Sony 4-216-840-0 service manual Focus Bias Adjustment, ING CONTINUOUSLY-RECORDED Disc

Page 27

8.Turn the = AMS + knob so that the waveform of the oscilloscope becomes the specified value.

(When the = AMS + knob is turned, the of “EFB-

” changes and the waveform changes.) In this adjustment, waveform varies at intervals of approx. 2%. Adjust the wave- form so that the specified value is satisfied as much as pos- sible.

(Write power traverse adjustment)

(Traverse Waveform)

A

VC

B

Specification A = B

9.Press the [YES] button, and save the adjustment results in the

non-volatile memory. (“EFB = SAV” will be displayed for a moment.)

10.“EFB = MO-P”. will be displayed.

The optical pick-up moves to the pit area automatically and servo is imposed.

11.Turn the = AMS + knob until the waveform of the os- cilloscope moves closer to the specified value.

In this adjustment, waveform varies at intervals of approx. 2%. Adjust the waveform so that the specified value is satisfied as much as possible.

(Traverse Waveform)

A

VC

B

Specification A = B

12.Press the [YES] button, and save the adjustment results in the

non-volatile memory. (“EFB = SAV” will be displayed for a moment.)

Next “EF MO ADJUST” is displayed. The disc stops rotating automatically.

13.Press the [ÊÊÊÊÊEJECT]¤ button and take out the disc.

14.Load the check disc (MD) TDYS-1.

15.Turn the =AMS + knob and display “EF CD ADJUST” (C12).

16.Press the [YES] button and display “EFB = CD”. Servo is imposed automatically.

17.Turn the = AMS + knob so that the waveform of the oscilloscope moves closer to the specified value.

In this adjustment, waveform varies at intervals of approx. 2%. Adjust the waveform so that the specified value is satisfied as much as possible.

(Traverse Waveform)

A

VC

B

Specification A = B

18.Press the [YES] button, display “EFB = SAV” for a mo- ment and save the adjustment results in the non-volatile memory.

Next “EF CD ADJUST” will be displayed.

19.Press the [ÊÊÊÊÊEJECT]¤ button and take out the disc.

12.FOCUS BIAS ADJUSTMENT

Adjusting Procedure :

1.Load the continuously-recorded disc. (Refer to “5. CREAT-

ING CONTINUOUSLY-RECORDED DISC”)

2.Turn the =AMS + knob and display “CPLAY MODE” (C29).

3.Press the [YES] button and display “CPLAY MID”.

4.Press the [MENU/NO] button when “C1 = AD = ” is displayed.

5.Turn the =AMS + knob and display “FBIAS ADJUST” (C13).

6.Press the [YES] button and display “ / a = ”.

The first four digits indicate the C1 error rate, the two digits after [/] indicate ADER, and the 2 digits after [a =] indicate the focus bias value.

7.Turn the =AMS + knob in the clockwise direction and find the focus bias value at which the C1 error rate becomes about 200 (Refer to Note 2).

8.Press the [YES] button and display “ / b = ”.

9.Turn the = AMS + knob in the counterclockwise di- rection and find the focus bias value at which the C1 error rate becomes about 200.

10.Press the [YES] button and display “ / c = ”.

11.Check that the C1 error rate is below 50 and ADER is 00. Then press the [YES] button.

12.If the “( )” in “ - - ()” is above 20, press the [YES] button.

If below 20, press the [MENU/NO] button and repeat the ad- justment from step 2.

13.Press the [ÊÊÊÊÊEJECT]¤ button and take out the disc.

Note 1: The relation between the C1 error and focus bias is as shown in the following figure. Find points A and B in the following figure using the above adjustment. The focal point position C is auto- matically calculated from points A and B.

Note 2: As the C1 error rate changes, perform the adjustment using the average vale.

C1 error

about 200

B

C

A

Focus bias value

 

 

 

(F. BIAS)

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Contents Specifications MDS-JE520MDM-5A SELF-DIAGNOSIS Function Items of Error History Mode Items and Contents Table of Contents DiagramsSection Servicing Notes Varning Flexible Circuit Board RepairingIOP JIG for Checking BD Board WaveformRecord Precedure Criteria for Determination Measure if unsatisfactory Checks Prior to Parts Replacement and AdjustmentsPrecedure Retry Cause Display ModeHexadecimal nBinary Conversion Table Section General Section Disassembly CoverFront Panel Section Mechanism Deck Section MDM-5A Main BoardBase Unit MBU-5A, BD Board Slider CAMSW BOARD, Loading Motor M103 Exiting the Test Mode Section Test ModePrecautions for USE of Test Mode Setting the Test ModeDisplay Contents Mark Group Selecting the Test ModeOUT Operating the Continuous Playback ModeNon-Volatile Memory Mode EEP Mode MIDFunctions of Other Buttons Test Mode DisplaysMeanings of Other Displays Parts Replacement and Adjustment Section Electrical AdjustmentsLaser power meter Precautions for Checking Laser Diode EmissionPrecautions 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 Adjustment Laser Power AdjustmentTraverse Adjustment ING CONTINUOUSLY-RECORDED Disc Focus Bias AdjustmentMO Auto Gain Control Output Level Adjustment Error Rate CheckAuto Gain Control Output Level Adjustment CD Auto Gain Control Output Level AdjustmentAdjustment Location IC PIN Function Description Section DiagramsSens MNT2 XbusyXlat SrdtAsyi XrasXWE AsyoSprd FS4Srdr SfdrRST AderByte CnvssLD-LOW STBChack LdinREC Analog REC Digital Block Diagram MD Servo Section∙ Signal Path Play Analog OUTREC Analog Block Diagram Main SectionCND Circuit Boards LocationSemiconductor Location MDS-M100 65 for Waveforms. See page 51 for IC Block Diagram Schematic Diagram BD Board 2/2 SeePrinted Wiring Board SW Board Schematic Diagram SW BoardIC152 BH6511FS-E2 IC121 CXD2654RMain Board IC301 ΜDA1341TS/N2 IC406 M62016L IC421 M5293LMDS-M100 Semiconductor Location Schematic Diagram Main Board 1/2 See page 65 for Waveform MDS-M100 Ref. No Location D741 D742 IC761 Q741 Q742 Q767 MDS-M100 Section Exploded ViewsCover Section AEP, SP Chassis Section221 A-4680-409-A Holder Complete Assy Mechanism Section MDM-5A201 206 204 205 209 4-988-466-11 Spring ELECTROSTATIC, LeafBase Unit Section MBU-5A AC Select BD Section Electrical Parts ListTransistor FMW1 Short SwitchIC/TRANSISTOR CXA2523ARConnector MainCeramic Inductor CarbonExcept US, CND Main Panel Panel SW Trans Sony Corporation
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