Sharp CD-C250X, CD-C260X Schematic

SHARP

SERVICE MANUA.L

No.

S8531 CDC250XK

Illustration:

CD-C250NCP-C2

CD-C260X/CP-C250

MODEL

l

Difference between

CD-C250X

Front

l

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

CD=C25,OX(bK) C D-C%OX( B K)

CP-C250(BK)

differs from

Panel.and

CD-C250X

CD-C260X

CD Cover but their functions are the same.

and

CD-C260X

only in the design of cassette lid,

tLlIIi!m

DIGITAL

AUDIO

*

CONTENTS

SPECIFICATIONS.. VOLTAGE SELECTION AC POWER SUPPLY CORD AND PLUG NAMES OF PARTS OPERATION DISASSEMBLY REMOVING AND REINSTALLING THE MAIN PARTS

ADJUSTMENT .................................................................................................................................................................

TROUBLESHOOTING (CD SECTION) ............................................................................................................................

FUNCTION TABLE OFIC................................................................................................................................................

LCD

SEGMENT.. ..............................................................................................................................................................

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

TYPES OF TRANSISTOR BLOCK DIAGRAM..

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

SCHEMATIC DIAGRAM /WIRING SIDE OF REPLACEMENT PARTS LIST / EXPLODED VIEW

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

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

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

MANUAL

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

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

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

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

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

P.W.BOARD

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

__.

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

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

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

Page

10 12

18

21 22 22 23 27 29

.

-‘-

2 2 2 3

5 6 8

*

SHARP CORPORATION

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

TO THE OPERATION MANUAL.

SPECIFICATIONS

0

General

,Power

source: Power consumption: Dimensions:

“Weight:

0

Amplifier section

Output power:

-Output

terminals:

I

0

Tuner section

Frequency range:

0

Cassette deck section

Frequencylresponse:

Motor: Signal/noise ratio:

Wow and flutter:

Bias and erasure system:

Tape speed:

Heads:

.r,

11

AC

Height; 280 mm (11-l/16”)

Depth: 340 mm

MPO; 36 W (18 W + 18 W)

O/l 2712201230-240 V, 50160

80

W

Width; 270 mm (1

5.6

kg (12.3

PMPO; 100 W (total) (10 % T.H.D.)

RMS;

20 W (10 % T.H.D.) Speakers; 8 ohms Headphones; (recommended; 32 ohms)

FM; 88 - 108 MHz AM; 531-l ,602

530 -

1,620kHz

50 - 14,000 Hz (Normal tape) 50 - 15,000 Hz DC motor with electronic governor x 1

55 dB (TAPE 1, playback)

50 dB

(TAPE 2, recording/playback)

0.15 % (WRMS)

AC

4.76

cmisec. (l-7/8

TAPE-l: Playback x TAPE-2: Record/playback x 1

Erase x 1

(13-706”)

Ibs.)

(10 W +

16-50

kHz (9kHz

(1

(CrOz

O-5/8”)

10 W)

ohms

OkHz

tape)

ips.)

1

span)

Hz

0

Compact disc player section

Type: Signal readout: Rotational speed:

Error correction:

Quantization:

Filter:

D/A

converter: Frequency response: Dynamic range: Wow and flutter:

0

Speaker section

Type:

Maximum input power:

Rated input power: Impedance: Dimensions:

Weight:

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

VOLTAGE SELECTION

The voltage selector is located on the AC voltage selector box. If adjustment is necessary, use a screwdriver in order to slide the selector to match to the correct voltage.

3-disc

multi-play compact disc player Non-contact, conductor laser pickup 200 - 500 rpm CLV, Approx.

CIRC

(Cross Interleave Solomon Code) 16 bit linear

8-times oversampling

l-bit

D/A

20 - 20,000

90 dB (1 Unmeasurable (less than 0.001% W.

2-way,

3/4”) woofer and 5 cm tweeter]

20

w

10

w

8

ohms

Width; 170 mm

Height; 280 mm (11-l/16”) Depth; 201 mm

2.3 kg (5.1

3-beam

converter

Hz

kHz)

bass-reflex

(6-3/4”)

Ibs.)/each

semi-

digital filter

p.eak)

[12

cm (4-

(2”)

(7-15/16”)

Reed-

QACCAOOOl AWOO

QACCEOOOl AWOO

92LCoRDA1387C

AC POWER SUPPLY CORD AND PLUG

92LCrZrRDTl699A

92LPLUG027

92LPLUG155A

-2-

W

Front

panel

1.

Disc Tray

2. Disc Skip Button

3. Open/Close Button: &

4.

