Sharp MDS301MK Service Manual

MD-S301MK

SERVICE MANUAL

No. S8865MDS301MK

MD-S301MK

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

This Service Manual is for the MD-S301MK, which is a minormodification
model of the MD-S301, This manual, therefore, describes only the changed
points from the service manual. Please refer to the MD-S301 service manual
(No. S1801MDS301//) together with this manual.

MD-S301

Page

INSTALLING THE TOP CABINET .................................. 7

TEST MODE MENU ...................................................... 10

WAVEFORMS OF MD CIRCUIT................................... 31

TROUBLESHOOTING................................................... 32

FUNCTION TABLE OF IC ............................................. 36

CONTENTS

Page

SPECIFICATIONS ................................................................................................................................................................. 2

BATTERY DISPOSAL............................................................................................................................................................. 2

NAMES OF PARTS ............................................................................................................................................................... 3

OPERATION MANUAL .......................................................................................................................................................... 4

QUICK GUIDE ........................................................................................................................................................................ 6

DISASSEMBLY...................................................................................................................................................................... 7

REMOVING AND REINSTALLING THE MAIN PARTS......................................................................................................... 8

ADJUSTMENT ....................................................................................................................................................................... 9

BLOCK DIAGRAM ................................................................................................................................................................ 11

SCHEMATIC DIAGRAM/WIRING SIDE OF P.W.BOARD.................................................................................................... 12

VOLTAGE ............................................................................................................................................................................. 17

NOTES ON SCHEMATIC DIAGRAM ................................................................................................................................... 18

PARTS GUIDE/EXPLODED VIEW

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-S301MK

FOR A COMPLETE DESCRIPTION OF THE OPERATION OF THIS UNIT, PLEASE REFER
TO THE OPERATION MANUAL.

SPECIFICATIONS

General
Power source:

Power consumption:7 W (AC adaptor)
Output power: RMS; 10 mW (5 mW + 5 mW)

Charging time: Approx. 3.5 hours

Battery life:

When using the
rechargeable battery
(fully charged)
included with the unit

Approx. 8 hours Approx.3.5 hours Approx. 11.5 hours

Volume level: "VOL 15"
The above values are the standard values when the unit is
charged and used at an ambient temperature of 68 ˚F (20 ˚C).
The playing time when using an alkaline battery may be different,
depending on the type and manufacturer of the battery and on the
operating temperature.

DC 3.6 V (rechargeable lithium-ion battery x 1)
DC 5 V (AC adaptor)
AC 120V, 60 Hz
DC 1.5 V: Optionally available battery case,

DC 4.5 V: Optionally available car adaptor,

(0.2 % T.H.D.)
(When using the AC adaptor included with

the unit)

When using one, commer­cially available, high
capacity, "AA" size, alkaline
battery (in the optionally
available battery case)

AD-S30BC(commercially available,
"AA" size, alkaline battery x 1)

AD-CA20X(
DC negative
system)

for cars with a 12-24V

ground electrical

When using one, commer­cially available, high
capacity, "AA" size, battery
with the rechargeable
battery (fully charged)

Output level:

Specified

output

Headphones — 5 mW + 5 mW 32 ohms
LINE 250 mV (-12 dB) — 50 kohms

Dimensions: Width: 3-7/16" (87 mm)

Height: 31/32" (24 mm)
Depth: 3-3/32" (78 mm)

Weight: 0.43 lbs. (192 g) with rechargeable

battery

Output socket: Headphones (impedance: 19 ohms)/

remote control unit

Maximum

output level

Load

impedance

MiniDisc Player

Type: Portable MiniDisc player
Signal readout: Non-contact, 3-beam semi-conductor

Audio channels: 2
Frequency response: 20 - 20,000 Hz (± 3 dB)
Rotation speed: Approx. 400 - 900 rpm
Error correction: ACIRC (Advanced Cross Interleave

Coding: ATRAC (Adaptive TRansform
D/A converter: 1 bit

Sampling frequency: 44.1kHz
Modulation system: EFM (Eight to Fourteen Modulation)
Wow and flutter: Unmeasurable (less than ±0.001%

laser pick-up

Reed-Solomon Code)
Acoustic Coding)

W.peak)

Specifications for this model are subject to change without
prior notice.

BATTERY DISPOSAL

Contains nickel cadmium (or sealed lead) battery.Must be
recycled or disposed of properly.Remove the battery from the
product and contact federal or state environmental agencies
for information on recycling and disposal options.

