JVC-MXGT700-cs-sm维修电路原理图.pdf
SERVICE MANUAL COMPACT COMPONENT SYSTEM No.21079 Apr. 2002 COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD. MX-GT700 MX-GT700 Contents Safety Precautions Importance administering point on the safety Preventing static electricity Disassembly method Wiring connection Adjustment method Flow of functional operation until TOC read Maintenance of laser pickup Replacement of laser pickup Trouble shooting Description of major ICs 1-2 1-3 1-4 1-5 1-18 1-19 1-23 1-24 1-24 1-25 1-2841 Area suffix J - U.S.A. C - Canada DISC CHANGE COM P U PLAY CONTROL STANDBY/ON STANDBY CD-R/RW PLAYBACK TUNING CLOCK /TIMER DISPLAY PHONES REPEAT REC START / STOP CD REC STARTDUBBING PROGRAMRANDOM TAPE BTAPE A AUX TAPECD FM / AM SUBWOOFER LEVEL SOUND MODE MX-GT700 EXTENDED SUPER BASS CD3 FULL - LOGIC CONTROLCD SYNCHRO RECORDING CD 1 CD 2 CD 3 SP-MXGT700SP-MXGT700CA-MXGT700 DISC SKIP VOLUM E VOLUM E + RMSMXG500 A REMOTE CONTROL STANDBY/ON 123 456 789 10+10 SLEEP SOUND MODE TAPE A/B FADE M UTING FM /A M AUX CD TAPE SUBWOOFER LEVEL FM MODE RadioFans.CN 收音机爱 好者资料库 MX-GT700 1-2 1. 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 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. Good earth ground Place this probe on each exposed metal part. AC VOLTMETER (Having 1000 ohms/volts, or more sensitivity) 1500 10W 0.15 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. In regard with component parts appearing on the silk-screen printed side (parts side) of the PWB diagrams, the parts that are printed over with black such as the resistor ( ), diode ( ) and ICP ( ) or identified by the mark nearby are critical for safety. (This regulation does not correspond to J and C version.) RadioFans.CN 收音机爱 好者资料库 MX-GT700 1-3 Importance administering point on the safety Fuse board (Forward side)Power supply board (Forward side) 4A 125V 4A 125V RFS9 RFS2 Caution: For continued protection against risk of fire, replace only with same type 4A/125V for RFS2 and RFS9. This symbol specifies type of fast operating fuse. Precaution: Pour eviter risques de feux, remplacez le fusible de surete de et RFS2 et RFS9 comme le meme type que 4A/125V. Ce sont des fusibles suretes qui functionnes rapide. MX-GT700 1-4 Preventing static electricity 1. Grounding to prevent damage by static electricity Electrostatic 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. 2. About the earth processing for the destruction prevention by static electricity In the equipment which uses optical pick-up (laser diode), optical pick-up is destroyed by the static electricity of the work environment. Be careful to use proper grounding in the area where repairs are being performed. 2-1 Ground the workbench 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. 2-2 Ground yourself Use an anti-static wrist strap to release any static electricity built up in your body. 3. Handling the optical pickup 1. 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. 4. 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 strap Attention when CD mechanism assembly is decomposed 1. Remove the CD changer unit. 2. Remove the CD changer mechanism. 3. Solder is put up before the card wire is removed from the pickup unit connector on the CD mechanism assembly. (When the card wire is removed without putting up solder, the CD pick-up assembly might destroy.) 4. Please remove solder after connecting the card wire with the pickup unit connector when you install picking up in the substrate. *Please refer to Disassembly method in the text for pick-up and how to detach the CD mechanism assembly. Soldering Fig.1 Fig.2 Card wire Card wire Picup unit connector Picup unit connector CD changer unit CD changer mechanism MX-GT700 1-5 Remove the three screws A attaching the metal cover on the back of the body. Remove the six screws B attaching the metal cover on the both sides of the body. Remove the metal cover from the body by lifting the rear part of the cover. 1. 2. 3. Disassembly method Removing the metal cover (See Fig.1) ONE POINT How to eject the CD tray (see fig.2) Although it will end if the OPEN/CLOSE button is pushed when a power supply can be taken, when that is not right, CD tray will be opened manually. Turn the loading pulley gear at the bottom of the CD changer unit as shown in Fig.2 and draw the CD tray toward the front. Removing the CD Tray fitting (See Fig. 3) Prior to performing the following procedure, eject the CD tray. After drawing the lower part of the tray fitting toward the front, remove the five claws. Then, while moving the tray fitting upward, remove it. 1. Prior to performing the following procedure, remove the metal cover. Remove the card wire attached to CD changer unit on the adhesion tape. Disconnect the card wire from the connector CW107 on the CD servo board. Disconnect the harness from the connector RCW6 on the main board and CW105 on the CD servo board. Remove the two screws C attaching the CD changer unit to the rear panel. Remove the two screws D attaching the CD changer unit to the both side of front panel assembly. Draw the CD changer unit upward from behind while pulling the rear panel outward. 