Kenwood-DMCJ7R-md-sm 维修电路原理图.pdf

GeneralPower sourceDC .3.6 V (rechargeable lithium-ionbattery NB-L10A x 1)DC 5 V (AC adaptor)AC 230 V, 50 HzDC 3 V Separately available battery case(commercially available, AAsize, alkaline battery x 2)DC 4.0 V : Separately available caradaptor, DC-C70(for cars with a 12-24 V DCnegative earth electrical system)Power consumption7 W (AC adaptor)Output powerRMS; 20 mW (10 mW + 10 mW)(0.2 % T.H.D.)Charging timeApprox. 3.0 hours(When using the AC adaptor includedwith the unit)Battery lifeNote:The battery case is only sold in certain areas. For more details,please ask your dealer.The continuous recording time is for analogue input when thevolume level is set to VOL 0.The continuous play time shows the value when the volume level isset to VOL 15.The above values are the standard values when the unit is chargedand used at an ambient temperature of 20oC.The operating time when using alkaline batteries may be different,depending on the type and manufacturer of the batteries, and onthe operating temperature.Input sensitivityOutput levelDimensionsWidth: 87.0 mm (3-7/16)Height: 29.4 mm (1-3/16)Depth: 81.5 mm (3-7/32)Weight219 g (0.49 lbs.) with rechargeablebatteryInput socketLine/optical digital, microphone (powered by the main unit)Output socketHeadphones (impedance: 32ohms)/remote control unit MiniDisc RecorderTypePortable MiniDisc recorderSignal readoutNon-contact, 3-beam semi-coductorlaser pick-upAudio channelsStereo 2 channels/monaural (long-play mode) 1 channelFrequency response20 - 20,000 Hz ( 3 dB)Rotation speedApprox 400 - 900 rpmError correctionACIRC (Advanced Cross InterleaveReed-Solomon Code)CodingATRAC (Adaptive TransformAcoustic Coding), 24-bit computed typeRecording methodMagnetic modulation overwrite methodSampling frequency44.1 kHz (32 kHz and 48 kHzsignals are converted to 44.1 kHz,and then recorded.)Wow and flutterUnmeasurable (less than 0.001% W.peek)Continuous recording:Approx. 4.5 hoursContinuous recording:Approx. 4 hoursContinuous recording:Approx. 8.5 hoursContinuous play:Approx. 6.5 hoursContinuous play:Approx. 8 hoursContinuous play:Approx. 14.5 hoursHeadphones10 mW +32 ohms10 mWLINE300mV (-12dB)50 k ohmsMaximumoutput levelSpecified outputRecording levelReference input levelInput impedanceMIC H0.25 mV10 k ohmsMIC L2.5 mV10 k ohmsLINE100 mV20 k ohmsLoadimpedanceWhen using two,commercially available,high capacity, AA size,alkaline batteries (in theseparately available batterycase)When using the recharge-able battery NB-L10A (fullycharged) included with theunitWhen using two, commerciallyavailable, high capacity, AAsize batteries with therechargeable battery (fullycharged).DIGITAL EDIT & RECORDINGRECORDINGREC LEVEL/CURSORCHARACTERAUTO MARKSYNC/F.PLAYVOLUME/NAMEPORTABLE MD RECORDER DMC-J7RBASS/DELETE MODE/INSERTOPENDISPEDITOFFENTEREJECTPORTABLE MD RECORDERDMC-J7RSERVICE MANUAL 1998-6/B51-5441-00 (K/K) 3163Transparency cover *(B10-)Knob(K29-2270-08)Bottom cabinet *(A02-)Front cabinet(A02-2808-08)MD cover(F07-1638-08)Knob(K27-2272-08)Upper case assy(A02-2814-08) : S(A02-2862-08) : BKnob base(A02-2816-08)* Refer to parts list on page 26. S: Silver, B: BlueIn compliance with Federal Regulations, following are reproduc-tions of labels on, or inside the product relating to laser productsafety.KENWOOD-Crop. certifies this equipment conforms to DHHSRegulations No. 21 DFR 1040. 