– 2 –

NAMES OF PARTS

Main unit

1. Volume Buttons: +, –

2. Stop/Power Off/Charge Button: :OFF

3. Power Indicator

4. Fast Reverse Button:

5. Play/Fast Forward Button:

6. 5V DC Input Socket

7. Eject Lever

8. Hold Switch

9. Battery Case Connection Terminals

10. Headphones Socket

11. Rechargeable Lithium-lon Battery Compartment

MD-S301MK

1

2

5
6

3

7

8

10

Remote control unit

1. Character/Time Information Display

2. Disc Mode Indicator

3. Total Track Number Display

4. Track Number Indicator

5. Battery Indicator:

6. Repeat Indicator:

7. Random Indicator

8. Headphones Socket

9. Hold Switch

10. Play Mode Button

11. Volume Buttons: +, –

12. Bass Button

13. Display Button

14. Play/Pause Button:

15. Stop/Power Off Button:

16. Fast Reverse/Fast Foward Buttons:

9

8
9

10

11

2

1

TOTAL

3

4

1

RANDOM

5

11

6
7

13

14
15

– 3 –

16

12

MD-S301MK

■ 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.

1Open the rechargeable battery com-

partment cover.

2Insert the rechargeable battery.

● Insert the side with the arrow first.

3Close the rechargeable battery com-

partment cover.

4Plug the AC adaptor into the AC outlet,

and then insert the plug on the AC

adaptor cord into the DC IN 5V jack.

5Press the ■:OFF button to begin charg-

ing.

● The POWER indicator will flash, and

the battery will begin charging.

● Battery charging will be complete in 3.5

hours. When the battery is fully

charged, the POWER indicator will go

out.

1

2

POWER SOURCE

Notes:

● After charging is complete, the AC

adaptor may be left connected.

(For example, when charging at night)

● The battery will not be charged when-

ever the power to the main unit is

turned on.

● If the operation in step 5 is performed

without inserting the rechargeable bat-

tery, the POWER indicator will flash for

5 seconds. This is normal.

● Do not force open the rechargeable

battery cover too far.

● Do not attach the optionally available

battery case when charging the internal

battery.

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

adaptor, an optionally available battery case (AD-S30BC), and an optionally available car

adaptor (AD-CA20X).

OPEN

OPEN

Mark

To the

DC IN 5V

jack

AC 120V, 60 Hz

OPEN

OFF

POWER

5

Insert

securely,

all the way

in.

4

■ Checking the remaining

amount of battery charge

The remaining amount of battery charge is

shown by t he battery indicator ( ) on

the remote control display during oper-

ation.

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 completely run

out, “Lo BATT” will appear in the dis-

play. Then, the power will be discon-

nected automatically.

Notes:

●

When the AC adaptor included with this

unit or an optionally 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 al-

kaline battery.

CONVENIENT OPERATION OF THE UNIT

Battery

indicator

Charging is

needed.

When the battery is

completely charged

OPERATION MANUAL

– 4 –

MD-S301MK

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

outlet.

2. Remove the battery.

3. Leave the unit completely unpowered

for approximately 30 seconds.

4. Plug the AC adaptor back into the AC

outlet 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 outlet immediately and contact an au-

thorized Sharp service centre.

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

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

your authorized SHARP dealer or service center.

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 headphones.

Is the volume set too low?

Is the remote control unit or the headphones 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 headphone plug

inserted firmly?

Has condensation formed inside the unit?

Is the unit being influenced by mechanical shock or by

static electricity?

Some sounds are

skipped.

Is the battery exhausted?

Is the unit being subjected to excessive vibration?

TROUBLESHOOTING

When an error message is displayed on the display, proceed as follows:

Display Meaning Remedy

BLANK

Nothing is recorded. Replace the disc with a

recorded disc.

E-DISC

The disc is damaged or

the music information is

not written properly on the

disc.

Replace the disc.

E-SYS

The unit is malfunctioning

and will require service.

For service, contact your

local Sharp authorized

servicer.

E-TEMP

The temperature is too

high.

Turn off the power, and

wait for a while.

E-TOC

E-UTOC

The disc is damagad. Replace the disc.

Lo BATT

The battery has run down. Charge the rechargeable

battery or replace the

alkaline battery (or use

the AC adaptor for power).

No DISC

A disc has not been

loaded.

Load a disc.

POWER?

Improper power is being

supplied.

Use one of the specified

power sources.

?DISC

There is an error in the

signal from the disc.

Replace the disc.

ERROR MESSAGES

– 5 –

MD-S301MK

PORTABLE MINIDISC PLAYER Quick-Guide

MD-S301

MK

Guía rápida

AC power

Alimentación de CA

AC 120V, 60Hz
To an AC outlet

120V CA, 60Hz
A un tomacor rien te de CA

To the DC IN 5V jack

Al enchufe DC IN 5V

Alkaline battery power

Alimentación de la pila alcalina

1

• One alkaline battery
(LR6, “AA” size)

•

Una pila alcalina
(tamaño “AA”, LR6)

2

RELEASE LOCK

• Battery is not i ncl uded .

