JVC-MXKA7-cs-sm维修电路原理图.pdf

《JVC-MXKA7-cs-sm维修电路原理图.pdf》由会员分享，可在线阅读，更多相关《JVC-MXKA7-cs-sm维修电路原理图.pdf（67页珍藏版）》请在收音机爱好者资料库上搜索。

1、MX-KA7 Contents COPYRIGHT 2003 VICTOR COMPANY OF JAPAN, LTD. No. MB039 2003/11 Safety precautions - 1- 2 Preventing static electricity - 1- 3 Important for laser products - 1- 4 Disassembly method - 1- 5 Adjustment method - 1- 18 Flow of functional operation until TOC read - 1- 20 Maintenance of las

2、er pickup - 1- 21 Replacement of laser pickup - 1- 21 Description of major ICs - 1- 22 CA-MXKA7SP-MXKA7SP-MXKA7 Area Suffix JW . Mexico, Panama SERVICE MANUAL COMPACT COMPONENT SYSTEM MX-KA7 Wiring connection - 1- 33 RadioFans.CN 收音机爱 好者资料库 MX-KA7 1-2 Warning ! CAUTION Good earth ground Place this p

3、robe on each exposed metal part. AC VOLTMETER (Having 1000 ohms/v 1500 10W olts, or more sensitivity) 0.15 F AC TYPE Safety Precautions 1. This design of this product contains special hardware and many circuits and components specially for safety purposes. For continued protection, no changes should

4、 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 des

5、ign 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 h

6、ave 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 cha

7、racteristics 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

8、 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

9、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-as

10、sembling 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 tra

11、nsformer 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 leakag

12、e 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 expos

13、ed 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, revers

14、e 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 en

15、sure 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

16、 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. RadioFans.CN 收音机爱 好者资料库 MX-KA7 1-3 Preventing static electricity 1. Grounding to prevent damage by static electricity Electrostatic discharge (ESD), which o

17、ccurs 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 whic

18、h 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 sh

19、eet) 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,

20、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 eas

21、ily destroy the laser diode. 4. Handling the CD changer unit (optical pickup) 1. Do not subject the CD changer 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 spe

22、cific details, refer to the replacement procedure in the text. Remove the anti-static pin when replacing the CD changer 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

23、 possible to adjust the semi-fixed resistor that adjusts the laser power. Do not turn it. Attention when traverse unit is decomposed * Please refer to “Disassembly method” in the text for pick up and how to detach the CD changer mechanism. 1. Remove the CD changer unit. 2. Disconnect the harness fro

24、m connector on the CD motor board. 3. Solder is put up before the card wire is removed from connector Cn601on the main board as shown in Fig.1 and Fig. 2. (When the wire is removed without putting up solder, the CD pick-up assembly might destroy.) 4. Please remove solder after connecting the card wi

25、re with CN601 when you install picking up in the substrate. Conductive material (conductive sheet) or iron plate (caption) Anti-static wrist strap Soldering Fig.2 Flexible cable Fig.1 CD changer unit MX-KA7 1-4 1. CLASS 1 LASER PRODUCT 2. DANGER : Invisible laser radiation when open and inter lock f

26、ailed 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

27、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 products FUSE CAUTION CAUTION: REPLACE WITH SAME TYPE AND RATING FUSE (S). ATTENTION: REMPLACER PAR UN(LES) F

28、USIBLE(S) DE MEME TYPE ET DE MEME VALEUR 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. ! CAUTION Please use enough cautio

29、n not to see the beam directly or touch it in case of an adjustment or operation check. MX-KA7 1-5 Disassembly method Commence disassembly of the set by removing the main units and then proceed to the components and assemblies inside the units. Replacement of the fuses and the power IC ? Top cover ?

30、 CD changer unit ? Front panel assembly ? Chassis unit ? CD changer unit ? Removing the main PCB ? Removing the CD changer mechanism assembly ? Removing the CD pickup ? Replacing the loading motor and belt of the CD changer tray ? Replacing the CD tray rotor belt of CD changer, and removing the moto

31、r ? Front panel assembly ? Removing the cassette deck mechanism ? Removing the earphone jack PCB ? Removing the control/FL PCB ? Removing the switch PCB and ACTIVE BASS EX. switch PCB ? Removing the cassette deck main motor, and replacing the main belts ? Removing the leaf switches of the cassette d

32、eck mechanism ? Removing the cassette deck heads ? Chassis unit ? Removing the 3-pin regulator ? Removing the power amp and supply PCB and the Power Trans PCB ? Removing the sub power PCB MX-KA7 1-6 Replacement of the fuses and the power IC ? Replacing the fuses (See Fig.1) ? Prior to performing the

33、 following procedure, remove the top cover. 1. Replace the fuses inside. Caution Be sure to use fuses with the specified ratings. ? Replacing the heat sink cover (See Fig.3) 1. Remove four screws B from the rear panel. 2. Pull the heat sink cover outward. Fig.1 Fuse (F951) 3.15A 250V Fuse (F952) 1.6

