Jvc-THA-35-Service-Manual电路原理图.pdf

TH-A35TH-A35SERVICE MANUALDVD DIGITAL CINEMA SYSTEMContentsCOPYRIGHT © 2003 VICTOR COMPANY OF JAPAN, LTD. No. 22020Jun. 2003Safety precautions - 1- 2Preventing static electricity - 1- 3Important for laser products - 1- 4Disassembly method - 1- 5Description of major ICs - 1- 15Wiring connection - 1- 20Area SuffixJ . U.S.A.C . CanadaCOMPACTSUPER VIDEODIGITALSURROUND DIGITAL¥EXPRO LOGICVOLUMEPHONESDSPSORROUNDSOURCESTANDBYSTANDBY/ONTH-A351-2Warning!CAUTIONGood earth groundPlace this probe on each exposedmetal part.AC VOLTMETER(Having 1000 ohms/v1500 10Wolts,or more sensitivity)0.15 F AC TYPESafety Precautions1. 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 manufacturer's 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.circle6Plug 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.)circle6Alternate 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.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.TH-A351-3Preventing static electricityElectrostatic 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.1.1. Grounding to prevent damage by static electricityStatic electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD players.Be careful to use proper grounding in the area where repairs are being performed.1.1.1. Ground the workbench1. 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.1.1.2. Ground yourself1. Use an anti-static wrist strap to release any static electricity built up in your body.1.1.3. Handling the optical pickup1. 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.1.2. 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 strap1MTH-A351-41. CLASS 1 LASER PRODUCT2. CAUTION : Visible and invisible laser radiation when open and interlock 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. Important for laser productsREPRODUCTION AND POSITION OF LABELSCLASS 1 LABELWARNING LABEL5. 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.!CAUTION Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check. 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.CLASS 1LASER PRODUCTCLASS 1LASER PRODUCTTH-A351-52. PIN CONFIGURATIONDisassembly methodsquare6Removing the cabinet topsquare6Removing the tray Doorsquare6Removing the cabinet frontsquare6Removing the TUNER and panel rearsquare6Removing the MPEG BOARDsquare6Removing the MAIN BOARDsquare6Removing FANsquare6Removing the Thermal - Regifersquare6Removing the VCD mechanism base assemblysquare6Removing PWB, AMPsquare6Removing Power , fruformersquare6Removing the FRONT PWB & LED PWBCommence disassembly of this set by removing the main units and then proceed to the components and assemblies inside the units.TH-A351-6square6 Removing the cabinet top (See Fig.1)1. Unscrew the 6 serew A 2. Lift the cabinet top by holding the two sides of it,while moving it upward and backward.square6 Removing the Tray Door(See Fig.2)1. Eject the disc tray.(Rotate the screw B counter - clockwise if no supply)2. Lift up the tray door in the indicated directionFig.1CLASS 1LASER PRODUCTRight coverLeft coverTop coverRear coverFig.2BTH-A351-7Fig.3Fig.4Fig.5square6 Removing the cabinet front(See Fig.3)Caution You must ensure the TRAY door isn't it's place before you remove the panel front from body.1. Unscrew the serew 2 C & 2 D.2. Pull the panel front toward yourself while pressing 5 stoppers to disengage.square6 Removing the TUNER and panel rear (See Fig.4)1. Unserew the screw H form mpeg board unit and unitand main board unit. 2. Unserw the screw K form body.3. Take the supply cord out of panel rear.4. Remove teh panel rear with tuner .square6 Removing the MPEG BOARD (See Fig.5)Caution Mpeg board may be taken out only when thepanel rear and Tunet have been taken away.1. Pull the cable connetor mpeg board.2. Unscrew the screw M.3.Separate the mpeg board from main boardvertically.DCSTOPPERSTOPPERSTOPPERSTOPPERSTOPPERCDMCLASS 1LASER PRODUCTHKTH-A351-8square6 Removing the MAIN Board( See Fig.6 & 7 )Caution Main board may be taken out when the mpeg board has been taken away.1. Force the PCB spacer Q to exit the holes of main board.2. Unscrew the screw P.3.Unscrew the screw R then you can remove the main board with heat sink.4.Untie or open connecters to power transformer, PWB,AMP, DVD - mech.square6 Removing FAN(See Fig.8)1.Unscreew 3 screws R with HOLDER, pull out connector from PWB, main.2.Unscrew 2 screws S from HLDR.square6 Removing the Thermal - Regifer(See Fig.9)1.Unscreew the screws though power IC and thermal- HOLDER.2.Pull wire of thermal - register from PWB main.PQFig. 6Fig. 7Fig. 9Fig. 8RSPULLTH-A351-9square6 Removing the CD mechanism base assembly(See Fig.10)square6Prior to performing the following procedure, remove the cabinet front assembly.1. Disconnect the harnesses from connector CN191 and CN192 on the main board and release them from the cord stopper respectively.2. Remove the four screws M attaching the transformer assembly.square6 Removing PWB,AMP(See Fig.11)1. Unscrew 4 screws L.2. Pull out connecter from PWB, AMP.square6 Removing Power, frusformer(See Fig.11)1. Unscrew 4 screws N2. Untie wire connecter to PWB, MAIN.Fig. 11Fig. 10TH-A351-10square6 Removing the front PWB & Led, PWB (See Fig.12-13)square6Prior to performing the following procedure, remove the front panel assembly.1. Remove the seven screws X and 3 screws attaching the front panel board inside the front panel assembly.2. Push out KNOB, VOLUME through PWB, FR.Fig. 13Fig. 12