•

La pila no est á i n cl uid a.

Back of the M D pl ayer

Parte trasera del reproductor de minidiscos

Rechargeable battery power

Alimentación de la batería recargable

1

The optio nally avail able a lkali ne
battery case

La caja de la pila alcalina
disponible opcionalmente

Press the ■:OFF

3

2

OPEN

Volume Tone

Volumen Tono

OPEN

Sound control

Control del sonido

Volume level

Nivel de vol ume n

OPEN

AC 120V, 60Hz
To an AC outlet

120V CA, 60Hz
A un tomacor rien te de CA

(1) BASS 1
(2) BASS 2
(3) BASS 3
(4) BASS OFF

BASS

(1) BASS 1

(2) BASS 2
(3) BASS 3

● The volume level can be
adjusted from “0” to “30”.

●

El nivel de vol umen pued e
ajustarse desd e “0” a “30 ”.

(4) BASS OFF

4

button to begin
charging .

Pulse el bo tón

■:OFF

para iniciar

la carga.

Bass is emphasized a little.
Bass is emphasized more.
Bass is emphasized still more.
Bass emphasis is canceled.

Los graves se acentúan un
poco.

Los graves se acentúan más.
Los graves se acentúan toda-

vía más.
La acentuación de los graves

se cancela.

Loading and playing a MiniDisc

Connection

Connection

Inserción y reproducción de un minidisco

Conexión

Conexión

1

2

■ APSS

(Auto Program Search System)

■

APSS

(Sistema de bús queda
automática de programas)

■ Random play or Repeat play

■

Reproducción aleatoria o

reproducción repe tida

PLAY MODE

OFF

Track name
Nombre de pista

To move to the beginning of the next track:

Press the / ( ) button during playback.

To re-start the track being played:

Press th e butto n dur ing play back .

Para pas ar al pr inc ipi o de la pi sta sigu ient e:

Pulse el botó n

Para reiniciar la pista que se está reproduciendo:

Pulse el botón durante la reproducción.

During playback or while in the stop mode, press the PLAY
MODE but ton r epea ted ly to sele ct t he play back mod e.

..........

RANDOM

.............

.............

1

.........

No display

Durante la reproducción o en el modo de parada, pulse repeti­damente el botón PLAY MODE para seleccionar el modo de
reprod ucción.

..........

RANDOM

.............

.............

1

...

Sin visualización

/()

durant e l a r e prod uc ci ó n.

Random play
Repeat play of all of the tracks
Repeat play of a single track
Normal playback

Reproducción aleatoria
Reproducción repetida de todas las pistas
Reproducción repetida de una sola pista

Reproducción normal

■ Important

●Do not wear your headphones when you are cross-

ing stree ts or near traff ic.

● Do n ot us e yo ur he ad phon es wh il e driv in g a mo t or
vehicle, it may create a dangerous traffic hazard
and may be illegal. Remember to obey all of the
safety rules in your area.

●Do not play the unit at a high volume. Hearing
experts advise against extended play at high vol­ume levels.

●If you exper ience ring ing i n your e ars, reduce the
volume or discontinue use.

■

Importante

●

No se ponga auriculares cuando atraviese calles ni
cuando esté cerca del tráfico.

●

No emplee los auriculares mientr as conduce un
vehículo, porque puede cr ear situac iones peligr o­sas en el tráfico y puede ser ilegal. Recuerde que
debe respetar las reglas de seguridad de su zona.

●

No reproduzca sonido en el aparato a altos niveles
de volum en. Lo s exper tos di cen que es per judic ial
la repr oducc ión con tinuada a alto s nivel es de vol ­umen.

●

Si nota timbres en los oídos, reduzca el volumen o
no utilice el aparato.

■ Volume setting

Reduce the volume before starting to play. MiniDiscs,
compared to ordinary cassette tapes, have very little
noise. If the volu me is adjust ed according to your
usual exp ectations of noise, you may damage your
hearing due to the high volume.

■

Ajuste del volume n

Reduzca el volumen antes de iniciar la reproducción.
Los mínidiscos, en compara ción con las cintas de
casete normales, tienen muy poco ruido. Si se ajusta
el volume n de ac ue rdo co n el ruido que p ue de es pe r­arse nor malment e, podría dañar se los oídos debido
al alto vol umen .

– 6 –

DISASSEMBLY

MD-S301MK

Caution on Disassembly

Follow the below-mentioned notes when disassembling
the unit and reassembling it, to keep it safe and ensure
excellent performance:

1. Take the battery and minidisc out of the unit.

2. When disassembling the machine, be sure to withdraw
the power plug from the socket in advance.

3. When disassemble the parts, remove the nylon band or
wire holder as necessary.

To assemble after repair, be sure to arrange the wires as

they were.

