Jvc-XMPX-50-WT-Service-Manual电路原理图.pdf

SERVICE MANUALPORTABLE MINIDISC PLAYERNo.20902Jan. 2001COPYRIGHT 2001 VICTOR COMPANY OF JAPAN, LTD.XM-PX50WTXM-PX50WTArea Suffix UB Hong KongContentsSafety PrecautionsImportant for laser productsAttention whenMD pick up is exchangedDisassembly methodAdjustment methodMaintenance of laser pickupReplacement of laser pickupDescription of major ICs1-21-31-41-51-111-121-121-1325XM-PX50WT1-21. 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 methodPlug 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.). 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 groundPlace this probe on each exposedmetal part.AC VOLTMETER(Having 1000 ohms/volts,or more sensitivity)1500 10W0.15 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.XM-PX50WT1-3Important 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 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 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 laserstrålning är denna del är öppnad och spårren är urkopplad. Betrakta ej strålen.VARO : Avattaessa ja suojalukitus ohitettaessa olet alttiina näkymättömälle lasersäteilylle.Älä katso säteeseen.ADVARSEL : Usynlig laserstråling ved åbning , når sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling.ADVARSEL : Usynlig laserstråling ved åpning,når sikkerhetsbryteren er avslott. unngå utsettelse for stråling.REPRODUCTION AND POSITION OF LABELSWARNING LABELDANGER : Invisibie laser radiation when open and interlock or defeated.AVOID DIRECT EXPOSURE TO BEAM (e)VARNING : Osynlig laserstrålning är denna del är öppnad och spårren ärurkopplad. Betrakta ej strålen. (s)VARO : Avattaessa ja suojalukitus ohitettaessa olet alttiina näkymättömälle lasersäteilylle.Älä katso säteeseen. (d)ADVARSEL :Usynlig laserstråling ved åbning , når sikkerhedsafbrydere er ude af funktion. Undgå udsættelse for stråling. (f)!CAUTIONPlease use enough caution not to see the beam directly or touch it in case of an adjustment or operationcheck.XM-PX50WT1-4The laser diode in the traverse unit (optical pick up) is easy to be destroyed by clothes and the human body to the electrified static electricity.Please note the explosion by static electricity when repairing.In the equipment which uses an optical pick up (laser diode), an optical pick up is destroyed by the static electricity of the work environment. Please do the earth processing and work.2. About the earth processing for the electrostatic destruction prevention1) Earth of work standPlease pull the conductive material (conductive sheet) or the iron plate to the depository place of the traverse unit (optical pick up), and take the earth to ground.2) Human body earthPlease use the anti-static wrist strap to exhaust the electrified static electricity to the human body.3. Handling the optical pick up1) Please return according to a correct procedure based on short processing after exchangingparts. 2) Do not use a tester to check the condition of the laser diode in the optical pick up .The tester 's internalpower source can easily destroy the laser diode. 4. Attention when unit is disassembledPlease refer to “Disassembling method“ for how to detach .Conductive material (conductive sheet) or the iron plateanti-static wrist strapAttention when MD pickup is exchanged1. About the static electricity protection measuresSolder short1) Please be sure to solder before a flexible wire is removed from connector on a main printed circuit board as shown. if you removes without soldering.the MD picking up assembly might destroy2) When installing , solder in the part of short round should be removed after a flexible wire is connected with connector.XM-PX50WT1-5Shift the door lever to open the door.Remove the four screws A and detach the MD door assembly from the main body.1.2.Disassembly methodRemoving the MD door assembly (See Fig.1 and 2)Prior to performing the following procedure, remove the MD door assembly.Turn the Holder assembly as shown in Fig.3.Pull the side arm (L) marked a and remove outward. Open the Holder assembly as shown in Fig.4. Move the “U-shaped” notch marked b in the direction of the arrow and release it from the shaft.Move the part c inward and pull out the Holder assembly from the