JVC-MXK50-cs-sm维修电路原理图.pdf

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1、SERVICE MANUAL COMPACT COMPONENT SYSTEM No.21121 Nov. 2002 COPYRIGHT 2002 VICTOR COMPANY OF JAPAN, LTD. MX-K50 MX-K50 Contents Safety Precautions Preventing static electricity Important for laser products Disassembly method Wiring connection Adjustment method Flow of functional operation until TOC r

2、ead 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 1-2843 Area suffix UW - Brazil,Mexico,Peru U - Other Areas SP-MXK50SP-MXK50CA-MXK50 DISC CHANGE COM P U PLAY CONTROL STANDBY/ON STANDBY CD-R/RW PLAYBACK

3、 TUNING CLOCK /TIMER DISPLAY PHONES REPEAT REC START /STOP CD REC STARTDUBBING PROGRAMRANDOM TAPE BTAPE A TAPECD FM /AM ACTIVE BASS EX. LEVEL SOUND MODE MX-K50 CD 2 CD 3 ACTIVE BASS EXTENSION CD3 FULL - LOGIC CONTROLCD SYNCHRO RECORDING AUX CD 1 DISC SKIP VOLUME VOLUME + STANDBY/ON 123 456 789 10+10

4、 SLEEP ACTIVE BASS EX. LEVEL SOUND MODE FM MODE TAPE A/B KARAOKEECHO FADE MUTING FM/AM AUX CD TAPE RMSMXK50U REMOTE CONTROL RadioFans.CN 收音机爱 好者资料库 MX-K50 1-2 1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protec

5、tion, 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 shou

6、ld 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

7、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 t

8、hese 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 c

9、haracteristics 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, movin

10、g 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

11、 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

12、 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

13、 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

14、 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 resi

15、stor. 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

16、 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.

17、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 th

18、is 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 corresp

19、ond to J and C version.) RadioFans.CN 收音机爱 好者资料库 1-3 MX-K50 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 traver

20、se 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. B

21、e 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-

22、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 part

23、s 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 (optica

24、l 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.

25、 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 shee

26、t) 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 wir

27、e 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 mec

28、hanism assembly. Soldering Fig.1 Fig.2 Card wire Card wire Picup unit connector Picup unit connector CD changer unit CD changer mechanism MX-K50 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 exp

29、osure 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 ra

30、diation when the drawer is open 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 spe

31、cified herein may result in hazardous radiation exposure. ! Please use enough caution not to see the beam directly or touch it in case of an adjustment or operation check. Position of labels WARNING LABEL CLASS 1 LASER PRODUCT 1-5 MX-K50 Remove the three screws A attaching the metal cover on the bac

32、k 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 cover (See Fig.1) ONE POINT How to eject the CD tray (see fig.2) Although it will end

33、 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

34、 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 and CD tray fitting. Remove

35、the card wire attached to CD changer unit on the adhesion tape. Disconnect the card wire from the connector CW105 on the CD board. Disconnect the harness from the connector RCW6 on the main board. Remove the two screws C attaching the CD changer unit to the rear panel. Remove the two screws D attach

36、ing the CD changer unit to both sides of the 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 pulle

37、y gear (See fig.1) Fig.4 CD changer unit Card wire Adhesion tape MX-K50 1-6 Prior to performing the following procedure, remove the metal cover and CD changer unit. Disconnect the card wire from the connector FCW3 on the main board. Disconnect the harness from the connector ECW1, JCW1, JCW2 and HCW3

38、 on the main board. Remove the screw E attaching the earth terminal extending from the cassette mechanism assembly. 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 attach

39、ing the front panel assembly to 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 board CD changer unit Main board CW105 Rear panel C D

40、(both sides) Rear panel CD changer unit Front panel assembly Fig.8 Fig.9 Main board Amp. board FCW3 JCW2 JCW1 ECW1 HCW3ACW1 ACW2 Front panel assembly Joint1 (both sides) F (both sides) Joint1 (both sides) F (both sides) E(fixing the earth wire) Front panel assembly G Main board 1-7 MX-K50 Prior to p

41、erforming the following procedure, remove the metal cover and CD changer unit. Disconnect the card wire from 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

42、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 lay controller segment/timing withinternal pull-down resistor in common Internal pull-down resistor output Power p

43、in (+) Output for VFD display controller High voltage input port PC0 to PC3 Power pin (+) for the VFD output pull-down resist Output for VFD display controller High voltage input port PC4 to PC7, PD0 to PD7 Output for VFD displaya controller segment High voltage input port PE0 to PE7 Power pin (+) O

44、utput for VFD displaya controller segment High voltage input port PF0 to PF7 Output for VFD displaya controller segment High voltage I/O port PG0 to PG3 8-bit input/output port. Input for port0 interrupt. Input/output in nibble unit Input for HOLD release 15V withstand at N-channel open drain output

45、 Power pin (-) Power pin (+) 8-bit input/output port. Input for port0 interrupt. Input/output in nibble unit Input for HOLD release 15V withstand at N-channel open drain output SIO0 data output SIO0 data input/bus input/output SIO0 clock input/output SIO1 data output SIO1 data input/bus input/output

46、 SIO1 clock input/output 8-bit input/output port Input/output can be specified in a bit unit 3. Pin function MX-K50 1-36 HA12237 (JIC1) : Audio signal processor 1. Block diagram REC OUT(L) NC ALC(L) TEST (Open for normal use) IREF ALC ON/OFF High/Normal A (REC RETURN ON/OFF) Vcc MUTE ON/OFF REC MUTE

47、 OFF/ON GND ALCDET A/B MUTE 120/60 (Norm/High) REC OUT(R) NC NC TAI(R) EQOUT(R) PB-EQ(R) ALC(R) REC IN(R) 14568910 AB 732 Return SW + EQ ALC PB OUT(R) PB-NF2(R) 34 35 36 37 38 39 40 GND REC Return IN(L) AIN(R) IN(R) PB-NF1(R) Return SW NC 30 31 32 33RIP AB 28 120/60 (Norm/High) AIN(L) PB-NF1(L) 29 +

48、 TAI(L) EQOUT(L) PB-NF2(L) PB-EQ(L) 21222324252627 MUTE EQ NC PB OUT(L) REC IN(L) 11 12 13 14 15 16 17 18 19 20 2. Pin function Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Symbol PB-NF2(R) PB-EQ(R) EQOUT(R) TAI(R) PBOUT(R) NC RECIN(R) NC RECOUT(R) ALC ON/OFF High/Norm A/B MUTE ON/OFF Function PB EQ fee

49、d back NAB output EQ output Tape input PB output NC pin REC-EQ input NC pin REC output Mode control input Mode control input Mode control input Mode control input Pin No. 15 16 17 18 19 20 21 22 23 24 25 26 Symbol REC MUTE OFF/ON Vcc GND IREF Test mode RECOUT(L) NC RECIN(L) NC PBOUT(L) Function Mode control input Vcc pin GND pin Equalizer reference current input Test mode pin REC output NC pin REC-EQ input NC pin PB output Pin No. 27 28 29 30 31 32 33 34 35 36