10, Chapter 1, Subchapter J.DANGER : Laser radiation when open and interlock defeated.AVOID DIRECT EXPOSURE TO BEAMSPECIFICATIONSDMC-J7R(K) COVER1,1P( 98.11.30 1:44 PM yW 2RadioFans.CN 收音机爱 好者资料库DMC-J7R2CONTENTS / ACCESSORIES / CAUTIONSSPECIFICATIONS .Top coverCONTENTS / ACCESSORIES / CAUTIONS.2CONTROLS .3DISASSEMBLY FOR REPAIR.4BLOCK DIAGRAM .6CIRCUIT DESCRIPTION.7TROUBLE SHOOTING.8NOTE ON SCHEMATIC DIAGRAM.14PARTS DESCRIPTIONS .15WAVEFORMS OF MD CIRCUIT .16PC BOARD .17SCHEMATIC DIAGRAM .21EXPLODED VIEW .24PARTS LIST.26ContentsAccessoriesRemote control (1)(A70-1210-08)Stereo headphone (1)(W01-0941-05) : K,P type(W01-0948-05) : T,E,E1,M typeRechargeable battery (1)(W03-5946-08): NB-L10AAC adapter (1)(W08-0669-08) : M type(W08-0672-08) : E,E1 type(W08-0673-08) : T type(W08-0674-08) : K,P typeAC plug adapter (1)(E03-0115-05) : M typeConnecting cord (1)(E30-2836-08)Carrying case (1)(W01-0955-08) How to resetWhen this product is subjected to strongexternal interference (mechanical shock,excessive static electricity, abnormal sup-ply voltage due to lightning, etc.) or if it isoperated incorrectly, it may malfunction. Ifsuch a problem occurs, do the following:1. Unplug the AC adaptor from the ACsocket.2. Remove the battery. 3. Leave the unit completely unpoweredfor approximately 30 seconds. 4. Plug the AC adaptor back into the ACsocket and retry the operation.If strange sounds, smell or smoke comeout of the unit or an object is dropped intothe unit, remove the AC adaptor from theAC socket immediately and contact an au-thorized KENWOOD service centre.CautionsDMC-J7R(K) COVER1,1P( 98.11.30 1:44 PM yW 3RadioFans.CN 收音机爱 好者资料库Error messagesMeaningRemedyBATT EMPTYThe battery run down.Charge the rechargeable battery or replace the alkaline batteries (or use the AC adaptor for power).BLANK DISCNothing is recorded.Replace the disc with a recordeddisc.Cant COPYNo copy can be made because ofthe SCMS copyright system.Record using the analogue cable.Cant EDITA track cannot be edited.Change the stop position of thetrack and then try editing it.Cant RECRecording cannot be performedcorrectly due to vibration or shockin the unit.Re-record or replace it with another recordable disc.Cant WRITEEditing is impossible.Check the number of tracks.DEFECTThe disc is scratched. If the sound you hear is not right, try recording again.Replace the disc with anotherrecordable disc.Din UNLOCKPoor connection of the digital cable.Connect the digital cable securely.DISC ERRORThe disc is damaged.Reload the disc or replace it.DISC FULLThe disc is out of recording space.Replace it with another recordabledisc.HOLDThe unit is in the safety mode.Return the HOLD switch to itsoriginal position.LOCKEDLOCK ERRORThe EJECT lever was movedduring recording or editing.Turn off the power and remove theMiniDisc.NO DISCA disc has not been loaded.Load a disc.PB DISCPROTECTEDThe disc is write protected.You tried to record on a playback-only disc.Move the write protection knobback to its original position.Replace it with a recordable disc.POWER ?Improper power is being supplied.Use one of the specified powersources.SORRYSince a track number is currentlybeing located or written to, the unitcannot accept your command.Wait for a while and try the operation again.SYSTEM ERRYou have come to the conclusionthat the unit is out of order.To have it repaired, go to thedistributor where you purchased theunit.TEMP OVERThe temperature is too high.Turn off the power, and wait for awhile.TOC ERRORA large portion of the disc has beendamaged.Replace it with another recordeddisc.TOC FULLThere is no space left for recordingcharacter information (track names,disc names, etc.).Replace it with another recordabledisc.Tr. ProtectThe track has been protected frombeing erased.Edit the track with the device onwhich it was recorded.U TOC ERRORA large portion of the disc has beendamaged.There is an error in the recordedsignal.Replace it with another recordeddisc.Erase all of the signal errors, and then try recording again.? DISCA disc which contains data otherthan music was played.There is an error in the signal fromthe disc.A disc which contains non-musicdata