Sony MDS-JB920 service manual Section Electrical Adjustments, Parts Replacement and Adjustment

Page 23

SECTION 5

ELECTRICAL ADJUSTMENTS

1.PARTS REPLACEMENT AND ADJUSTMENT

• Check and adjust the MDM and MBU as follows. The procedure changes according to the part replaced

•Temperature compensation offset check

•Laser power check

•Traverse check

•Focus bias check

•C PLAY check

•Self-recording/playback check

OK

NG

Parts Replacement and Repair

Has the OWH been replaced?

YES

NO

Has OP, IC171, IC101, or

IC121 been replaced?

YES

Initial setting of the adjustment value

NO

Has OP or IC171 been replaced?		NO

YES

IOP information recording (IOP value labeled on OP)

Has IC171 or D101 been replaced?

YES

NO

Temperature compensation offset adjustment

•Laser power adjustment

•Traverse adjustment

•Focus bias adjustment

•Error rate adjustment

•Focus bias check

•Auto gain adjustment

• Abbreviation

OP : Optical pick-up

OWH : Overwrite head

Check the sled and spindle mechanisms.

Other causes can be suspected.

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Contents MDM-5A SpecificationsMDS-JE520 General SELF-DIAGNOSIS FunctionItems of Error History Mode Items and Contents Section Servicing Notes Table of ContentsDiagrams Varoitus Flexible Circuit Board RepairingVarning IOP JIG for Checking BD Board WaveformRecord Precedure REC/PLAY Checks Prior to Parts Replacement and AdjustmentsForced Reset Precedure Retry Cause Display ModeHexadecimal nBinary Conversion Table Front view Rear view Section GeneralLocation of Controls Page Page Case Section DisassemblyMain Board Front Panel SecitonSlider CAM Mechanism Section MDM-5ASW BOARD, Loading Motor M103 Base Unit MBU-5A, BD BoardExiting the Test Mode Section Test ModePrecautions for USE of Test Mode Setting the Test ModeDisplay Contents Mark Group Selecting the Test ModeMID Operating the Continuous Playback ModeNon-Volatile Memory Mode EEP Mode Detrack check display Not used in servicing Test Mode DisplaysFunctions of Other Buttons Auto gain display Not used in servicingMeanings of Other Displays Display Contents When Lit When OffParts Replacement and Adjustment Section Electrical AdjustmentsLaser power meter Precautions for Checking Laser Diode EmissinonPrecautions for USE of Optical PICK-UP KMS-260A Precautions for AdjustmentsTraverse Check Temperature Compensation Offset CheckLaser Power Check Check Prior to RepairsSelf-Recording/playback Check Play Checking MO Error Rate CheckCD Error Rate Check Focus Bias CheckRecording and Displaying the IOP Information Initial Setting of Adjustment ValueTemperature Compensation Offset Adjutment Laser Power AdjustmentTraverse Adjustment Focus Bias Adjustment MO Auto Gain Control Output Level Adjustment Error Rate CheckAuto Gain Control Output Level Adjustment CD Auto Gain Control Output Level AdjustmentAdjusting Points and Connecting Points IC PIN Function Description Section DiagramsBD Board IC101 CXA2523AR RF AMP, FOCUS/TRACKING Error AMP Sqsy SrdtSens XrstAsyo XrasXWE MvciSpfd SrdrSfdr SprdMain Board IC100 CXD8607N A/D Converter Lvdd AvddlVDD1 TEST2Main Board IC800 M30610MCA-264FP System Controller MDS-JB920 REC Digital Block Diagram Servo Section∙ Signal Path REC AnalogPlay Digital OUT Block Diagram Main Section∙ Signal Path Play Analog OUT Circuit Boards Location Printed Wiring Boards BD Section MDS-JB920 53 for Waveforms. See page 70 and 71 for IC Block Diagrams Schematic Diagram BD /2 SeeWaveforms BD board Main board Disp board MDS-JB920 MDS-JB920 MDS-JB920 MDS-JB920 Other layers pattern Side a US, CND Schematic Diagram Panel Section See page 54 for Waveforms CXA2523AR Schematic Diagram BD Switch SectionPrinted Wiring Board BD Switch Section IC Block Diagrams BD Board IC101IC152 BH6511FS-E2 IC121 CXD2654RCXA8042AS Main Board IC100 CXD8607NIC101 CXA8054M IC203IC200 CXD8767N SN74HCU04ANS-E20 SN74HC153ANSChassis Section Section Exploded ViewsSupplied with RV760 Front Panel Section209 4-988-466-21 Spring ELECTROSTATIC, Leaf 206 201204 205 Base Unit Section MBU-5A Section Electrical Parts List CXA2523AR TANTAL. ChipDiode Diode F1J6TPDisp Main C252 Mylar SN74HC153ANS HZS6C1LHZ7.5CP-TK CXA8042AS390 LED SEL6810A-TH10 Mega Control Transistor Main PSWCoil with Core Vibrator LED SEL6210S-TH10 StandbySW VOL Sony Corporation