Jvc-HRXVC-28-BU-Service-Manual 电路图 维修手册.pdf

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1、SERVICE MANUAL COPYRIGHT 2005 Victor Company of Japan, Limited No.YD052 2005/3 DVD PLAYER preset to Channel 3 when shipped) 75 , unbalanced TIMER Clock referenceQuartz Program capacity1- year programmable timer/8 programs ACCESSORIES Provided accessoriesRF cable, Infrared remote control unit, AA bat

2、tery I I 2 RadioFans.CN 收音机爱 好者资料库 (No.YD052)1- 3 SECTION 1 PRECAUTION 1.1SAFTY PRECAUTIONS Prior to shipment from the factory, JVC products are strictly in- spected to conform with the recognized product safety and elec- trical codes of the countries in which they are to be sold.However,in order to

3、 maintain such compliance, it is equally important to implement the following precautions when a set is being serviced. 1.1.1Precautions during Servicing (1) Locations requiring special caution are denoted by labels and inscriptions on the cabinet, chassis and certain parts of the product.When perfo

4、rming service, be sure to read and comply with these and other cautionary notices appearing in the operation and service manuals. (2) Parts identified by the symbol and shaded ( ) parts are critical for safety. Replace only with specified part numbers. NOTE : Parts in this category also include thos

5、e specified to comply with X-ray emission standards for products using cathode ray tubes and those specified for compliance with various regulations regarding spu- rious radiation emission. (3) Fuse replacement caution notice. Caution for continued protection against fire hazard. Replace only with s

6、ame type and rated fuse(s) as speci- fied. (4) Use specified internal wiring. Note especially: Wires covered with PVC tubing Double insulated wires High voltage leads (5) Use specified insulating materials for hazardous live parts. Note especially: Insulation Tape PVC tubing Spacers Insulation sheet

7、s for transistors Barrier (6) When replacing AC primary side components (transformers, power cords, noise blocking capacitors, etc.) wrap ends of wires securely about the terminals before soldering. Fig.1- 1- 1 (7) Observe that wires do not contact heat producing parts (heatsinks, oxide metal film r

8、esistors, fusible resistors, etc.) (8) Check that replaced wires do not contact sharp edged or pointed parts. (9) When a power cord has been replaced, check that 10- 15 kg of force in any direction will not loosen it. Fig.1- 1- 2 (10) Also check areas surrounding repaired locations. (11) Products us

9、ing cathode ray tubes (CRTs)In regard to such products, the cathode ray tubes themselves, the high volt- age circuits, and related circuits are specified for compli- ance with recognized codes pertaining to X- ray emission. Consequently, when servicing these products, replace the cathode ray tubes a

10、nd other parts with only the specified parts. Under no circumstances attempt to modify these cir- cuits.Unauthorized modification can increase the high volt- age value and cause X- ray emission from the cathode ray tube. (12) Crimp type wire connectorIn such cases as when replacing the power transfo

11、rmer in sets where the connections be- tween the power cord and power trans former primary lead wires are performed using crimp type connectors, if replac- ing the connectors is unavoidable, in order to prevent safe- ty hazards, perform carefully and precisely according to the following steps. Conne

12、ctor part number :E03830- 001 Required tool : Connector crimping tool of the proper type which will not damage insulated parts. Replacement procedure a) Remove the old connector by cutting the wires at a point close to the connector.Important : Do not re- use a connector (discard it). Fig.1- 1- 3 b)

13、 Strip about 15 mm of the insulation from the ends of the wires. If the wires are stranded, twist the strands to avoid frayed conductors. Fig.1- 1- 4 c) Align the lengths of the wires to be connected. In- sert the wires fully into the connector. Fig.1- 1- 5 d) As shown in Fig.1- 1- 6, use the crimpi

14、ng tool to crimp the metal sleeve at the center position. Be sure to crimp fully to the complete closure of the tool. Fig.1- 1- 6 e) Check the four points noted in Fig.1- 1- 7. Fig.1- 1- 7 - - - - - - - - - - - - - - RadioFans.CN 收音机爱 好者资料库 1- 4 (No.YD052) 1.1.2Safety Check after Servicing Examine t

15、he area surrounding the repaired location for damage or deterioration. Observe that screws, parts and wires have been returned to original positions, Afterwards, perform the following tests and confirm the specified values in order to verify compli- ance with safety standards. (1) Insulation resista