CD Repeat Indicator:

5. CD Pause Indicator: II

6.

Disc Number Indicator

7. FM Stereo Mode Indicator

8.

Extra Bass Indicator: X-BASS

9. Random Indicator

10.

CD Play Indicator:

11.

Record Indicator

12.

Preset Channel Indicator

13.

FM Stereo Indicator:

14. Function/Track Number/CD Counter/

~,.

Band/Frequency/Volume Indicator

15.

Memory Indicator

16.

Power Switch

17.

Record Start Button:

18.

Stand-By Indicator

19.

Remote Control Sensor

20.

Extra Bass Button: X-BASS

21.

Disc Number Select Buttons

22.

Function Selector Buttons

23.

Volume Up/Down Buttons:

24.

Tuning

25.

Reset Button

26.

Track Down/Review/Preset Down Button:

27.

Stop Button:

28.

Play/Repeat Button:

29.

Track Up/Cue/Preset Up Button:

30.

Equalizer Mode Button

31.

Memory Button

32.

Headp~hones

33.

(TAPE 1) Cassette Compartment

34.

(TAPE 2) Cassette Compartment

Up/Down

w

Socket

c

)

co

0

Buttons:

WC

A/V

Ic+h+l

NAMES OF PARTS

Illustration:

45

1011

6171819

+rn+r

24

CD-C250X

6

12 13 14

25

26

272829.30

33 34

(2021

78

9

%

2223

31

15

32

~-

-3-

n

Rear panel

I.

AM Loop Aerial Socket

2.

FM 75 ohms Aerial Terminal

3. Span Selector Switch

4.

Speaker Terminals

5. AC Power Lead

6.

AC

Voltage

n

Speaker section

7.

Tweeter

8.

Woofer

9. Bass Reflex Duct

TO.

Speaker Wire

Selector

6

Left speaker

.

rrrrrrrrrrrrr rrrrrrrrrrrrr rrrffrrrrrrrr rrrrrrrrrrrrr

Right speaker

fzl

q

Remote control

1.

Remote Control Transmitter Window

0

CD control section

2.

Disc Number Select Buttons

3.

Track Down/Review Button: 44 I

4. Stop Button:

5.

Disc Skip Button

6.

Track Up/Cue Button: +

7.

Play/Repeat Button: )

8.

Random Button

9.

Clear Button

10.

Memory Button

11.

Pause Button:

0

Tuner control section

12. Preset Up/Down Buttons: v I

0

Tape control section

13.

(TAPE 1) Play Button:

14. (TAPE

15.

(TAPE 2) Stop Button:

16.

(TAPE 2) Rewind Button:

17.

(TAPE 2) Play Button:

18.

(TAPE 2) Fast Forward Button:

n

II

1)

Stop Button:

IH

c

)

H

n

t(

)

0

u

I44

2 3

4

‘5,

16-

5

6

7

/I7

-18 ‘19

A

'20 '21

H

19.

Balance Control Buttons

20.

Function Selector Buttons

21.

Equalizer Mode Buttons

22. Volume Up/Down Buttons: v

23.

Extra Bass Button: X-BASS

24.

Power

Button

ir\

2423 22

-4-

OPERATION MANUAL

n

Proper use of the remote control

Aim the remote control at the remote control sensor within

50”,

with no obstacles, and operate as shawn.

Notes concerning use:

0

Replace the battenes if control distance decreases or

operation becomes erratic.

0

Periodically clean the transmitter window on the remote

control and the sensor on the main unit with a soft cloth.

0

Exposing the sensor on the main unit to strong light can

interfere with operation. Change the lighting or the direction of the unit.

0

Keep the remote control away from moisture, excessive

heat, shock, and vibrations.

0

The remote control’s usable range is between 0.2 m

and 6 m (20’) away from the sensor.

(6”)

RESETTING THE

MICROCOMPUTER

Reset the microcomputer by performing the following

procedure for the cases shown below:

0

To erase all of the stored memory contents, or

0

If the display does not function properly, or

0

The unit does not operate properly.

1

Set the POWER switch to STAND-BY.

2

Dtsconnect

Press the RESET button for at least 5 seconds

3

H

AM/FM interval (span)

The International Telecommunication Union

lished that member countries should maintain either a

kHz

or a 9 of any AM station. The illustration shows the 9 zones (regions 1 and gion 2).

Before using the unit, set the SPAN SELECTOR switch (on the rear panel) to AM tuning interval (span) of your area.

the AC power lead from the AC socket.

