Sony NEW, MDM-7A Precautions for Checking Laser Diode Emission, Precautions for Adjustments

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5-2. PRECAUTIONS FOR CHECKING LASER DIODE EMISSION

To check the emission of the laser diode during adjustments, never view directly from the top as this may lose your eye-sight.

5-3. PRECAUTIONS FOR USE OF OPTICAL PICK- UP (KMS-260B)

As the laser diode in the optical pick-up is easily damaged by static electricity, solder the laser tap of the flexible board when using it. Before disconnecting the connector, desolder first. Before connect- ing the connector, be careful not to remove the solder. Also take adequate measures to prevent damage by static electricity. Handle the flexible board with care as it breaks easily.

pick-up	flexible board

laser tap

Optical pick-up flexible board

5-4. PRECAUTIONS FOR ADJUSTMENTS

1)When replacing the following parts, perform the adjustments and checks with in the order shown in the following table.

2)Set the test mode when performing adjustments. After completing the adjustments, exit the test mode.

Perform the adjustments and checks in “group S” of the test mode.

3)Perform the adjustments to be needed in the order shown.

4)Use the following tools and measuring devices.

•Check Disc (MD) TDYS-1 (Parts No. 4-963-646-01)

•Test Disk (MDW-74/GA-1) (Parts No. 4-229-747-01)

•Laser power meter LPM-8001 (Parts No. J-2501-046-A)

or

MD Laser power meter 8010S (Parts No. J-2501-145-A)

•Oscilloscope (Measure after performing CAL of prove.)

•Digital voltmeter

•Thermometer

•Jig for checking BD board waveform (Parts No. : J-2501-196-A)

5)When observing several signals on the oscilloscope, etc., make sure that VC and ground do not connect inside the oscillo- scope.

(VC and ground will become short-circuited.)

6)Using the above jig enables the waveform to be checked without the need to solder.

(Refer to Servicing Note on page 6.)

7)As the disc used will affect the adjustment results, make sure that no dusts nor fingerprints are attached to it.

				Parts to be replaced
Adjustment
Adjustment	Optical	IC101	IC102	IC151	IC190	IC195	D101
	Pick-up	IC101	IC102	IC151	IC190	IC195	D101
	Pick-up

5-7. Initial setting of adjustment values

5-8. Recording of Iop information

5-9. TEMP ADJUST

5-10. Laser power adjustment

5-11. Iop NV Save

5-12. Traverse adjustment

5-13. Focus bias adjustment

5-16. Auto gain adjustment

5-6-4. AUTO CHECK

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Contents Inputs SpecificationsOutputs SELF-DIAGNOSIS Function Where purchased Power requirementsSupplied accessories GeneralItems of Error History Mode Items and Contents Diagrams Table of ContentsDisassembly Exploded ViewsFlexible Circuit Board Repairing Section Service NotesSafety CHECK-OUT LeakageJIG for Checking BD Board Waveform IOPRecord Precedure Forced Reset Checks Prior to Parts Replacement and AdjustmentsMain Board Component Side Retry Cause Display Mode Bit BinaryHigher Bits Lower Bits Hexa Details Bit When BinaryHexadecimal Binary Section General Section Disassembly Front Panel SectionMain Board PT BOARD, VOL-SEL BoardMechanism Deck Section MDM-7A BD BoardSetting the Test Mode Section Test ModePrecautions for USE of Test Mode Exiting the Test ModeSelecting the Test Mode Display Details Mark GroupOUT Operating the Continuous Playback ModeMID MENU/NOError rate display Test Mode DisplaysMode display Functions of Other Buttons Automatic SELF-DIAGNOSIS Function When Memory NG is Displayed Meanings of Other Displays 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 RepairsTraverse Check Auto CheckOther Checks Traverse WaveformFocus Bias Check Play Check MO Error Rate CheckCD Error Rate Check Self-Recording/playback CheckTemperature Compensation Offset Adjutment Initial Setting of Adjustment ValueLaser Power Adjustment Traverse Adjustment Iop NV SaveFocus Bias Adjustment YESCD Auto Gain Control Output Level Adjustment Error Rate CheckAuto Gain Control Output Level Adjustment MO Auto Gain Control Output Level AdjustmentAdjusting Points and Connecting Points For printed wiring boards Section DiagramsFor schematic diagrams Circuit Boards LocationBlock Diagrams BD Section MDS-JE440Main Section Sclk Cclk Control Generator OSCMain Board BD 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 FunctionMNT2 Xbusy MNT0 FOKMNT1 Shck MNT3 SlocAsyi MvciAsyo AvddFrdr TfdrFfdr 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