16、nce test Confirm the specified insulation resistance or greater be- tween power cord plug prongs and externally exposed parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, ear- phone jacks, etc.).See table 1 below. (2) Dielectric strength

17、test Confirm specified dielectric strength or greater between power cord plug prongs and exposed accessible parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.). See Fig.1- 1- 11 below. (3) Clearance distance When repl

18、acing primary circuit components, confirm spec- ified clearance distance (d), (d) between soldered termi- nals, and between terminals and surrounding metallic parts. See Fig.1- 1- 11 below. Fig.1- 1- 8 (4) Leakage current test Confirm specified or lower leakage current between earth ground/power cor

19、d plug prongs and externally exposed ac- cessible parts (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, ear- phone jacks, etc.). Measuring Method : (Power ON)Insert load Z between earth ground/power cord plug prongs and externally ex- posed accessible

20、parts. Use an AC voltmeter to measure across both terminals of load Z. See Fig.1- 1- 9 and follow- ing Fig.1- 1- 12. Fig.1- 1- 9 (5) Grounding (Class 1 model only) Confirm specified or lower grounding impedance between earth pin in AC inlet and externally exposed accessible parts (Video in, Video ou

21、t, Audio in, Audio out or Fixing screw etc.).Measuring Method: Connect milli ohm meter between earth pin in AC inlet and exposed accessible parts. See Fig.1- 1- 10 and grounding specifications. Fig.1- 1- 10 Fig.1- 1- 11 Fig.1- 1- 12 NOTE : These tables are unofficial and for reference only. Be sure

22、to confirm the precise values for your particular country and locality. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - (No.YD052)1- 5 1.2Preventing static electricity Electrostatic discharge (ESD), which occurs when static electricity stored in the body, fabric,

23、etc. is discharged, can destroy the laser diode in the traverse unit (optical pickup). Take care to prevent this when performing repairs. 1.2.1 Grounding to prevent damage by static electricity Static electricity in the work area can destroy the optical pickup (laser diode) in devices such as DVD pl

24、ayers. Be careful to use proper grounding in the area where repairs are being performed. (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) Ground yourself Use

25、an anti- static wrist strap to release any static electricity built up in your body. (3) Handling the optical pickup 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 short

26、ed parts to their original condition. (Refer to the text.) 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- 6 (No.YD052) 1.3Precautions for Service 1.3.1Handling of Traverse Unit and Laser Pi

27、ckup (1) Do not touch any peripheral element of the pickup or the actuator. (2) The traverse unit and the pickup are precision devices and therefore must not be subjected to strong shock. (3) Do not use a tester to examine the laser diode. (The diode can easily be destroyed by the internal power sup

28、ply of the tester.) (4) To replace the traverse unit, pull out the metal short pin for protection from charging. (5) When replacing the pickup, after mounting a new pickup, remove the solder on the short land which is provided at the center of the flexible wire to open the circuit. (6) Half- fixed r

29、esistors for laser power adjustment are adjusted in pairs at shipment to match the characteristics of the optical block. Do not change the setting of these half- fixed resistors for laser power adjustment. 1.3.2Destruction of Traverse Unit and Laser Pickup by Static Electricity Laser diodes are easi

30、ly destroyed by static electricity charged on clothingor the human body. Before repairing peripheral elements of the traverse unit or pickup, be sure to take the following electrostatic protection: (1) Wear an antistatic wrist wrap. (2) With a conductive sheet or a steel plate on the workbench on wh

31、ich the traverse unit or the pick up is to be repaired, ground the sheet or the plate. (3) It solders to two short circuit sections on the substrate of a pick- up. (4) After removing the flexible wire from the connector (CN101), short- circuit the flexible wire by the metal clip. (5) Short- circuit

32、the laser diode by soldering the land which is provided at the center of the flexible wire for the pickup. After completing the repair, remove the solder to open the circuit. - - - - (No.YD052)1- 7 SECTION 2 SPECIFIC SERVICE INSTRUCTIONS 2.1Different table of feature The following table indicates ma

33、in different points between models HR- XVC28BUC, HR- XVC28BUS, HR- XVC29SUC and HR- XVC29SUS. NOTE : Mark is same as left. 2.2 Service position This unit has been designed so that the Mechanism and Main board assemblies can be removed together from the bottom chassis. Before diagnosing or servicing