shaft.1.2.3.4.Removing the holder assembly (See Fig.3 and 4)When reassembling, first reattach the part c to the shaft of the Chassis assembly. And next, fit the “U-shaped” notch to the shaft.ATTENTION: MD door assemblyDoor leverAAFig.1Fig.2Fig.3Part aPart b”U-shaped” notchPart c ShaftSide arm (L)MD door assemblyDoor leverHolder assemblyHolder assemblyHolder assemblyPart cHolder assemblyFig.4XM-PX50WT1-6Prior to performing the following procedure, remove the MD door assembly and the holder assembly.Open the battery lid. Release the tab d and pull out the battery lid.Remove the screw B and pull out the side arm (R) upward.Remove the two screws C and pull out the eject unit.Remove the screw D, E, F and G attaching the chassis assembly respectively.Disengage the three joints e of the bottom case and the battery holder. Remove the chassis assembly and the jack cover at once.1.2.3.4.5.Removing the chassis assembly (See Fig.5 to 7)Chassis assemblySide arm (R)Battery lidTab dJoint eBCEject unitCGDFEBottom caseBattery holderJoints eBattery lidChassis assemblyFig.5Fig.6Fig.7Chassis assemblyJoint eJoints eXM-PX50WT1-7Solder the short circuit round of the flexible wire on the main board.Disconnect the flexible wires from connector CN301 and CN401 on the main board.Remove the one screw H attaching the main board. Remove the main board with the battery holder .Unsolder the four soldered parts f retaining the main board and the battery holder.1.Removing the main board and the battery holder (See Fig.8 and 9)Prior to performing the following procedures, remove the MD door assembly, the holder assembly and the chassis assembly.Prior to performing the following procedures, remove the MD door assembly, the holder assembly, chassis assembly and the main board.Disconnect the flexible wire extending from the headphone jack from connector CN601 on the main board.1.When reassembling, connect the flexible wire extending from the pickup to the connector on the main board and unsolder the short circuit round.ATTENTION: Before disconnecting the flexible wire extending from the pickup, make sure to solder the short circuit round to prevent damage to the pickup.ATTENTION: Removing the headphone jack assembly (See Fig.10)Soldering fBattery holderHCN401CN301Headphone jack assemblyMain boardBattery holderHeadphone jack assemblyCN601CN401CN301Fig.8Fig.9Fig.10Soldering fShort circuitroundShort circuit roundMain boardXM-PX50WT1-8Unsolder the part g on the flexible wire extending from the underside of the Chassis assembly to the spindle motor.1.Remove the three screws I attaching the spindle motor.2.Removing the spindle motor (See Fig.11)Remove the slit washer and the worm gear from the underside of the Chassis assembly.Remove the screw J attaching the shaft holder and draw out the shaft (lead screw).Pull out the Pickup unit and the lead screw while disengaging the part h and i.1.2.3.Removing the pickup unit (See Fig.11)Prior to performing the following procedures, remove the MD door assembly, the holder assembly, the chassis assembly and the main board.Do not spill flux on the gear and others.ATTENTION: When handling the Pickup unit, touch the parts marked in Fig.13 only.ATTENTION: Remove the screw K and the lead spring.Pull out the shaft from the pickup.1.2.Removing the pickup (See Fig.12 and 13)When handling the pickup unit, touch the parts marked in Fig.13 only.ATTENTION: Lead screwKLead springTouch these parts only.Worm gearSlit washerIJShaft holderSpindle motorSoldering gPart hPart iChassis assemblyFig.11Fig.12Fig.13Pickup unitPickupXM-PX50WT1-9Peel off the adhesive tape j on the flexible wire on the underside of the feed motor.Unsolder soldering k connecting the flexible wire to the feed motor.Remove the two screws L attaching the feed motor.1.2.3.Removing the feed motor (See Fig.14)When reassembling, reattach the flexible wire with an adhesive tape andsolder.ATTENTION: Chassis assemblyFeed motorjSoldering kLPickup unitLFig.14XM-PX50WT1-10Remove the four screws A on the bottom of the body.Remove the top cover upward while pushing the front part a. Pull out the charge board from the bottom cover.1.2.Removing the charge board (See Fig.1 to 3)Fig.1Fig.2Fig.3AAAATop coverPart aPushCharge boardBottom cover