LG MD MS722H Service Manual

MD-MS722H/MS721H

SERVICE MANUAL

No. SX887MDMS722H

MD-MS722H MD-MS721H(BL)

(Illustration: MD-MS722H)

(Illustration: MD-MS721H)

MD-MS721H(S)

• In the interests of user-safety the set should be restored to its original condition and only parts identical to those specified be used.

• Note for users in UK

Recording and playback of any material may require consent which SHARP is unable to give. Please refer particularly to the provisions of Copyright Act 1956, the Dramatic and Musical Prefomers Protection Act 1956, the Preformers Protection Acts 1963 and 1972 and to any subsequent statutory enactments and orders.

CONTENTS

Page

SAFETY PRECAUTION FOR SERVICE MANUAL ............................................................................................................... 2

SPECIFICATIONS ................................................................................................................................................................. 3

NAMES OF PARTS ............................................................................................................................................................... 4

OPERATION MANUAL .......................................................................................................................................................... 6

DISASSEMBLY...................................................................................................................................................................... 9

INSTALLING THE TOP CABINET ......................................................................................................................................... 9

REMOVING AND REINSTALLING THE MAIN PARTS....................................................................................................... 10

ADJUSTMENT ...................................................................................................................................................................... 11

BLOCK DIAGRAM ............................................................................................................................................................... 27

SCHEMATIC DIAGRAM/WIRING SIDE OF P.W.BOARD................................................................................................... 28

NOTES ON SCHEMATIC DIAGRAM .................................................................................................................................. 35

WAVEFORMS OF CD CIRCUIT.......................................................................................................................................... 36

TROUBLE SHOOTING ........................................................................................................................................................ 37

FUNCTION TABLE OF IC.................................................................................................................................................... 40

PARTS GUIDE/EXPLODED VIEW PACKING METHOD (MD-MS722H FOR UK ONLY)

SHARP CORPORATION

– 1 –

This document has been published to be used for after sales service only. The contents are subject to change without notice.

MD-MS722H/MS721H

SAFETY PRECAUTION FOR SERVICE MANUAL

Precaution to be taken when replacing and servicing the Laser Pickup.

The AEL (Accessible Emission Level) of Laser Power Output for this model is specified to be lower than Class I Requirements. However, the following precautions must be observed during servicing to protect your eyes against exposure to the laser beam.

(1) When the cabinet has been removed, the power is

turned on without a compact disc, and the Pickup is on a position outer than the lead-in position, the Laser will light for several seconds to detect a disc. Do not look into the Pickup Lens.

(2) The Laser Power Output of the Pickup inside the unit

and replacement service parts have already been adjusted prior to shipping.

(3) No adjustment to the Laser Power should be attempted

when replacing or servicing the Pickup.

(4) Under no circumstances look directly into the Pickup

Lens at any time.

(5) CAUTION - Use of controls or adjustments, or

performance of procedures other than those specified herein may result in hazardous radiation exposure.

CAUTION - INVISIBLE LASER RADIATION WHEN OPEN AND INTERLOCKS DEFEATED AVOID EXPOSURE TO BEAM .

VARNING - OSYNLIG LASERSTRÅLNING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRRAR ÄR URKOPPLADE. STRÅLEN ÄR FARLIG.

ADVARSEL - USYNLIG LASERSTRÅLING NÅR DEKSEL ÅPNES OG SIKKERHEDSLÅS BRYTES. UNNGÅ EKSPONERING FOR STRÅLEN.

VARO! AVATTAESSA JA SUOJALUKITUS OHITETTAESSA OLET ALTTIINA NÄKYMÄTÖN LASERSÄTEILYLLE. ÄLÄ KATSO SÄTEESEN.

VARNING - OSYNLIG LASERSTRÅLING NÄR DENNA DEL ÄR ÖPPNAD OCH SPÄRREN ÄR URKOPPLAD. BETRAKTA EJ STRÅLEN.

ADVARSEL - USYNLIG LASERSTRÅLING VED ÅBNING NÅR SIKKERHEDSAFBRYDERE ER UDE AF FUNKTION. UNDGÅ UDSETTELSE FOR STRÅLING.

(MS722H Except for

UK/MS721H)

LASER KLASSE 1 LUOKAN 1 LASERLAITE KLASS 1 LASERAPPARAT

Laser Diode Properties

Material: GaAIAs Wavelength: 785 nm Pulse time:

(MS722H For UK)

Read mode: 0.8 mW Continuous Write mode: max 10 mW 0.5S

min cycle 1.5S Repetition

VAROITUS! LAITTEEN KÄYTTÄMINEN MUULLA KUIN TÄSSÄ KÄYTTÖOHJEESSA MAINITULLA TAVALLA SAATTAA ALTISTAA KÄYTTÄJÄN TURVALLISUUSLUOKAN 1 YLITTÄVÄLLE NÄKYMÄTTÖMÄLLE LASERSÄTEILYLLE.

VARNING - OM APPARATEN ANVÄNDS PÅ ANNAT SÄTT ÄN I DENNA BRUKSANVISNING SPECIFICERAS. KAN ANVÄNDAREN UTSÄTTAS FÖR OSYNLIG LASERSTRÅLNING, SOM ÖVERSKRIDER GRÄNSEN FÖR LASERKLASS 1.

VARO ! Avattaessa ja suojalukitus ohitettaessa olet alttiina näkymättömälle lasersäteilylle. Älä katso säteeseen. VARNING! Osynlig laserstralning när denna del är öppnad och spärren är urkopplad. Betrakta ej strälen.

Precaution to be taken when replacing and servicing the laser pickup. The following precautions must be observed during servicing to protect your eyesagainst exposure to the laser.

Warning of possible eye damage when repairing: If the AC adaptor or batteries are connected when the top houising (disc cover) of the unit is removed, and the PLAY key is pressed, the laser will light up during docus access (2-3 seconds). (Fig. 2-1) During the operation, the laser will lesk from the opening btween the magnetic head and the mechanical chassis (Fig. 2-2). In order to protect your eyes, you most not look at the laser durnd repaor. Before repaoring be sure to disconnect the AC adaptor and remove the batteries.

