE INSTRUCTIONS.1-6 (No.MB080)SECTION 3DISASSEMBLY3.1Main body3.1.1Removing the metal cover (See Fig. 1)(1) Remove the three screws A attaching the metal cover onthe b

34、ack of the body.(2) Remove the six screws B attaching the metal cover on bothsides of the body.(3) Remove the metal cover from the body by lifting the rearpart of the cover.ONE POINTHow to eject the CD tray manually (see fig. 2)Turn the loading pulley gear at the bottom of the CD changerunit as show

35、n in Fig.2 and draw the CD tray toward the front.Fig.1Fig.23.1.2Removing the CD tray fitting (See Fig. 3) Prior to performing the following procedure, eject the CD tray.(1) After drawing the lower part of the tray fitting toward thefront, remove the five claws. Then, while moving the tray fit-ting u

36、pward, remove it.Fig.3Metal coverAB(both sides) Loading pulley gear(See fig.1)Joint ClawCD tray fitting(No.MB080)1-73.1.3Removing the CD changer unit (See Fig. 4 to 7) Prior to performing the following procedure, remove the metalcover and CD tray fitting.(1) Remove the card wire attached to CD chang

37、er unit on theadhesion tape.(2) Disconnect the card wire from the connector CW105 on theCD board.(3) Disconnect the harness from the connector CW104 on themain board.(4) Remove the two screws C attaching the CD changer unit tothe rear panel.(5) Remove the two screws D attaching the CD changer unit t

38、oboth sides of the front panel assembly.(6) Draw the CD changer unit upward from behind while pull-ing the rear panel outward.Fig.4Fig.5Fig.6Fig.7CD changer unitCard wireAdhesion tapeCW104CD boardCD changer unitMain boardCW105Rear panelCD(both sides)Rear panelCD changer unitFront panelassembly1-8 (N

39、o.MB080)3.1.4Removing the front panel assembly (See Fig. 8 to 10) Prior to performing the following procedure, remove the metalcover and CD changer unit.(1) Disconnect the card wire from the connector CW101 on themain board.(2) Disconnect the harness from the connector CW108,CW109 and CW110 on the m

40、ain board.(3) Remove the screw E fixiing the lug wire.(4) Remove the two screws F attaching the front panel assem-bly to both sides of the body.(5) Remove the screw G attaching the main board to the frontpanel assembly.(6) Remove the screw H attaching the front panel assembly tobottom of the body.(7

41、) Release the two joints1 and two joints2, and detach thefront panel assembly toward the front.Fig.8Fig.9Fig.10Main boardAmp. boardCW101CW109CW110CW108ACW1ACW2Front panelassemblyJoint1(both sides)F(both sides)E(fixing the lug wire)Joint1(both sides)F(both sides)Front panelassemblyGMain boardHJoint2(

42、No.MB080)1-93.1.5Removing the heat sink & amp. Board (See Fig. 8, 11 and 12) Prior to performing the following procedure, remove the metalcover and CD changer unit.(1) Disconnect the card wire from the connector ACW1 andthe harness from the connector ACW2 on the amp. board.(2) Remove the four screws

43、 I attaching the heat sink cover tothe rear panel. Remove the heat sink cover.(3) Remove the four screws J attaching the heat sink and twoscrews K attaching the speaker terminal to the rear panel.(4) After moving the heat sink upward, remove the claws. Thenpull out the heat sink & amp. board inward.

44、3.1.6Removing the tuner board (See Fig. 12 and 13) Prior to performing the following procedure, remove the metalcover.(1) Disconnect the card wire from the connector CON01 on thetuner board.(2) Remove the two screws L attaching the tuner board to therear panel.3.1.7Removing the rear panel (See Fig.

45、12) Prior to performing the following procedure, remove the metalcover, CD changer unit, heat sink & amp. board and tunerboard.(1) Remove the screw M and three screws N attaching the rearpanel.Fig.11Fig.12Fig.13Rear panelHeat sinkcoverIISpeakerterminal KLMRear panelHeat sink ClawsNJJMain boardTuner

46、boardCON01Rear panel1-10 (No.MB080)3.1.8Removing the main board (See Fig. 14) Prior to performing the following procedure, remove the metalcover, CD changer unit and rear panel.(1) Disconnect the card wire from the connector CW101 andthe harness from the connector CW108, CW109 andCW110 on the main b

47、oard.(2) Disconnect the harness from the connector PCW1 on thefuse board.(3) Remove the screw G attaching the main board to the frontpanel assembly. (See Fig.9)(4) Remove the two screws O attaching the heat sink to thebottom chassis.3.1.9Removing the power cord (See Fig. 14) Prior to performing the

48、following procedure, remove the metalcover, CD changer unit and rear panel.(1) Disconnect the power cord from the connector PW101 onthe power supply board and pull up the power cord stopperupward.Fig.143.1.10 Removing the power ICs (See Fig. 15 and 16) Prior to performing the following procedure, re

49、move the metalcover, CD changer unit and heat sink & amp. board.(1) Unsolder the power ICs solder points.(2) Remove the four screws P attaching the power ICs to theheat sink.Fig.15Fig.163.1.11 Removing the power transformer (See Fig. 17) Prior to performing the following procedure, remove the metalc

50、over, CD changer unit and heat sink & amp. board.(1) Disconnect the power cord from the connector PW101 onthe power supply board.(2) Disconnect the harness from the connector PCW1 on thefuse board.(3) Remove the four screws Q attaching the power transformeron the bottom chassis.Fig.17Power supplyboa