(ITUJ

has estab-

kHz

interval between broadcasting frequencies

3),

and the 10

kHz

interval zone (re-

10

interval

0

Set the SPAN SELECTOR switch to

interval (50

AM interval (100

kHz

FM interval), and

kHz

FM Interval).

“5019”

“lOO/lO”

To change the tuning zone:

1

Disconnect the AC power lead

2

Press the RESET button on the front panel for at least

3

seconds.

3

Set the SPAN SELECTOR switch as desired.

4

Reconnect the AC power lead into an AC socket.

from’the

Note:

0

When the SPAN SELECTOR switch is switched, the

memorised stations will be cancelled.

-5-

for 9

kHz

for 10

AC socket

AM

kHz

A.

cD-gmi&6ox

s

DISASSEMBLY

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 cassette tape and compact disc out of the unit.

2. Be sure to remove the power supply plug from the wall outlet before starting to disassemble the unit.

3. Take off nylon bands or wire holders where they need be removed when disassembling the unit. After servicing the unit, be sure to rearrange the leads where they were before disassembling.

4. Take

suffcient

care on static electricity of integrated

circuits and other circuits when servicing.

m

STEP

12Top Cabinet

Side Panel

(LeftlRiqht)

CD Player

3

CD

Traym

Unit/

Cover

PROCEDURE

1

Screw......................

1.

Screw.. ....................

2.

Screw.. .................... (82) x2

1.

Turn on the power supply,

open the disc tray, take out

the disc tray, and close.

(Note

2. Hook

3.

4.

4

Back Board

5

Headphons PWB ) 1. Screw . (El) xl Front Panel

(Note 2)

Display

PWB/

Switch

PWBI

Sub PWB

1.

2.

I.

2. Socket ..................... (F2) xl

3.

4.

1.

2.

3. Screw.. .................... (G3) xl

1)

._.........._..........

Hook . (C2) x3

Socket . . . . . . . . . . . . . . .

Screw......................

Screw.. ....................

Flat Cable ...............

Socket.. ...................

Screw.. ....................

Socket.. ...................

Screw.. ....................

Tape Mechanism 1. Open the cassette holder

2.

Screw

9

Main

PWBI

Deck

PWBi

Tuner PWB (with

1 Screw

2.

.._._.__.___._.__.__..

Screw (J2) xl

3. Socket . . . . . . . . . . . . . . . . . (J3) xl

Headohons PWB‘

10

CD Servo PWB

11

12

Disc Tray

1.

Screw.. ....................

2. Socket .....................

1 Screw

2. Cover . . . .

1. Screw

___.._.....__._.___.__

.._..._...._.....

__._.__._,.,.,....,,..

(M2)

1.

Screw

.._..._._..._.____..__

.._.....

(Al) x4

(Bl)

(Cl) x2

(C3)

(Dl)

/DP)

(Fl)

(F3)

(F4) (Gl)

(G2) x9

(Hl)

(Jl ) x5

(Ki) (K2)

(Ll )

(L2) xl (Ml) x4

(Pl) x4

‘IGURE

6-l

x2

6-l

6-2

x2

6-l

x2

6-3

x3

6-3

x2 x2

xl

‘7-1

7-1

x6

7-2

xl

7-3

it3

xl 7-4

7-4

7-5

Illustration:

Disc Tray

Hook (

c2 )

x3

CD-C250X

03 xlOmm

CD Player Unit

Front Panel

Figure 6-2

CD

(Note 3)

15

Senser PWB

Mechanism

I.

Screw

___.._.._.,__.._._.... (Ql)

1. Screw ......................

2. Socket .....................

xl

(Rl) xl

(R2)

xl

7-5

Note 1: if the power supply cannot be turned on, f& turn the gear

by hand as shown in Figure 7-3 to open the disc tray.

Note 2: Withdraw upward straight the flat cable.

1

STEP 1REMOVAL

1

Speaker

/

PROCEDURE

1.

Net

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

2. Front Panel .............

3. Screw.. .................... (A3) x6

(Al)

(A2) xl

xl

1

FIGURE

7-6 7-7

Main

m

PWB

j

i

+uner

Figure 6-3

PWB

(F4)e

03X8mt77

Note 3: After removing the Flexible PWB for the optical pickup

from the connector wrap the conductive aluminum foil around the front end of Flexible PWB so as to protect the optical pickup from electrostatic damage.

Switch

I

PWB

Figure

Fynt Pane’

7-1

(Gl j

xl

Tape Mechanism

( M2 )

x2

P--.