Magnet head

Mechanism Chassis

Magnet Head

Lasar Beam

Optical pick-up

Main PWB

Disc motor

Figure 2-1 Figure 2-2

Disc cover

– 2 –

Optical Pick-Up

MD-MS722H/MS721H

MD-MS722H

Remote control unit

NAME OF PARTS

1. Synchro Recording Indicator

2. Character/Time Information Indicator

3. Record Indicator

4. Repeat Indicator:

5. Random Indicator

6. Disc Mode Indicator

7. Total Track Number Display

8. Track Number Indicator

9. Battery Indicator:

10. Earphones Socket

11. Display/Volume Shuttle Switch

12. Hold Switch

13. Play/Pause/Fast Reverse/ Fast Forward Shuttle Switch

14. Stop/Power Off/Bass/Play Mode Shuttle Switch

Main unit

1. Monaural Long-Play Mode Indicator

2. Record Indicator

3. Index Indicator

4. Level Meter

5. Repeat Indicator:

6. TOC Indocator

7. Battery Indicator:

8. Random Indicator

9. Track Number Indicator

10. Character/Time Information Indicator

11. Synchro Recording Indicator

12. Disc Mode Indicator

13. Disc Name Indicator

14. Track Name Indicator

15. Remaining Recording Time Indicator

16. Total Track Number Display

17. Jog Dial

18. Record/Track Mark Button

19. Volume/Name Select Buttons: --

20. Display/Lowercase Characters Button

21. Character Button

22. Volume/Name Select Buttons: +

23. Play/Pause Button:

24. Fast Reverse/Fast Forward/Recording Level Control/ Cursor Shuttle Switch:

25. Edit/Auto Mark/Time Mark Button

26. Mode/Insert Button

27. Bass/Delete Button

28. Enter/Fast Play/Synchro Button

29. Handstrap Attachment Eye

30. Stop/Power Off Button: /:OFF

31. Eject Lever

32. Optical/Line Input Socket

33. Microphone Input Socket

11 12

13 14

REC

SYNC

TOTAL

789

13 14

12345 6

1516

2019

1817

272625 2930313233

21 22

RANDOM

23 24

4 5

7 8

34. Hold Switch

35. Battery Case Connection Terminals

36. Earphones Socket

37. 5V DC Input Socket

38. Rechargeable Lithium-lon Battery Compartment

– 4 –

36 37 38

MD-MS721H

Remote control unit

1. Synchro Recording Indicator

2. Character/Time Information Indicator

3. Record Indicator

4. Repeat Indicator:

5. Random Indicator

6. Disc Mode Indicator

7. Total Track Number Display

8. Track Number Indicator

9. Battery Indicator:

10. Earphones Socket

11. Display/Volume Shuttle Switch

12. Hold Switch

13. Play/Pause/Fast Reverse/ Fast Forward Shuttle Switch

14. Stop/Power Off/Bass/Play Mode Shuttle Switch

Main unit

1. Monaural Long-Play Mode Indicator

2. Record Indicator

3. Level Meter

4. Repeat Indicator:

5. TOC Indocator

6. Battery Indicator:

7. Random Indicator

8. Track Number Indicator

9. Character/Time Information Indicator

10. Synchro Recording Indicator

11. Disc Mode Indicator

12. Disc Name Indicator

13. Track Name Indicator

14. Remaining Recording Time Indicator

15. Total Track Number Display

10 11

12 13

MD-MS722H/MS721H

1 6

SYNC

TOTAL

RANDOM

REC

789

13 14

12345

1415

3 4

6 7

8 9

16. Mode/Insert Button

17. Record/Track Mark Button

18. Fast Reverse/Recording Level Control/

Cursor Button:

19. Play/Pause Button:

20. Fast Forward/Recording Level Control/

Cursor Button:

21. Display/Lowercase Characters Button

22. Volume/Name Select Buttons: --

23. Volume/Name Select Buttons: +

24. Bass/Delete Button

25. Character Button

26. Enter/Fast Play/Synchro Button

27. Edit/Auto Mark/Time Mark Button

28. Handstrap Attachment Eye

29. Stop/Power Off Button: /:OFF

30. Eject Lever

31. Optical/Line Input Socket

32. Microphone Input Socket

33. Hold Switch

34. Battery Case Connection Terminals

35. Earphones Socket

36. 5V DC Input Socket

37. Rechargeable Lithium-lon Battery Compartment

2016

1817

272625 29 30313224

21 22 2319

35 36 37

– 5 –

MD-MS722H/MS721H

Rechargeable battery power

When the rechargeable battery is used for

the first time or when you want to use it

after a long period of disuse, be sure to

charge it fully.

Open the rechargeable battery com-

partment cover.

Insert the rechargeable battery.

Insert the side with the arrow first.

Close the rechargeable battery com-

partment cover.

Plug the AC adaptor into the AC

socket, and then insert the plug on the

AC adaptor lead into the DC IN 5V

socket.

About 4 seconds late r, " " will flash,

and the battery will begin charging.

Battery charging will be complete in 3.0

hours. When the charging is com-

plete, “ ” will go out.

POWER SOURCE

Notes:

After charging has been completed, the

AC adaptor may be left connected.

(For example, when charging at night)

If the rechargeable battery is in the unit,

it will be charged, even whilst operating

the unit. (Float charge)

Do not force open the rechargeable

battery cover too wide.

When the AC adaptor plug is inserted

and a MiniDisc has already been in-

serted, playback may start automati-

cally.

In this case, press the / :OFF button

twice to turn the power off.

This unit can be used with 4 different power sources: a rechargeable battery, an AC

adaptor, a battery case, and a separately available car adaptor (AD-CA20X).

OPEN

Mark

DC IN

To the DC

IN 5V

socket

Insert

securely,

all the

way in.

