Sony MDM-7A, NEW, KMS-2608/J1N Auto Check, Other Checks, Traverse Check, Traverse Waveform

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5-6-4. Auto Check

This test mode performs C-REC and C-PLAY automatically for mainly checking the characteristics of the optical pick-up. To perform this test mode, the laser power must first be checked. Perform Auto Check after the laser power check and Iop compare.

Procedure

1.Press the YES button. If “LDPWR minicheck” is displayed, it means that the laser power check has not been performed. In this case, perform the laser power check and Iop compare, and then repeat from step 1.

2.If a disc is in the mechanical deck, it will be ejected forcibly. “DISC IN” will be displayed in this case. Load a test disc (MDW- 74/GA-1) which can be recorded.

3.If a disk is loaded at step 2, the check will start automatically.

4.When “XX CHECK” is displayed, the item corresponding to

XX will be performed.

When “06 CHECK” completes, the disc loaded at step 2 will be ejected. “DISC IN” will be displayed. Load the check disc (MD) TDYS-1.

5.When the disc is loaded, the check will automatically be resumed from “07 CHECK”.

6.After completing to test item 12, check OK or NG will be displayed. If all items are OK, “CHECK ALL OK” will be displayed. If any item is NG, it will be displayed as “NG:xxxx”.

When “CHECK ALL OK” is displayed, it means that the optical pick-up is normal. Check the operations of the other spindle motor, thread motor, etc.

When displayed as “NG:xxxx”, it means that the optical pick-up is faulty. In this case, replace the optical pick-up.

5-6-5. Other Checks

All the following checks are performed by the Auto Check mode. They therefore need not be performed in normal operation.

1.Load a continuously recorded test disc (MDW-74/GA-1). (Refer to “5-5. Using the Continuously Recorded Disc”.)

5-6-6. Traverse Check

Connection :

Oscilloscope

BD board

CN105 pin 4 (TE)

CN105 pin 6 (VC)

V : 0.5 V/div

H : 10 ms/div

Input : DC mode

Checking Procedure:

1.Connect an oscilloscope to CN105 pin 4 (TE) and CN105 pin 6 (VC) of the BD board.

2.Load a test disc (MDW-74/GA-1). (Refer to Note 1.)

3.Press the M button and move the optical pick-up outside the pit.

4.Rotate the AMS knob and display “EF MO CHECK”.

5.Press the YES button and display “EFB = MO-R”.

(Laser power READ power/Focus servo ON/tracking servo OFF/ spindle (S) servo ON)

6.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob. (Read power traverse checking)

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

Offset value (%) = IA – BI X 100 2 (A + B)

7.Press the YES button and display “EFB = MO-W”.

8.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob. (Write power traverse checking)

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

Offset value (%) = IA – BI X 100 2 (A + B)

9. Press the YES button display “EFB = MO-P”.

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

10.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob.

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

Offset value (%) = IA – BI X 100 2 (A + B)

11.Press the YES button display “EF MO CHECK” The disc stops rotating automatically.

12.Press the A button and remove the disc.

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

14.Roteto the AMS knob and display “EF CD CHECK” (C04).

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

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Contents Specifications InputsOutputs Where purchased Power requirements Supplied accessoriesSELF-DIAGNOSIS Function GeneralItems of Error History Mode Items and Contents Table of Contents DisassemblyDiagrams Exploded ViewsSection Service Notes Safety CHECK-OUTFlexible Circuit Board Repairing LeakageJIG for Checking BD Board Waveform IOPRecord Precedure Checks Prior to Parts Replacement and Adjustments Forced ResetMain Board Component Side Retry Cause Display Mode Bit BinaryBit When Binary Higher Bits Lower Bits Hexa DetailsHexadecimal Binary 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 MIDOUT MENU/NOTest Mode Displays Mode displayError rate display Functions of Other ButtonsWhen Memory NG is Displayed Meanings of Other DisplaysAutomatic SELF-DIAGNOSIS Function InformationSection Electrical Adjustments Parts Replacement and AdjustmentCheck before replacement Adjustment flow YESPrecautions for Checking Laser Diode Emission Precautions for USE of Optical PICK- UP KMS-260BPrecautions for Adjustments Using the Continuously Recorded Disc Checks Prior to RepairsAuto Check Other ChecksTraverse Check Traverse WaveformPlay Check MO Error Rate Check CD Error Rate CheckFocus Bias Check Self-Recording/playback CheckInitial Setting of Adjustment Value Temperature Compensation Offset AdjutmentLaser 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 LocationBlock Diagrams BD Section MDS-JE440Main Section Sclk Cclk Control Generator OSCBD Board Main BoardDisplay Board Printed Wiring Board BD Section SemiconductorPIN PIN Function Printed Wiring Board Main Section Side a Printed Wiring Board Main Section Side B PIN MDS-JE440 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 Pin No Pin Name FunctionMNT0 FOK MNT1 ShckMNT2 Xbusy MNT3 SlocMvci AsyoAsyi AvddTfdr FfdrFrdr FS4IC1 M30805SGP System Control Main Board HLDA/ALE Section Exploded Views Chassis SectionNot supplied FL771 Mechanism MDM-7A 202 220 201 213 215 216 205 218 207259 Section Electrical Parts List Description Remarks Ref. NoIC TC7WU04FUTE12R SWITCH, Keyboard MENU/NO Display KEY-SWMain CN1Diode MA8047-TX Main VOL-SEL VibratorSony Corporation