Sony MDS-JE640 specifications Focus Bias Adjustment, Yes

Page 28

11.Rotate the AMS knob until 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

12.Press the YES button, and save the adjustment results in the non-volatile memory. (“EFB = SAVE” will be displayed for a moment.)

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

13.Press the A button and remove the disc.

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

15.Roteto AMS knob and display “EF CD ADJUS”.

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

17.Rotate 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

 

button, display “EFB = SAVE” for a mo-

YES

 

ment and save the adjustment results in the non-volatile memory.

 

Next “EF CD ADJUST” will be displayed.

19.

Press the A button and remove the check disc (MD) TDYS-1.

Note 1 : MO reading data will be erased during if a recorded disc is used in this adjustment.

Note 2 : If the traverse waveform is not clear, connect the oscillo- scope as shown in the following figure so that it can be seen more clearly.

Oscilloscope

BD board

330 k

CN105 pin 4 (TE)

10pF

CN105 pin 6

(VC)

 

5-13. FOCUS BIAS ADJUSTMENT

Adjusting Procedure :

1.Load a test disk (MDW-74/GA-1).

2.Rotate the AMS knob and display “CPLAY1 MODE”.

3.Press the YES button and display “CPLAY1 MID”.

4. Press the

MENU/NO

button when “C1 =

AD = ” is

displayed.

 

5.Rotate the AMS knob and display “FBIAS ADJUST”.

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.Rotate the AMS knob in the clockwise direction and find the focus bias value at which the C1 error rate becomes 220 (Refer to Note 2).

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

9.Rotate the AMS knob in the counterclockwise direction and find the focus bias value at which the C1 error rate becomes 220.

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

11.Check that the C1 error rate is below 20 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 adjustment from step 2.

13.Press the A button to remove the test 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 automatically calculated from points a and b.

Note 2 : As the C1 error rate changes, perform the adjustment us- ing the average vale.

C1 error

220

b

c

a

Focus bias value

 

 

 

(F. BIAS)

28

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Contents Specifications InputsOutputs NEWSupplied accessories SELF-DIAGNOSIS FunctionGeneral Three- or five Digit code Cause/Remedy MessageItems of Error History Mode Items and Contents Table of Contents DisassemblyDiagrams Exploded ViewsSection Service Notes Flexible Circuit Board RepairingJIG for Checking BD Board Waveform IOPRecord Precedure Forced Reset Checks Prior to Parts Replacement and AdjustmentsMain Board Component Side Retry Cause Display Mode Bit BinaryHexadecimal t Binary Conversion Table Section General Section Disassembly Front Panel SectionMain Board PT BOARD, VOL-SEL BoardMechanism Deck Section MDM-7A BD BoardSection Test Mode Precautions for USE of Test ModeSetting the Test Mode Exiting the Test ModeSelecting the Test Mode Display Details Mark GroupOperating the Continuous Playback Mode MENU/NOTest Mode Displays Mode displayError rate display Functions of Other ButtonsWhen Memory NG is Displayed Meanings of Other DisplaysAutomatic SELF-DIAGNOSIS Function InformationParts Replacement and Adjustment Section Electrical AdjustmentsCheck before replacement Adjustment flow YESPrecautions for USE of Optical PICK- UP KMS-260B Precautions for Checking Laser Diode EmissionPrecautions for Adjustments Using the Continuously Recorded Disc Checks Prior to RepairsAuto Check Other ChecksPlay Check MO Error Rate Check CD Error Rate CheckTemperature Compensation Offset Adjutment Initial Setting of Adjustment ValueLaser Power Adjustment Traverse Adjustment Iop NV SaveFocus Bias Adjustment YESError Rate Check Auto Gain Control Output Level AdjustmentCD Auto Gain Control Output Level Adjustment MO Auto Gain Control Output Level AdjustmentAdjusting Points and Connecting Points Section Diagrams For schematic diagramsFor printed wiring boards Circuit Boards LocationSignal Path Block Diagrams BD SectionMDS-JE640 Main Section REC AnalogMain Board BD BoardDisplay Board Printed Wiring Board BD Section SemiconductorPIN PIN Function Printed Wiring Board Main Section Side a IC1 Printed Wiring Board Main Section Side BIC2 PIN MDS-JE640 Schematic Diagram Main /3 See page 47 for IC Block Diagrams Printed Wiring Board Power Section Printed Wiring Board Display Section Schematic Diagram Display Section See page 34 for Waveforms IC Block Diagrams IC101 CXA2523AR BD BoardIC400 LA5643 Main Board IC PIN Functions IC101 CXA2523AR RF Amplifier BD BoardMNT0 FOK Mvci Tfdr IC1 M30805SGP System Control Main Board HLDA/ALE Section Exploded Views Chassis SectionPanel ASSY, Front Black AEP,UK,CIS,SP,MY Panel ASSY, Front SilverMechanism MDM-7A 202 220 201 213 215 216 205 218 207HEAD, Over Light Motor ASSY, SpindleMotor ASSY, Sled Motor ASSY, LoadingSection Electrical Parts List IC TC7WU04FUTE12R Metal ChipIC MC74ACT08DTR2 IC BA033FP-E2Display KEY-SW Main PIN, Connector 3P CONNECTOR, FFC 17PPIN, Connector 4P PLUG, Connector 10P DiodeIC SN74LVU04ANSR AEP,UK,CISTransistor UN2211-TX Transistor UN2111-TXConnector TRANSFORMER, Power CNDTRANSFORMER, Power SP,MY Composition Circuit BlockVOL-SEL Sony Corporation