If a screw of different length is fitted to the MD mecha-

nism (the screw of the part to be fitted to the MD
mechanism chassis), it may contact the optical pickup,
resulting in malfunction.

4. When repairing, pay due attention to electrostatic charges
of IC.

STEP

REMOVAL

1 Bottom Cover 1. Battery Cover.........(A1) x1 7-1

2 Top Cabinet 1. Screw.....................(B1) x4 7-1

3 Main PWB 1. Screw .................... (C1) x1 7-2

4 Mechanism Unit 1. Lift the back side, and 7-3

PROCEDURE

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

2. Flexible PWB ........ (B2) x1 7-2

2. Flexible PWB ........ (C2) x2

3. Soldering ............. (C3) x3

remove in the arrow
direction.

FIGURE

Note:

Carefully handle the main PWB and flexible PWB.
So as to prevent electrostatic damage of optical pickup after
removing the flexible PWB (*1) for optical pickup from the
connector, wrap the front end of flexible PWB in conductive
aluminum foil.

(B1)x2
ø1x2.5mm

Center
Cabinet

(C2)x1*
Flexible PWB for
optical pickup

(A2)x2
ø1x2.5mm

Top Cabinet

Pull

(C2)x1

Bottom Cover

Figure 7-1

Pull

(C3)x3

Pull

Figure 7-2

(A2)x2
ø1x2.5mm

(A1)x1

Pull

(A2)x2
ø1x2.5mm

(B1)x2
ø1x2.5mm

(C1)x1
ø2x3mm

Main PWB

(B2)x1

Pull

Pull

Mechanism Unit

Figure 7-3

– 7 –

MD-S301MK

(A2)x3
ø1.4x2.8mm

MD Mechanism

Spindle Motor

Solder joint of mechanism
flexible PWB
(A1)x1

REMOVING AND REINSTALLING THE MAIN PARTS

Remove the mechanism according to the disassembling meth­ods 1 to 4. (See Page 7.)

How to remove the spindle motor (See Fig. 8-1.)

1. Remove the flexible PWB solder joint (A1) x 1.

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

* When installing the spindle motor, gently press in the arrow

direction (in view of grating).

How to remove the sled motor (See Fig. 8-2.)

1. Remove the stop washer (B1) x 1 pc., and remove the gear
(B2) x 1 pc.

2. Remove the screws (B3) x 2 pcs.

3. Remove the flex PWB soldering joint (B4) x 3 places, and
remove the sled motor.

Note:

Be careful so that the motor gear is not damaged.
(If the gear is damaged, abnormal sound is emitted when
searching is performed.)

Bracket

Sled Motor

Figure 8-1

(B3)x1
ø1.4x1.2mm

(B3)x1
ø1.4x1.5mm

Stop Washer
(B1)x1

(B2)x1

(B4)x3
Solder joint of mechanism
flexible PWB

How to reinstall the optical pickup unit
(See Fig. 8-3.)

1. Remove the screw (C1) x 1 pc.

2. Slowly raise the optical pickup.

Note:

Be careful so that the motor gear is not damaged.
(If the gear is damaged, abnormal sound is emitted when
searching is performed.)

Figure 8-2

(C1)x1
ø1.7x3mm

Optical Pickup

Shaft

Figure 8-3

– 8 –

MD-S301MK

ADJUSTMENT

Preparation for adjustment (use the low reflection disc on which music has been recorded)

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 Low reflection disc MMD-212 (TEAC TEST MD) 88GMMD-212

Test disc

How to enter the TEST MODE (In STANDBY state)

1

Holding down the PLAY MODE button of remote control unit, press the VOL button and button of main unit.

2

Charge control "ON"

3

Indication of microcomputer version for one second [ ]

: Microcomputer ROM version
: EEPROM version

4

All LCD lighting for 2 seconds

5

TEST MODE STOP "_TEST_"
* When the button is pressed while the indication 3 and 4 appears, the mode is changed to TEST MODE STOP state.
* If the button is pressed while indication 3 to 5 appears, the EEPROM rewrite-enable area is updated, and the mode is changed

to STAND-BY state.

How to leave the TEST MODE

1

In the TEST MODE STOP state, version indication state and full-lighting state press the button.

2

Initialization of normal mode setting.

(BASS setting, VOL setting, etc.)

3

EEPROM rewrite-enable area updating and adjustment error setting.

(all items are adjusted when power is turned on in the normal mode)

4

Change to standby state.

Parts No.

—

Preliminary automatic adjustment or EEPROM rewriting

1

Short-circuit TP435 and TP421.

2

Perform preliminary automatic adjustment or EEPROM rewriting.

3

Press the button to set the standby state.

4

Release short-circuiting of TP435 and TP421.

– 9 –