34、A 250V ? Replacing the power IC (See Fig.2) ? Prior to performing the following procedure, remove the top cover. 1. Remove the two screws A from the heat sink between the power IC. 2. Remove the solder fixing the power IC. A Fig.2 Fig.3 B MX-KA7 1-7 ? Removing the top cover (See Fig.4 and 5) 1. Remo

35、ve six screws C that retain the top cover from the panel rear of the body. 2. Remove six screws D that retain the top cover from the two sides of the body. 3. Remove the top cover from the body by lifting it toward the rear. Fig.5 Fig.4 Right Front panel assembly D D Left Front panel assembly D D To

36、p cover C C MX-KA7 1-8 Fig.6 CD tray panel Fig.9 CD changer unit G Fig.7 CD tray panel Fig.8 ? Removing the CD changer unit (See Fig.6 to 9) ? Prior to performing the following procedures, remove the top cover. Caution Although the CD mechanism unit can be removed without removing the CD tray panel,

37、 it is still recommended to remove it in order to prevent damage. a. From the front panel side of this set, push in the sections marked with arrows and pull out the CD tray toward the front. b. Remove the CD tray panel by pushing both of its extremities upward in the direction of the arrows. c. Push

38、 the CD tray deep into the set. 1. Disconnect the cord wires from the CD PCB CN703 and CN203. 2. From the rear of the set, remove two screws E three screws F and four screws G on the front panel left and right side. 3. Handle the CD changer unit rear, take out the unit. F Antenna termianl E Aux term

39、inal MX-KA7 1-9 ? Removing the front panel assembly (See Fig.10 to 11) ? Prior to performing the following procedures, remove the top cover. ? Also remove the CD changer unit. 1. Disconnect the parallel wire and the cord wire from the connectors CN701, CN101 on the power amp. PCB. 2. Remove one scre

40、ws H retaining the front panel assembly onto the bottom of the body. 3. Remove two screws I on the left and right side of the set retaining the panel front from the bottom and then remove then GND lug b that comes from the power amp and supply PCB. 4. Disengage the claws c on both sides of the front

41、 panel assembly and then remove the assembly. Fig.10 H Fig.11 I er amp andPow supply PCB Claw cGND lug b MX-KA7 1-10 Fig.13 CD PCB Short round CN601 Fig.12 J CD PCB ? Removing the CD PCB (See Fig.12 to 13) ? Prior to performing the following procedures, remove the top cover. ? Also remove the CD cha

42、nger unit. 1. Disconnect the wires from CN603A, CN603B and CN604 on the CD PCB, which is located on the back side of the CD changer unit. 2. The four screws J that retain the CD PCB should be removed. 3. Remove the CD PCB by pulling it toward the side where the CN601 is located. 4. Using solder, sho

43、rt the CD pickup to connect to short round. Caution After re-connecting the wires, be sure to remove the shorting solder from the GND connection. 5. Disconnect the card wire from the connector CN601 on the main PCB and then remove the main PCB. JJ MX-KA7 1-11 Fig.14 Fig.15 assembly e ( Silver color)

44、 e ( copper color) e ( Silver color)e ( copper color) d CD changer unit ? Removing the CD changer mechanism assembly (See Fig.14 to 15) ? Prior to performing the following procedures, remove the top cover. ? Also remove the CD changer unit. 1. Turn the CD changer mechanism cover base and remove the

45、screws d connecting the unit to the CD changer mechanism assembly. 2. Removing four screws e retaining the CD mechanism holder assembly. Caution When replacing the CD changer mechanism assembly, be sure not to mistake the positions of the silver color and copper color spring. CD changer mechanism MX

46、-KA7 1-12 Fig.16 Fig.17 Fig.18 Motor locker Turn table motor Obligue gear , and then remove the CD tray g M L f CD pickup Shaft ? Removing the CD pickup (See Fig.16) ? Prior to performing the following procedures, remove the top cover. ? Also remove the CD changer unit. ? Also remove the CD changer

47、mechanism. 1. Widen the section f. 2. While keeping the section f wide open, push the section g in the direction of the arrow to remove the shaft, and then remove the CD pickup. ? Replacing the loading motor and rotor belt of the CD changer (See Fig .17) ? Prior to performing the following procedure

48、s, remove the top cover. ? Also open the CD changer tray. 1. Remove the two screws L retaining the CD changer tray loading motor. 2. Remove the two screws M retaining the gear plate and take it out, after remove the rotor belt from the pulley. ? Replacing the CD turn table and remov- ing the motor (See Fig. 19 ) ? Prior to performing the following procedures, remove the top cover. ? Also remove the CD changer unit. 1. Remove the one screws N retaining the CD (Turn table). 2. Remove the two screws O retaining the stopper brackets on both sides of the CD changer unit. 3. Remo