MS722H Except for UK/

MS721H: AC 220-230V, 50/60 Hz

MS722H For UK: AC 230-240V,

50/60 Hz

Checking the remaining

amount of battery charge

The remaining amount of battery charge is

shown by the battery indicator ( ) dur-

ing operation.

< How to read the battery indicator >

When the battery is completely dis-

charged, the whole battery indicator will

flash. Recharge the battery or replace the

alkaline battery with a new one.

When the battery has run completely out,

“BATT EMPTY” (main unit) and “Lo BATT”

(remote control unit) will appear. Then, the

power will be disconnected automatically.

Notes:

When you are using the unit with a re-

chargeable battery and an alkaline battery

and you want to check the remaining ca-

pacity of the battery, the remaining battery

charge display may not be stable for about

20 seconds after the power is first turned

on.

When the AC adaptor included with this

unit or a separately available car adaptor

is used, the battery indicator will not be

shown.

The number of bars shown in the battery

indicator may increase or decrease, de-

pending on the operation being per-

formed. This is normal.

When the rechargeable battery and the

alkaline battery are used at the same time,

the rechargeable battery is used first, and

then the alkaline battery.

Since the battery indicator shows the re-

maining amount of the particular battery

being used, the number of bars will in-

crease when the unit switches to the alka-

line battery.

CONVENIENT OPERATION OF THE UNIT

Battery indicator

Charging is

needed.

When the battery is

completely charged

When the battery needs charging, it is

impossible to start recording or editing.

RECORDING USING THE OPTICAL DIGITAL CABLE

There are cases where digital

recording may be impossible.

In the following cases digital recording is

impossible, even if you are using digital

cables.

When you attempt to make a new digital

recording from a track that was digitally

recorded on a MiniDisc

● MiniDiscs are designed so that only

first generation digital copies can

made, further digital copies are pre-

vented by the SCMS (Serial Copy Man-

agement System).

Recording

Playback

CD player, MD

player, etc.

Digitally recorded MiniDisc

Digital cable

Recording

Playback

Digital cable

Analogue recording is

possible.

OPERATION MANUAL

– 6 –

MD-MS722H/MS721H

Moisture condensation

In the following cases, condensation

may form inside the unit.

Shortly after turning on a heater.

When the unit is placed in a room

where there is excessive steam or

moisture.

When the unit is moved from a cool

place to a warm place.

When the unit has condensation inside,

the disc signals cannot be read, and the

unit may not function properly.

If this happens, remove the disc.

The condensation should evaporate in

approximately 1 hour. The unit will then

function properly.

TROUBLESHOOTING

If trouble occurs

When this product is subjected to strong

external interference (mechanical shock,

excessive static electricity, abnormal sup-

ply voltage due to lightning, etc.) or if it is

operated incorrectly, it may malfunction. If

such a problem occurs, do the following:

1. Unplug the AC adaptor from the AC

socket.

2. Remove the battery.

3. Leave the unit completely unpowered

for approximately 30 seconds.

4. Plug the AC adaptor back into the AC

socket and retry the operation.

If strange sounds, smell or smoke come

out of the unit or an object is dropped into

the unit, remove the AC adaptor from the

AC socket immediately and contact an au-

thorised SHARP service centre.

Many potential “problems” can be resolved by the owner without calling a service tech-

nician. If something seems to be wrong with this product, check the following before

calling your authorised SHARP dealer or service centre.

PROBLEM CAUSE

The unit does not turn

on.

Is the AC adaptor disconnected?

Is the battery exhausted?

Is the unit in the safety mode?

Has condensation formed inside the unit?

Is the unit being influenced by mechanical shock or by

static electricity?

No sound is heard

from the earphones.

Is the volume set too low?

Is the remote control unit or the earphones plugged

in?

Are you trying to play a MiniDisc with data on it

instead of a MiniDisc containing music?

When the operation

buttons are pressed,

the unit does not

respond.

Is the unit in the safety mode?

Is the battery exhausted?

Is the remote control unit plug or the earphone plug

inserted firmly?

Some sounds are

skipped.

Is the battery exhausted?

Is the unit being subjected to excessive vibration?

The MiniDisc cannot

be ejected.

Has the track number or character information been

written on the disc yet?

Is the unit in the recording or editing mode?

Recording and editing

are impossible.

Is the MiniDisc protected against accidental erasure?

Is the unit connected properly to the other equipment?

Is the AC adaptor unplugged or did a power failure

occur whilst recording or editing?

Is the unit in the safety mode?

Is an optical signal being output from the external

equipment?

Read the operation manual for the external equipment.

Even if the maximum recording

time of a MiniDisc has not been

reached, “DISC FULL” or “TOC

FULL” may be displayed.

When the number of tracks used

reaches the limit, regardless of the

remaining recording time, further

recording will be impossible.

(Maximum number of tracks: 254)

If a MiniDisc has been recorded or

edited repeatedly or if a MiniDisc has

scratches on it, it may not be possible

to record the maximum number of

tracks on it.

Even if the number of tracks and

the recording time have not

reached the limit, “DISC FULL” may

be displayed.

If there are scratches on a disc, the

unit will automatically avoid recording

in those areas. The recording time will

be reduced.

Even if several short tracks are

erased, the remaining recording

time may not show an increase.

When the remaining recording time of

a disc is displayed, short tracks less

than 12 seconds long may not be

included in the total.

Two tracks may not be combined in

editing.

For MiniDiscs on which repeated

recording and editing operations were

performed, the COMBINE function

may not work.

The total of the recorded time and

time remaining on a disc may not

add up to the maximum possible

recording time.

A cluster (about 2 seconds) is

normally the minimum unit of

recording. So, even if a track is less

than 2 seconds long, it will use about

2 seconds of space on the disc.

Therefore, the time actually available

for recording may be less than the

remaining time displayed.

If there are scratches on discs, those

sections will be automatically avoided

(no recording will be placed in those

sections). Therefore, the recording

time will be reduced.

When recorded tracks are played

back using the cue and review

operations, some sounds may be

skipped.