cannot be played.Replace it with another recordeddisc.ERROR MESSAGESDMC-J7R3CONTROLS Main Unit 1. Monaural Long-Play Mode Indicator 2. Record Indicator 3. Level Meter 4. Repeat Indicator: 5. TOC Indicator 6. Battery Indicator: 7. Random Indicator 8. Track Number Indicator 9. Character/Time Information Indicator10. Synchro Recording Indicator11. Disc Mode Indicator12. Disc Name Indicator13. Track Name Indicator14. Remaining Recording Time Indicator15. Total Track Number Display16. Record/Track Mark Button17. Volume/Name Select Buttons: +, -18. Display/Lowercase Characters Button19. Character Button20. Stop/Power Off/Charge Button: /OFF21. Play/Pause Button:22. Fast Reverse/Fast Forward/Record-ing LevelControl/Cursor Buttons: /23. Enter/Fast Play/Synchro Button24. Edit/Auto Mark/Time Mark Button25. Eject Lever26. Bass/Delete Button27. Mode/Insert Button28. Microphone Input Socket29. Hold Switch30. Rechargeable Lithium-Ion BatteryCompartment31. Optical/Line Input Socket32. Headphones Socket33. 5V DC Input Socket34. Battert Case Connection Terminals123 4567891011121314151617 18 19 20 212223 24 25 26 2729343033283132 Remote Control Unit 1. Synchro Recording Indicator 2. Character/Time Information Indicator 3. Record Indicator 4. Repeat Indicator: 5. Random Indicator 6. Disc Mode Indicator 7. Total Track Number Display 8. Track Number Indicator 9. Battery Indicator:10. Headpones Socket11. Hold Switch12. Play Mode Button13. Volume Buttons: +, -14. Bass Button15. Display Button16. Play/Pause Button:17. Stop/Power Off Button:18. Fast Reverse/Fast Forward Buttons: /RANDOMTOTAL1RECSYNC121314111516171810162345789NAMES OF CONTROLS AND INDICATORS A rechargeable lithium-ion battery isthe only kind that can be used.Even if the battery supplied with theunit is not used, you should charge itat least once every three monthsbecause of the special quality of thisbattery. The rechargeable battery can becharged approximately 300 times. Do not use any battery other thanthat specified. Use of other batter-ies maycause malfunctions. When the operating time is reducedto about half the normal amount oftime, even after a full charge is per-formed, replace the battery with anew one. When charging or when using therechargeable battery, use it withinan ambient temperature range of5C to 35C. If the rechargeable battery is used ina cold environment, the operatingtime will decrease.Since the rechargeable battery isvulnerable to damage, please notethe following. Do not carry the battery in yourpocket or a bag together with metalobjects (keys, coins, jewelry, etc.).The battery may short out and gen-erate significant amounts of heat. Do not short-circuit the terminals asthey will become very hot and willdamage the battery. Do not dip the battery in water, donot dispose of it in a fire, and do nottake it apart.To avoid damaging the battery andshortening its service life, pleasenote the following. Do not drop or subject the battery toshock. Do not insert objects (metal etc.)into the battery compartment of thisproduct or into the rechargeable bat-tery. Do not get the terminals dirty.If the rechargeable terminals aredirty, the operating time may beshortened or it may not be possibleto charge the battery. After the rechargeable battery ischarged or used, it will get slightlywarm. This is normal.7 Notes about the rechargeable batteryDMC-J7R(K) COVER1,1P( 98.11.30 1:44 PM yW 6DMC-J7R4DISASSEMBLY FOR REPAIR1Bottom Cabinet1. Open the battery Lid.8-12. Screw .(A1) x62Top Cabinet1. Screw .(B1) x48-12. Flat Cable .(B2) x23Main PWB1. Screw . (C1) x28-22. Flat Cable .