JVC-MXGA77-cs-sm维修电路原理图.pdf

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1、SERVICE MANUAL COMPACT COMPONENT SYSTEM No.22083 Jul. 2003 COPYRIGHT 2003 VICTOR COMPANY OF JAPAN, LTD. MX-GA77 MX-GA77 Contents Safety Precautions Important for laser produbts Preventing static electricity Disassembly method Wiring connection Adjustment method Flow of functional operation until TOC

2、 read Maintenance of laser pickup Replacement of laser pickup Trouble shooting Description of major ICs 1-2 1-4 1-5 1-6 1-19 1-20 1-24 1-25 1-25 1-26 1-3044 Area suffix B - U.K. E - Continental Europe EN - Northern Europe EV - Eastern Europe SP-MXGA77SP-MXGA77CA-MXGA77 CD 1 DISC CHANGE DISPLAY CD 2C

3、D 3 TUNING RANDOM PROGRAM DUBBING REC START / STOP CD REC START SET CLOCK / TIMER CANCEL / DEMO SOUND TURBO TAPE A / B REPEAT PHONES TUNING C 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 7 7 R O C K P O P CLASSIC D A N C E H A L L STADIUM S O U N D M O D E V O L U M E EJECTEJECT SUBWOOFER LEV

4、EL PRESET BEEP ECO STANDBY DISPLAY MODERDS MODESELECT MP3 RadioFans.CN 收音机爱 好者资料库 MX-GA77 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 aut

5、horized 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

6、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

7、. 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 L

8、ist 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

9、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 a

10、nd 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 isol

11、ation 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

12、 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.). A

13、lternate 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. Mea

14、sure 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 meas

15、urement. 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 maintaine

16、d. 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

17、 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-s

18、creen 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 1-3 MA-GA77 1. S

19、ervice should be performed by qualified personnel only. 2. This equipment has been designed and manufactured to meet international safety standards. 3. It is the legal responsibility of the repairer to ensure that these safety standards are maintained. 4. Repairs must be made in accordance with the

20、relevant safety standards. 5. It is essential that safety critical components are replaced by approved parts. 6. If mains voltage selector is provided, check setting for local voltage. 1. This design of this product contains special hardware and many circuits and components specially for safety purp

21、oses. 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. 2. Any unauthorised design alterations or additions will void the manufacturers guarantee ; f

22、urthermore the manufacturer cannot accept responsibility for personal injury or property damage resulting therefrom. 3. Essential safety critical components are identified by ( ) on the Parts List and by shading on the schematics, and must never be replaced by parts other than those listed in the ma

23、nual. Please note however that many electrical and mechanical parts in the product have special safety related characteristics. These characteristics are often not evident from visual inspection. Parts other than specified by the manufacturer may not have the same safety characteristics as the recom

24、mended replacement parts shown in the Parts List of the Service Manual and 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 shar

25、p 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. ! Burrs formed during molding may be left over on some parts of the

26、chassis. Therefore, pay attention to such burrs in the case of preforming repair of this system. (U.K only) MX-GA77 1-4 Important for laser products 1.CLASS 1 LASER PRODUCT 2.DANGER : Invisible laser radiation when open and inter lock failed or defeated. Avoid direct exposure to beam. 3.CAUTION : Th

27、ere 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 laserradiation and is equipped with safety switches whichprevent emission of radiation when the drawer is open

28、 and the safety interlocks have failed or are de feated. 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 haz

29、ardous radiation exposure. REPRODUCTION AND POSITION OF LABELS WARNING LABEL !CAUTION Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check. CLASS 1 LASER PRODUCT 1-5 MA-GA77 Preventing static electricity 1. Grounding to prevent damage by stat

30、ic 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 p

31、revention 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 b

32、y 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 mainta

33、in 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 opti

34、cal 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,

35、 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 bre

36、ak 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 u

37、nit. 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 car

38、d 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

39、mechanism MX-GA77 1-6 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 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 c

40、over (See Fig.1) ONE POINT How to eject the CD tray manually (see fig.2) 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

41、. 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 and CD tray fitting. Remove the card wire attached to CD changer unit on the adhes

42、ion tape. Disconnect the card wire from the connector CW105 on the CD board. Disconnect the harness from the connector CW104 on the main 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 both sides of the front pa

43、nel 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 Ad

44、hesion tape 1-7 MA-GA77 Prior to performing the following procedure, remove the metal cover and CD changer unit. Disconnect the card wire from the connector CW101 on the main board. Disconnect the harness from the connector CW108, CW109 and CW110 on the main board. Remove the screw E fixiing the lug

45、 wire. Remove the two screws F attaching the front panel assembly to both sides of the body. Remove the screw G attaching the main board to the front panel assembly. Remove the screw H attaching the front panel assembly to bottom of the body. Release the two joints1 and two joints2, and detach the f

46、ront 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 CW104 CD board CD changer unit Main board CW105 Rear panel C D (both sides) Rear panel CD changer unit Front panel assembly Fig.8 Fig.9 Main board Amp. board CW101 CW109 C

47、W110 CW108 ACW1 ACW2 Front panel assembly Joint1 (both sides) F (both sides) Joint1 (both sides) F (both sides) E(fixing the lug wire) Front panel assembly G Main board MX-GA77 1-8 Prior to performing the following procedure, remove the metal cover and CD changer unit. Disconnect the card wire from

48、the connector ACW1 and the harness from the connector ACW2 on the amp. board. 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. Afte

49、r moving the heat sink upward, remove the claws. Then pull out the heat sink leave all servicing to qualified service personnel. Caution switch! Disconnect the mains plug to shut the power off completely. The switch in any position does not disconnect the mains line. The power can be remote controlled. Caution: Proper Ventilation To avoid risk of electric shock and fire, and to prevent damage, locate the appa