For MiniDiscs on which repeated

recording and editing were performed,

some sounds may be skipped whilst

cueing and reviewing.

A track number can be created in

the middle of a track.

If there are scratches or dust on a

MiniDisc, the track numbers following

that track will be increased by one.

MiniDiscs are recorded using a different system than is used for cassette tapes or DAT

recordings. Therefore, the following conditions may be encountered, depending on how

the disc has been recorded or edited. These are due to system limitations, and should

be considered normal.

MINIDISC SYSTEM LIMITATIONS

– 7 –

MD-MS722H/MS721H

( ): Error messages seen on the re-

mote control.

Error messages Meaning Remedy

BATT EMPTY

(Lo BATT)

The battery run down. Charge the rechargeable battery or

replace the alkaline battery (or use

the AC adaptor for power).

BLANK DISC

(BLANK)

Nothing is recorded. Replace the disc with a recorded

disc.

Can't COPY

(Not REC)

No copy can be made because of

the SCMS copyright system.

Record using the analogue cable.

Can't EDIT

A track cannot be edited. Change the stop position of the

track and then try editing it.

Can't REC

(Not REC)

Recording cannot be performed

correctly due to vibration or shock

in the unit.

Re-record or replace it with another

recordable disc.

Can't WRITE Editing is impossible. Check the number of tracks.

DEFECT

(DEFECT)

The disc is scratched. If the sound you hear is not right,

try recording again.

Replace the disc with another

recordable disc.

Din UNLOCK

(UNLOCK)

Poor connection of the digital cable. Connect the digital cable securely.

DISC ERROR

(E-DISC)

The disc is damaged. Reload the disc or replace it.

DISC FULL

The disc is out of recording space. Replace it with another recordable

disc.

HOLD

(HOLD)

The unit is in the safety mode. Return the HOLD switch to its

original position.

LOCKED

LOCK ERROR

The EJECT lever was moved

during recording or editing.

Turn off the power and remove the

MiniDisc.

NO DISC A disc has not been loaded. Load a disc.

PB DISC

PROTECTED

The disc is write protected.

You tried to record on a playback-

only disc.

Move the write protection knob

back to its original position.

Replace it with a recordable disc.

POWER ?

Improper power is being supplied. Use one of the specified power

sources.

SORRY

(SORRY)

Since a track number is currently

being located or written to, the unit

cannot accept your command.

Wait for a while and try the

operation again.

SYSTEM ERR

(E-SYS)

You have come to the conclusion

that the unit is out of order.

To have it repaired, go to the

distributor where you purchased the

unit.

TEMP OVER

(E-TEMP)

The temperature is too high. Turn off the power, and wait for a

while.

TOC ERROR

(E-TOC)

A large portion of the disc has been

damaged.

Replace it with another recorded

disc.

TOC FULL

There is no space left for recording

character information (track names,

disc names, etc.).

Replace it with another recordable

disc.

Tr. Protect

The track has been protected from

being erased.

Edit the track with the device on

which it was recorded.

U TOC ERROR

(E-UTOC)

A large portion of the disc has been

damaged.

There is an error in the recorded

signal.

Replace it with another recorded

disc.

Erase all of the signal errors, and

then try recording again.

? DISC

(?DISC)

A disc which contains data other

than music was played.

There is an error in the signal from

the disc.

A disc which contains non-music

data cannot be played.

Replace it with another recorded

disc.

ERROR MESSAGES

– 8 –

MD-MS722H/MS721H

Do not allow rise of upper cabinet.

DISASSEMBLY

Cares before disassembling

When assembling the machine after disassembling or

repair, observe the following requirements so as to ensure safety and performance.

1. Remove the batteries from the machine, and take out the mini-disc.

2. When assembling after repair, be sure to restore the initial location of wires. Since the screws are small, incorrect fixing may result in malfunction.

3. When repairing, pay utmost attention to static electricity of ICs.

STEP

REMOVAL

PROCEDURE

1 Bottom Cabinet 1. Battery Cover.........(A1) x1 9-1

2. Screw ..................... (A2) x6

2 Top Cabinet 1. Screw ..................... (B1) x3 9-1

2. Flexble PWB .......... (B2) x2 9-2

3 Main PWB 1. Screw .................... (C1) x2 9-2

2. Flexble PWB ......... (C2) x2

3. Soldering ............... (C3) x4

4 Mechanism Unit

1. Raise the rear part, and remove in the arrow direction.

(Illustration: MD-MS722H)

FIGURE

9-3

(A2)x2 ø1.4x2mm

Bottom Cabinet

(A2)x1 ø1.4x2.5mm

Center Cabinet

Put the fold on the connector, and apply with the felt. Sagging may result in contact with the sheet metal.

Felt

Main PWB

Pull

(A2)x1 ø1.4x2mm

Top Cabinet

Figu re 9-1

Pull

(B1)x2 ø1.4x2mm

(C1)x1 ø1.7x2.5mm

Pull

(C3)x3

(B1)x1 ø1.4x2mm

(A1)x1

(A2)x2 ø1.4x2mm

(B2)x1

(C1)x1 ø1.7x2.5mm

(B2)x1

Pull

ø1.4x2.5mm

Cares when servicing:

Be sure to use the screw with washer (Part code: LX-BZ0822AFFC, Distribution code: 124 970 0187). If a screw of different length is used by mistake, MD ejection may be disabled.

Figure 9-4

INST ALLING THE TOP CABINET

Insert the key flexible PWB at first into the clearance of center cabinet.

(C2)x1* Flexble PWB for optical pickup

(C2)x1

(C3)x1

Top Cabinet

Caution:

Carefully handle the main PWB and flexible PWB. After removing the flexible PWB (*1) for the optical pickup from the connector, do not touch directly the front end of flexible PWB with your hand so as to prevent damage of optical pickup by static electricity.

Figure 9-2

Mechanism Unit

Figure 9-3

Figure 9-6Figure 9-5

– 9 –

MD-MS722H/MS721H

REMOVING AND REINSTALLING THE MAIN PARTS

Remove the mechanism according to the disassembling methods 1 to 3. (See Page 9.)