34、the circuit boards, take out the major parts from the bottom chassis. 2.2.1How to set the Service position (1) Refer to the disassembly procedure and perform the disas- sembly of the major parts before removing the Mechanism assembly. (2) Remove the screws that fix the Mechanism, Main board as- semb

35、ly to the bottom chassis. If any other screws are used to fix the boards, remove them also. (3) Remove the combined Mechanism and Main board assem- blies. (4) If any other major parts are used, remove them also. (5) Connect the wires and connectors of the major parts that have been removed in steps

36、(1) to (4). (Refer to Fig. 2- 2a.) (6) Place the combined Mechanism, Main board and other board assemblies upside down. (7) Insert the power cord plug into the power outlet and then proceed with the diagnostics and servicing of the board as- sembly. Notes: Before inserting the power cord plug into t

37、he power out- let, make sure that none of the electrical parts are able to short-circuit between the workbench and the board assembly. For the disassembly procedure of the major parts and details of the precautions to be taken, see Removing the major parts. If there are wire connections from the Mai

38、n board and Mechanism assemblies to the other major parts, be sure to remove them (including wires connected to the major parts) first before performing step (2). When carrying out diagnosis and repair of the Main board assembly in the Service position, be sure to ground both the Main board and Mech

39、anism assem- blies. If they are improperly grounded, there may be noise on the playback picture or FDP counter display may move even when the mechanism is kept in an inop- erative status. In order to diagnose the playback or recording of the cassette tape, set the Mechanism assembly to the re- quire

40、d mode before placing it upside down. If the mech- anism mode is changed (including ejection) while it is in an upside down position the tape inside may be dam- aged. For some models, the mechanism and board assem- blies are attached by connectors only. When carrying out a diagnosis or repair of the

41、 boards in the Service position, make sure that the connectors are not dis- connected. Fig.2- 2a 2.3Jig RCU mode This unit uses the following two modes for receiving remote con- trol codes. (1) User RCU mode:Ordinary mode for use by the user. (2) Jig RCU mode: Mode for use in production and servicin

42、g. When using the Jig RCU, it is required to set the VCR to the Jig RCU mode (the mode in which codes from the Jig RCU can be received). As both of the above two modes are stored in the EE- PROM, it is required to set the VCR back to the User RCU mode each time that an adjustment is made or to check

43、 that the neces- sary operations have been completed.These modes can be set by the operations described below. Note: Confirm the RCU mode when exchanged parts. Since some SERVICE PARTS sets the VCR to the Jig RCU mode as initial setting. Therefore please set the VCR to the user RCU mode after replac

44、ing the EEPROM. HR-XVC28BUCHR-XVC28BUSHR-XVC29SUCHR-XVC29SUS BODY COLORBLACKPURE SILVER MP3 PLAYBACKUSEDNOT USEDUSEDNOT USED - - - - - - - 1- 8 (No.YD052) Fig.2- 3a User/Jig RCU mode 2.3.1Setting the Jig RCU mode (1) Turn on the power. (2) Press the following remocon keys continuously within 2 secon

45、ds SET UP 2 8 ENTER . When the VCR is set to the Jig RCU mode, the symbols ( : ) in the time display of the FDP are turned off. (Refer to Fig.2- 3a) 2.3.2Setting the User RCU mode (1) Turn off the power. (2) Press the REC and PAUSE buttons of the VCR simul- taneously. Alternatively, transmit the cod

46、e 43- 80 from the Jig RCU. 2.4Mechanism service mode This model has a unique function to enter the mechanism into ev- ery operation mode without loading of any cassette tape. This function is called the Mechanism service mode. 2.4.1How to set the Mechanism service mode (1) Set the VCR to the Jig RCU

47、 mode (the mode in which codes from the Jig RCU can be received) (2) Transmit the code 43- E5 from the Jig RCU. (3) Release the lug of the Cassette holder and then slide the Cassette holder toward the direction where the Cassette holder is loaded by manually. (4) The cassette holder lowers and, when

48、 the loading has completed, the mechanism enters the desired mode. When the VCR is set to the Mechanism service mode, the symbols (Timer) in the FDP (LED) are blinked. 2.4.2How to exit from the Mechanism service mode (1) Unplug the power cord plug from the power outlet. 2.5Maintenance and inspection 2.5.1C