1. 2. 3. 4. 5. 6. Removing the CD changer unit (See Fig.4 to 7) Fig.1 Fig.2 Fig.3 Metal cover A B (both sides) Joint Claw CD tray fitting Loading pulley gear (See fig.1) Fig.4 CD changer unit Card wire Adhesion tape MX-GT700 1-6 Prior to performing the following procedure, remove the metal cover and the CD changer unit. Disconnect the card wire from the connector FCW3 on the main board. Disconnect the harness from the connector JCW1, JCW2 and HCW3 on the main board. Remove the two screws E attaching the front panel assembly to both sides of the body. Remove the screw F attaching the earth terminal extending from the cassette mechanism assembly. Remove the screw G attaching the main board to front panel assembly. Remove the screw H attaching the front panel assembly to the bottom of the body. Release the two joints1 and two joints2, and detach the front panel assembly toward the front. 1. 2. 3. 4. 5. 6. 7. Removing the front panel assembly (See Fig.8 to 10) Fig.6 Fig.7 Fig.5 RCW6 CD servo board CD changer unit Main board CW107 CW105 Rear panel C D (both sides) Rear panel CD changer unit Front panel assembly Fig.8 Fig.9 Main board Amp. board FCW3 JCW2 JCW1 HCW3 ACW1 ACW2 ACW5 Front panel assembly Joint1 (both sides) E (both sides) Joint1 (both sides) E (both sides) F (fixing the earth wire) Front panel assembly G Main board ACW6 1-7 MX-GT700 Prior to performing the following procedure, remove the metal cover and the CD changer unit. Remove the four screws I attaching the heat sink cover to the rear panel. Remove the heat sink cover. Remove the four screws J attaching the heat sink and two screws K attaching the speaker terminal to the rear panel. After moving the heat sink upward, remove the claws. Then pull out the heat sink & amp. board inward. 1. 2. 3. 4. Removing the heat sink & amp. board (See Fig.8, 11 and 12) Prior to performing the following procedure, remove the metal cover. Disconnect the card wire from the connector CON01 on the tuner board. Remove the two screws M attaching the tuner board to the rear panel. 1. 2. Removing the tuner board (See Fig.12 and 13) Prior to performing the following procedure, remove the metal cover and heat sink cover. Disconnect the harness from the connector ACW5 on the amp. board. Remove the two screws L attaching the fan motor to the rear panel. 1. 2. Removing the fan motor (See Fig.8 and 12) Prior to performing the following procedure, remove the metal cover, CD changer unit, heat sink & amp. board and tuner board. Remove the two screws N and three screws O attaching the rear panel. 1. Removing the rear panel (See Fig.12) Disconnect the card wire from the connector ACW1 and the harness from the connector ACW2 and ACW6 on the amp. board. Fig.10 H Joint2 (Bottom side) Fig.11 Fig.12 Fig.13 Heat sink Fan motor Speaker terminal K M N O L Main board Rear panel Tuner board CON01 J J Rear panel Rear panel Heat sink cover I I MX-GT700 1-8 Prior to performing the following procedure, remove the metal cover, CD changer unit and heat sink & amp. board. Remove the four screws Q attaching the power ICs to the heat sink. Unsolder the power ICs solder point. 1. 2. Removing the power ICs (See Fig.15 and 16) Prior to performing the following procedure, remove the metal cover, CD changer unit and rear panel. Disconnect the card wire from the connector FCW3 and the harness from the connector JCW1, JCW2 and HCW3 on the main board. Disconnect the harness from the connector PCW1 on the fuse board. Remove the screw G attaching the main board holder to the front panel assembly. (See Fig.9) Remove the two screws P attaching the heat sink to bottom chassis. 1. 2. 3. 4. Removing the main board (See Fig. 14) Removing the power cord (See Fig. 14) Prior to performing the following procedure, remove the metal cover, CD changer unit and rear panel. Disconnect the power cord from the connector RCW2 on the power supply board and pull up the power cord stopper upward. 1. Prior to performing the following procedure, remove the metal cover, CD changer unit and heat sink & amp. board. Disconnect the power cord from the connector RCW2 on the power supply board. Disconnect the harness from the connector PCW1 on the fuse board. Remove the four screws R attaching the power transformer and the screw S attaching the earth terminal on the bottom chassis. 1. 2. 3. Removing the power transformer (See Fig .17) Fig.16 Fig.17 Fig.15 Fig.14 Fuse board Power supply board Fuse board Power supply board Power cord Bottom chassis Power cord stopper P Q R S Heat sink Heat sink Amp. board FCW3 JCW2 RCW2 JCW1 HCW3 PCW1 Heat sink Power transformer Power ICs solder point Main