(A2)x3

ø1.4x2.8mm

How to remove the spindle motor (See Fig. 10-1.)

1. Remove the solder joint (A1) x 1 of flex PWB.

2. Remove the stop (A2) x 3 pcs. and remove the spindle motor.

How to remove the lift motor (See Fig. 10-2.)

1. Remove the solder joint (B1) x 2 of slide motor lead wire.

2. Remove the screw (B2) x 1 pc., and remove the flexible PWB.

3. Remove the screw (B3) x 1, and remove the lift motor.

Note:

Take care so that the motor gear is not damaged. (If the gear is damaged, noise is caused.)

How to remove the sled motor (See Fig. 10-3.)

1. Remove the stop washer (C1) x 1 pc., and remove the drive

gear (C2) x 1 pc.

2. Remove the screw (C3) x 2 pc.

3. Remove the screw (C4) x 2, and remove the sled motor.

Note:

Take care so that the motor gear is not damaged. (If the gear is damaged, noise is caused.)

How to remove the magnetic head (See Fig. 10-4.)

1. Remove the screw (D1) x1 which connects the magnetic

head to the head relay flex PWB, and remove the soldering joint (D2) x2 pcs.

Note:

Mount carefully so as not to damage the magnetic head.

(B1)x2 Remove the solder joint

Lift Motor

Stop Washer

(C1)x1

Spindle Motor

Mecha Flexble PWB Solder joint (A1)x1

Figure 10-1

(B3)x1

ø1.4x5.5mm

(B2)x1

ø1.4x1.5mm

Figure 10-2

(C3)x2 ø1.4x1.2mm

MD Mechanism

How to reinstall the optical pickup unit (See Fig. 10-5.)

1. Remove the screws (E1) x 1 pcs.

2. Slowly raise the optical pickup.

(E1)x1 ø1.7x2.5mm

Shaft

Pickup Unit

Figure 10-5

– 10 –

Shaft

Pickup Unit

Shaft

Pickup Unit

Drive Gear

(C2)x1

Sled Motor

(C4)x2 Mecha Flexble PWB Solder joint

Figure 10-3

Magnetic Head

Solder joint (D2)x2

(D1)x1 Ø1.4x1.5mm

Figure 10-4

MD-MS722H/MS721H

Test disc

ADJUSTMENT

MD adjustment needs two types of disc, namely recording disc (low reflection disc) and playback-only disc (high reflection disc).

Type

1 High reflection disc MMD-110 (TEAC Test MD) 88GMMD-110 2 Lowreflection disc MMD-212 (TEAC Test MD) 88GMMD-212 3 Low reflection disc Recording minidisc UDSKM0001AFZZ

Test disc Parts No.

Note: Use the low reflection disc on which music has been recorded.

Entering the TEST mode

1. Setting at port (in standby state, disc-free state or power nonconnected state)

(1) Set the port as follows. TEST1 : "Low" TEST0 : "High" (2) Press the PLAY button in the standby state (it is allowed to insert the disc or to connect the power supply). (3) Test Mode STOP [ _ T E S T _ ]

2. Setting by special button operation (in standby state)

(1) Holding down the DISP button and ENTER button, press the PLAY button. (2) Normal mode setting initialization (BASS setting, VOL setting, etc.) (3) Indication of microcomputer version for one second [ 7 0 2 A f X ] (Serial No. 811XXXXX)

[ 9 0 8 A f X ] (Serial No. 812XXXXX~)

Destination

Microcomputer version (4) Whole LCD lighting for 2 seconds (5) Test Mode STOP [ _ T E S T _ ] *When the PLAY button is pressed during indication (3) and (4), the process proceeds to (5).

EEPROM version

Leaving the TEST mode

(1) Press the STOP button in the TEST mode stop state or version indicating state or whole LCD lighting state. (2) EEPROM rewrite-enable area updating, adjustment error setting (so as to adjust all the items when the power supply is turned

on in the normal mode)

(3) Change to standby state

Shipping setting method

Holding down simultaneously the VOLUME-DOWN key and PLAY key of the set unit without disc, supply the power from the DC IN plug. After the indication "INIT" -> "BYE OK" disappears, release the power supply of DC IN.

Test Mode

1. AUTO 1 Mode • Perform preliminary automatic adjustment.

2. AUTO 2 Mode

3. MANUAL 1 Mode

4. MANUAL 2 Mode

5. RESULT 1 Mode

6. RESULT 2 Mode

7. TEST-PLAY Mode

• If the combination of mechanism and pickup PWB has been changed, be sure to start from

AUTO1.

• Perform ATT (attenuator) automatic adjustment.

• Perform continuous playback (error rate display, jump test)

• Temperature is displayed. (Updating in real time)

• Seeing the displayed adjustment value, perform preliminary manual adjustment. (Error rate indication, jump test)

• Temperature is displayed. (Updating in real time)

• Seeing the displayed adjustment value perform manfully the preliminary adjustment.

(Error rate indication, jump test)

• Continuous playback is performed

(error rate display, jump test).

• The value adjusted in AUTO1 or MANUAL1 is

indicated.

• (Execution in servo "OFF" state").

• The value adjusted in AUTO 2 or MANUAL 2 is

indicated.

• Adjustment value is changed manually.

(error rate display, jump test).

• Continuous playback from the specified address

is performed.

• 1 line, 10 lines or 400 lines manual jump is performed.

• C1 error rate display (pit section), ADIP error rate display (groove section)

• The temperature correction is performed only when servo start is performed, but the posture correction is not performed during continuous playback.

8. TEST-REC Mode

9. NORMAL Mode

10. DIGITAL INPUT Mode

11. ERROR INFORMATION Mode • Error information is initialized

12. EE-PROM Mode

13. INNER Mode

• Continuous record from the specified address is performed.

• Change of record laser output(servo gain is also changed according to laser output).