(C2) x34Mechanism Unit1. Lift the left side, and remove8-3in the arrow direction.Caution on DisassemblyFollow the below-mentioned notes when disassemblingthe unit and reassembling it, to keep it safe and ensureexcellent performance:1. Take the battery and minidisc out of the unit.2. When disassembling the machine, be sure to withdrawthe power plug from the socket in advance.3. When disassemble the parts, remove the nylon band orwire holder as necessary. To assemble after repair, be sure to arrange the wires asthey were. If a screw of different length is fitted to the MD mecha-nism (the screw of the part to be fitted to the MDmechanism chassis), it may contact the optical pickup,resulting in malfunction.4. When repairing, pay due attention to electrostatic chargesof IC.REMOVALPROCEDURESTEPFIGUREBottom CabinetTop CabinetCenterCabinetPull(A1)x11.4x2mm(A1)x11.4x2mm(A1)x21.4x2mm(A1)x21.4x2mm(B1)x11.4x2mm(B1)x11.4x2mm(B1)x21.4x2mmFigu re 8-1Figure 8-2Mechanism UnitFigure 8-3Caution:1. Handle carefully the main PWB and flexible PWB. After removing the flexible PWB (*1) for optical pickup fromthe connector, wrap the front end of flexible PWB in conduc-tive aluminum foil so as to protect the optical pickup fromelectrostatic damage.2. When removing the mechanism from the cabinet or wheninstalling it, it is advisable to rotate the unit lock plate to lower the holder section.(C1)x11.7x2.5mm(C1)x11.7x2.5mmPullPullPullPullPullPullPullPull(B2)x1(B2)x1(C2)x1(C2)x1(C2)x1Main PWBDMC-J7R(K) COVER1,1P( 98.11.30 1:44 PM yW 7DMC-J7R5DISASSEMBLY FOR REPAIRRemove the mechanism according to the disassembling meth-ods 1 to 3. (See Page 8.)How to remove the spindle motor (See Fig. 9-1.)1. Remove the solder joint (A1) x 1 of flex PWB.2. Remove the stop (A2) x 3 pcs. and remove the spindlemotor.Figure 9-5Flexible PWBsolder joint(A1) x1Spindle Motor(A2)x31.4x2.8mmMDMechanismFigure 9-1(B1)x2Remove the solder jointStop Washer(B2)x1Drive Gear(B3)x1Lift Motor(B4)x11.4x2.2mmFigure 9-2Figure 9-3(E1)x11.7x2.5mmShaftPickup UnitHow to reinstall the optical pickup unit(See Fig. 9-5.)1. Remove the screws (E1) x 1 pcs.2. Remove the soldering joint (C2) x2 places of flex PWB, andremove the sled motor.How to remove the magnetic head(See Fig. 9-4.)1. Remove the screw (D1) x 2 pc.2. Remove the screw (D2) x1 which connects the magnetichead to the head relay flex PWB, and remove the solderingjoint (D3) x2 pcs.Note:Mount carefully so as not to damage the magnetic head.(D1)x21.4x1.8mm(D1)x11.4x1.5mmPickup UnitMagnetic HeadSolderjoint(D3)x2Figure 9-4How to remove the lift motor (See Fig. 9-2.)1. Remove the solder joint (B1) x 2 of slide motor lead wire.2. Remove the stop washer (B2) x 1 pc., and remove the drivegear (B3) x 1 PC.3. Remove the screw (B4) x 1, and remove the lift motor.Note:Take care so that the motor gear is not damaged.(If the gear is damaged, noise is raised in search mode.)How to remove the sled motor (See Fig. 9-3.)1. Remove the solder joint (C1) x 2 of slide motor lead wire.2. Remove the screw (C2) x 2, and remove the sled motor.Note:Take care so that the motor gear is not damaged.(If the gear is damaged, noise is raised in search mode.)(C1)x21.4x1.2mmSled MotorWasher x2(C2)x2Mecha Flexible PWBsolder joint DMC-J7R(K) COVER1,1P( 98.11.30 1:44 PM yW 10DMC-J7R6BLOCK DIAGRAM LASERHEADLIFTMOTORMOTORDRIVERSPINDLEMOTORSLEDMOTORSPINDLEMOTORDRIVER(BA6965FV)VCC VSHEADDRIVERVSVCCRF SIGNALPROCESSOR(IR3R55)PICK COILDRIVERVCC VM4 MD-RAM(IC202)ENDECATRAC(LB37648B)SYSTEMMICROCOMPUTERE2-PROMDISPLAY UNITOPERATION UNITAD/DACONVERTERPOWERDRIVER2.5V REGULATOR+2.8V-2.8V(IR3M09)VCCPOWER DRIVER(IR3M09) 2.5V REGULATOR(ON/OFF)(IR3R54N)AUDIO AMP.VCC VEE(IR3R54N)AUDIO AMP.VCC VEE+68DC INRIPPLEFILTERDIGITAL INPUTOPTICALINPUT UNITLINE INPUTLINE OUTMIC INHEAD PHONES4.5VREGULATOR(ON/OFF)REMOTE CONTROLPOWER SELECTN-ch MOS FET3VDC/DCONVERTERBATTERYVOLTAGEREGULATORCONSTANTCURRENT DRIVERECHARGEABLEBATTERYOPICPOWER SELECTCHA