• The temperature correction is performed only when servo start is performed, but the posture correction is not performed during continuous recording.

• The mode is changed from the TEST mode to the normal mode without adjustment.

• In the normal mode the internal operation mode, memory capacity, etc. areindicated.

• In the normal mode both temperature correction and posture correction are perfomed.

• Digital input information is displayed.

• Error information is displayed.

• Factors of digital servo are changed manually. (Each servo is turned on individually.)

• Cut-off frequency of BASS1, BASS2 and BASS3 is selected manually.

• Temperature detection terminal voltage is measured, and the reference value is set.

• Defaults are selected and set.

• Setting of EEPROM protect area is updated. (In case of protect releasing)

• Determine the position where the INNER switch is turned on. (only high reflection disc).

• The temperature correction is performed only when servo start is performed, but the posture correction is not performed.

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MD-MS722H/MS721H

Operation in each TEST mode

1. AUTO1 Mode

• When the STOP button is pressed while the AUTO1 menu appears or during automatic adjustment, the mode changes to the TEST mode stop state. At this time the adjustment value is not output.

• Be sure to adjust, using the specified disc MMD-212.

At this time release the EEPROM (IC402) protection. (Refer to EEPROM write procedure.)

• Adjustment NG; Adjustment item out of range, focus ON failure, and adjustment error

• When the PLAY button is pressed while ADJ. OK is displayed, AUTO2 is executed.

2. AUTO2 Mode

• When the STOP button is pressed while the AUTO2 menu appears or during automatic adjustment, the mode changes to the TEST mode stop state. At this time the adjustment value is not output.

• Adjustment NG; Adjustment item out of range, and adjustment error.

3. MANUAL1 Mode

• Adjustment item to be made in AUTO1 mode is performed manually.

• When the VOL UP button is pressed during adjustment, the setting increases, and the new setting is output.

• If the VOL DOWN button is pressed during adjustment, the setting decreases and the new setting is output.

• If the VOLUP/DOWN button is held down, the setting changes continuously with 100 ms cycle.

• If the setting is within the allowable range, the RANDOM display lights.

• When the STOP button is pressed during MANUAL1 MENU or measurement or adjustment, the state is changed to the TEST mode stop state.

4. MANUAL2 Mode

• Adjustment item to be made in AUTO2 mode is performed manually.

• When the VOL UP button is pressed during adjustment, the setting increases, and the new setting is output.

• If the VOL DOWN button is pressed during adjustment, the setting decreases and the new setting is output.

• If the VOLUP/DOWN button is held down, the setting changes continuously with 100 ms cycle.

• If the setting is within the allowable range, the RANDOM display lights.

• When the STOP button is pressed during MANUAL2 MENU or measurement or adjustment, the state is changed to the TEST mode stop state.

• When the PLAY button is pressed in B-ATT set state, the mode is changed to the continuous playback mode.

• As for operation during continuous playback refer to "TEST-PLAY mode explanation".

5. RESULT1 Mode

• The measurement value and set value of adjustment items for AUTO1 and MANUAL 1 are displayed.

• If the VOL UP button is pressed during setting indication, the setting increases. If the VOL DOWN button is pressed, the setting reduces.

And then the new setting is stored in the RAM.

• When the VOL UP/DOWN button is held down, the setting changes continuously, one cycle being 100 ms.

• If the STOP button is pressed during RESULT1 menu or measurement value indication or set value indication, the state is changed to the TEST mode STOOP state.

6. RESULT2 Mode

• The measurement value and set value of adjustment items for AUTO2 and MANUAL 2 are displayed.

• If the VOL UP button is pressed during setting indication, the setting increases. If the VOL DOWN button is pressed, the setting reduces.

And then the new setting is stored in the RAM.

• When the VOL UP/DOWN button is held down, the setting changes continuously, one cycle being 100 ms.

• If the STOP button is pressed during RESULT2 menu or measurement value indication or set value indication, the state is changed to the TEST mode STOOP state.

7. TEST-PLAY Mode

•When the STOP button is pressed while the TEST-PLAY menu appears, or in TEST-PLAY or continuous playback mode, the mode changes to the TEST mode stop state.

• When the PLAY button is pressed while the TEST-PLAY menu appears,continuous playback is initiated from the current pickup position.

• Whenever the DISP button is pressed in the TEST-PLAY mode, the address changes as follows.

• Whenever the BASS key is pressed in the TEST-PLAY mode, the digit which is changed by the SKIP UP/DOWN button changes as follows.

• When the SKIP UP button is pressed in the TEST-PLAY mode, the digit of address specified by the BASS button is set to +1h. (0 to F)

• When the SKIP DOWN button is pressed in the TEST-PLAY mode, the digit of address specified by the BASS button is set to -1h. (0 to F) * When the SKIP UP/DOWN button is held down, the setting changes continuously, one cycle being 100 ms.

• When the BASS button is pressed in the continuous playback mode, the number of jump lines changes as follows.

* After the number of jump lines is indicated for one second, the address indication is restored. [ T R _ ]

• When the SKIP UP button is pressed in the continuous playback mode, the specified number of lines is jumped in the FWD direction.

• When the SKIP DOWN button is pressed in the continuous playback mode, the specified number of lines is jumped in the REV direction. * When the SKIP UP/DOWN button is held down, jump is repeated every approx. 100 ms.

0050 — 03C0 — 0700 — 08A0 — 0050 —

005

0 — 0050 — 0050 — 0050 — 0050 —

1 — 10 — 384 — 1

– 12 –

MD-MS722H/MS721H

•Whenever the DISP button is pressed in the continuous playback mode, the indication changes as follows. * Pit section

Continuous playback (SUBQ address indication) [ S Q ]

Continuous playback (C1 error indication) [ C E ]

Continuous playback (SUBQ address indication) [ S Q ]

* Groove section

Continuous playback (ADIP address indication) [ A P ]

Continuous playback (C1 error indication) [ C E ]

Continuous playback (ADIP error indication) [ A E ]

Continuous playback (ADIP address indication) [ A P ]

8. TEST-REC Mode

• When the STOP button is pressed while the TEST-REC menu appears, or in the TEST-REC mode or continuous record mode, the mode changes to the TEST mode stop state.

• When the PLAY button is pressed while the TEST-REC menu appears, the continuous record is initiated from the current pickup position.

• Whenever the DISP button is pressed in the TEST-REC mode, the address changes as follows.

0050 — 03C0 — 0700 — 08A0 — 0050 —

• Whenever the BASS button is pressed in the TEST-REC mode, the digit which is changed by the SKIP UP/DOWN button changes as follows.

0050 — 0050 — 0050 — 0050 — 0050 —

• When the SKIP UP button s pressed in the TEST-REC mode, the digit of address specified by the BASS button is set to +1h.(0 to F)

• When the SKIP DOWN button is pressed in the TEST-REC mode, the digit of address specified by the BASS button is set to -1h. (0 to F)

* When the SKIP UP/DOWN button is held down, the setting changes continuously, one cycle being 100 ms.

• When the VOL UP/DOWN button is pressed in the TEST-REC mode or continuous record mode, the laser record power changes. (Servo gain changes also according to record power.) * After the laser record power is indicated for one second, the address indication is restored.

• : Address

• : Laser power cord

• Operation is disabled if the premastered disc or disc is in miserase-protected state.

[ R P W ]

9. NORMAL Mode

• When the STOP button is pressed while the NORMAl menu appears, the mode changes to the TEST mode stop state.

• Indication during operation Indication of memory capacity on main unit LCD [ ] + Level meter

: Internal mode : Address (Cluster section)

• Selection of sound volume, BASS, etc. is possible (without indication)

• Recording is also possible.

: Address (Sector section)

10. Digital input display Mode (Din Mon)

• When the STOP button is pressed while the digital input indication menu appears or during digital input information indication, the mode changes to the TEST mode stop state.

• In case of analog input or digital input unlocking the indication data is _.

11. Error data display Mode

• Reversing when SKIP DOWN button is pressed

• When the STOP button is pressed while the error data indication menu appears or during error data indication, the mode changes to the TEST mode stop state.

• Error data 0 is the latest error.

• Error which occurred in the TEST mode is also stored in the memory.

• When the DISP button is pressed while the error data indication menu appears, the error data is initialized. [ C L E A R _ ]

•

: Error Code

Explanation of error history code

12h : RF side FG, TG, and TCRS adjustment termination failure 13h : Adjustment servo retraction excessive retrial 16h : C. IN detection time-over 17h : A, B, E, F, and TCRSO offset measurement value out of

tolerable range 21h : Focus retraction completion allowable time-over 23h : Track search completion allowable time-over 24h : Disc linear speed measurement failure 32h : P-TOC read failure 42h : U-TOC read failure 44h : U-TOC write data write disabled/read check error

52h : SD write data write disabled 71h : Pickup position initialization time-over 72h : EEPROM data read check sum error 73h : Record head drive disabled (by EJECT lever) 82h : Power overvoltage detection 91h : Ambient temperature is higher that the allowable tempera-

ture.

– 13 –

MD-MS722H/MS721H

13. INNER Mode

• when the STOP button is pressed on the INNER menu (SQ______ ), the state is changed to the TEST mode STOP state.

• : Address

EEPROM (IC402) writing procedure

1. Procedure to replace EE-PROM and write initial value of microcomputer in EEPROM

(1) Replace EEPROM. (2) Deprive EEPROM of protection (connect the pins 8 and 6 of IC402). (3) Refer to the latest EEPROM data list. (4) Press the Display/Lower-case Character button, Enter/Synchro button and Play/Pause button to start the test mode. (5) Version display

[ V e r . ]

Destination EEPROM version (C ~ Z)

Microcomputer ROM version (6) The whole LCD lights. (7) Test mode stop state

[ T E S T ]

(8) Press the "BASS" button, and press twice the "SKIP DOWN" button.

[ E E P R O M ]

(9) Perform the operation to display "EEPROM SETTING MODE CHART", compare the EEPROM DATA LIST with the display,

and set according to the EEPROM DATA LIST with the VOL UP or VOL DOWN key.

(10)

Set the temperature reference. (Refer to the Temperature Reference Setting Method.)

(11)

Set according to the EEPROM DATA LIST.

(12)

Press the Stop button.

[ T E S T ]

(13)

Press the Stop button.

(14)

After data is written in EEPROM, turn off power .

(15)

Restore protection of EEPROM (Disconnect connection made in Step (2) above).

2. Temperature reference setting method

[1] Measurement, calculation and setting procedure

(1) Set the TEST mode.

• Set TEST 1, 0 = '01', and turn on power (or set PLAY ON in standby state). (2) Start the EEPROM mode 'Temp' menu.

• Key operation in order of BASS, SKIP-DOWN x 2 times, PLAY, PLAY in the test mode STOP state.

• 'TM$$%%' is displayed. ($$= Temperature code, %% = Temperature reference) (3) Once press SKIP-UP, and determine the displayed microcomputer TEMP input AD value.

• 'TPin##' is displayed. (## = TEMP input AD value) (4) At the ambient temperature, determine the temperature corrected value from the temperature measurement value

correction table.

(5) Determine the temperature reference, using the following formula.

• Temperature reference = Microcomputer TEMP input AD value + Temperature corrected value

• When data is written into EEPROM, the value shown adove is recorded at the specified address.

[2] Temperature measurement value correction table

Ambient temperature Temperature correction

+ 9oC ~ +11oC - 05h + 10.0oC +12oC ~ +14oC - 04h + 12.7oC +15oC ~ +16oC - 03h + 15.4oC +17oC ~ +19oC - 02h + 18.2oC +20oC ~ +22oC - 01h + 20.9oC +23oC ~ +24oC ± 00h + 23.6oC +25oC ~ +27oC + 01h + 26.3oC +28oC ~ +30oC + 02h + 29.0oC +31oC ~ +33oC + 03h + 31.8oC

[3] Power IC VREF feed control output

• After automatic adjustment the temperature code is read. If it is within the following range, OK.

Ambient temperature Temperature correction

- 9oC ~ +10oC 08h + 0.5oC

+ 3oC ~ +21oC 07h + 12.5oC +15oC ~ +33oC 06h + 23.6oC +26oC ~ +43oC 05h + 35.0oC

Center temperature

– 14 –

EEPROM DATA LIST (EEPROM version f)

TEMP setting

Item display Set values

T M _ _ Calculate values

Fucus setting

Item display Set values

F G _ _ 6 3 H F F 1 _ 7 0 H F F 2 _ E 8 H F Z H _ E D H F L n _ 0 9 H D J G _ 1 4 H F L V _ 2 0 H W T f _ 2 0 H F S S _ A A H

Tracking setting

Item display Set values

T G _ _ 2 6 H T F 1 _ 7 0 H T F 2 _ E 0 H T F S _ 0 0 H T B o _ 2 B H T B t _ 1 4 H T K o _ 2 B H T K t _ 1 2 H T D o _ 6 7 H T D t _ 3 4 H S C o _ 0 0 H S C t _ 4 0 H S C m _ 5 3 H C L p _ 1 8 H C L r _ 2 8 H J P I _ 0 0 H K 1 0 _ 6 5 H

Spindle setting

Item display Set values

S P G _ 1 4 H S P i _ A A H S P m _ 7 9 H S P o _ 4 F H S P 1 _ 1 0 H S P 2 _ 6 0 H S P 3 _ F 2 H S P 4 _ F 2 H S P 5 _ 1 0 H S P D _ 6 1 H S P K _ 8 B H

BASS setting

Item display Set values

B S 1 _ 0 0 H B S 2 _ 2 D H B S 3 _ 4 B H

MD-MS722H/MS721H

Sled setting

Item display Set values

S L G _ 6 D H S L 2 _ 2 0 H S L M _ 4 F H S L V _ 3 6 H S K k _ 4 3 H S K t _ 5 4 H S K m _ 4 D H W T m _ 2 4 H M V 1 _ 4 A H M V 2 _ A A H S R V _ 0 0 H

ADJ. SET setting

Item display Set values

C O K _ A 0 H F A T _ C 0 H T A T _ 3 E H C A T _ 2 0 H F A B _ E 0 H

EQ. SET setting

Item display Set values

H Q 1 _ 9 0 H H Q 2 _ 9 0 H H S G _ 1 1 H H S O _ F D H L Q 1 _ 9 0 H L Q 2 _ 9 0 H L S G _ 1 1 H L S O _ 0 0 H G Q 1 _ 9 8 H G Q 2 _ 8 4 H G S G _ 1 1 H G S O _ 0 0 H

Control setting

Item display Set values

C T 0 _ 0 5 H C T 1 _ 9 5 H C T 2 _ 4 0 H C T 3 _ 3 0 H R C 0 _ C 0 H R C 1 _ F E H S Y C _ A 6 H P W C _ 1 2 H P W L _ 6 6 H D R 1 _ 4 9 H D R 2 _ 4 9 H I N 1 _ D 4 H I N 2 _ 7 1 H I N H _ 6 4 H D R H _ 7 4 H P L E _ 9 6 H R C E _ 5 4 H E L T _ 7 2 H S L T _ 7 3 H S P M _ 0 0 H M S L _ 0 0 H U S 0 _ 0 0 H U S 1 _ 0 0 H U S 2 _ 0 0 H

– 15 –

MD-MS722H/MS721H

: Test Mode STOP

: Pre-autoadjustment menu

: ATT autoadjustment menu

: Continuous record menu

: EEPROM setting menu

: INNER switch position measurement menu

BASS

T E S T

Slide external

periphery move

Slide internal

periphery move

Tset Mode Menu

Test Mode Change Chart

A U T O 1

A U T O 2

SKIP UP SKIP DOWN

SKIP DOWN

SKIP UP SKIP DOWN

T R E C

SKIP UP SKIP DOWN

: Continuous playback menu

T P L A Y

SKIP UP SKIP DOWN

: Digital input signal monitor menu

D i n M o n

SKIP UP SKIP DOWN

E E P R O M

SKIP UP SKIP DOWN

I N N E R

SKIP UP

SKIP DOWN

SKIP UP

* When the [STOP] key is pressed in specific menu, the "TEST MODE STOP" state is set.

* When the [PLAY] key operation is performed in the specific menu, the operation of this

menu is executed.

: Preadjustment value check menu

R S L T 1

: ATT adjustment value check menu

R S L T 2

: Pre-manual adjustment menu

M A N U 1

: ATT manual adjustment menu

M A N U 2

: Error history display menu

E D A T A

: Test mode normal playback menu

N O R M A L

: Preautomatic Adjustment menu

: Preadjustment error (adjustment value output)

: During preadjustment adjustment

Adjustment error

Normal end

: Preadjustment normal end (adjustment value output)

: During ATT automatic adjustment

PLAY

A U T O 1

Preautomatic Adjustment

A D J . O K

A D J . N G

A T 2

A T 1

* When the [STOP] key is pressed in specific menu, the "TEST MODE STOP" state is set.

* " " represent the adjustment number as follows.

0 0 : Innermost periphery move

0 2 : ABEF offset tentative measurement

0 4 : RF side focus gain coarse adjustment

0 5 : Focus ATT tentative setting

0 6 : RF side bit section tracking gain adjustment

0 7 : COUT level setting for pit section adjustment

0 8 : External periphery move

0 9 : RF side groove section tracking gain adjustment

1 0 : COUT level setting for groove section adjustment

1 1 : RF side TCRS gain adjustment

1 2 : Tracking ATT initial setting

1 3 : RF side focus gain minor adjustment

1 4 : Focus ATT initial setting

1 5 : S gain "High" ABEF offset measurement

1 6 : TCRS offset measurement

1 7 : S gain "Low" ABEF offset measurement

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