CD Player

Turntable

Unit

(M2)x2

Figure 7-4

03

xl Omm

Figure 7-2

(Kl

03

)x1

xl Omm

CD Servo PWB

(Pl)x4

(

RI ) xl

03

xl

Omm

( Ql )

xl

02.6

xl0mmT 1

Care when installing the CD changer mechanism. Install the CD changer mechanism on the CD player base after

the shift lever has been set in the highest

Figure 7-5

03 xl 2mm

D

Mechanism

position.

hanger anism

. .

Figure 7-3

\

b

7-

Figure 7-6

03.5

xl4mm

( A2 ) xl

Figure 7-7

Speaker

REMOVING AND REINSTALLING THE MAIN PARTS

TAPE MECHANISM

Perform steps 1, 2, 3, 4, 6 and 8 of the disassembly method to remove the tape mechanism.

SECTION

How to remove the record/playback and erase

heads (TAPE 2) (See Fig. 8-l.)

1.

Carefully bend the record/playback head pawls (Al) x 2

in the direction of the arrow @, and remove the playback head upwards.

2. Carefully bend the three pawls direction

($9,

and remove the erase head upward.

(Bl)

x 3

PCS.,

in the arrow

How to remove the playback head (TAPE

PCS.,

record/

1)

(See Fig. 8-2.)

1.

Carefully bend the playback head pawls (Cl) x 2

direction of the arrow 0, and remove the playback head

upwards.

How to remove the pinch roller (TAPE

(See Fig.

1.

Carefully bend the pinch roller

arrow 0, and remove the pinch roller

Note:

When installing the pinch roller, pay attention to the spring mounting method.

S-3.)

paw1

in the direction of the

(Dl)

How to remove the belt (TAPE 1) (See Fig.

1.

Remove the main belt (El) x 1

PC.,

from the motor side.

PCS.,

in the

l/2)

x 1 upwards.

8-4.)

Pawl (

Bl

p%FE

JTAPEI]

Figure

8-1

Record/Playback

r--.,

Head

How to remove the belt (TAPE 2) (See Fig.

1. Remove the tape 1 main belt (El) x

2. Remove the tape 2 main belt

3. Remove the

FFiREW

belt (F2) x 1

(Fl)

Ipc.,

from the motor side.

x 1

PC.,

from the motor side.

pc.

8-4.)

How to remove the motor (See Fig. 8-5.)

1. Remove the belt.

2. Remove the screws bracket.

3. Remove the screws (G2) x 2

Note:

When mounting the motor, pay attention to the motor mounting angle.

(Gl)

02

x4mm

x2

(Gl) x

2

PCS.,

to remove the motor

PCS.,

to remove the motor.

Figure 8-2

Pinch Roller

Figure 8-3

(Dl)

xl

(G2) x2

02

x4mm

Figure 8-5

Figure 8-4

-8-

CD

MECHANISM SECTION

Perform steps 1, 2, 3, 10, 11, 12, and 13 of the disassembly method to remove the CD mechanism.

How to remove the loading motor (See Fig.

1.

Remove the drive belt (Al) x 1

2. Remove the screws (A2) x 2 motor.

PC.,

from the motor side.

PCS.,

to remove the loading

How to remove the select motor (See Fig.

1.

Removethescrews(Bl)x2pcs.,

toremovetheselectmotor.

9-1)

9-2)

(Al )x1

Drive Belt

Figure

9-1

(Bl)x2

02.6

x5mm

How to remove the pickup (See Fig. 9-3)

1. Removethe screws (Cl) x 2

x 1

pc.

2. Remove the stop washer (C3) x I

x 1 pc.

3. Remove the pickup.

Note:

After removing the Flexible PWB for the optical pickup from the

connector wrap the conductive aluminum foil around the front end of Flexible PWB so as to protect the optical pickup from electrostatic damage.

PCS.,

to remove the shaft (C2)

PC.,

to remove the gear (C4)

Figure

9-2

Figure 9-3

-9-

CD-E;5:0;6OX

MECHANISM

l

Driving Force Check

Torque Meter

Play:

TW-2412

l

Tot-clue

Check

Torque Meter

Plav: TW-2111

1

Fast forward: TW-2231

1

Rewind: TW-2231

l

Tape Speed

SECTION

Test Tape

I

Normal

speed

MTT-111

f

j

TAPE MECHANISM

Tape 1: Over 80 Tape 2: Over 80

Tape

30 to

60

g.

1 I

Adjusting

Point

Volume in motor.

ADJUSTMENT

Specified Value

9 g

Specified Value

1

cm

Specified Instrument

Value

3,000 i: 30 Hz

1

Tape 2

30to60

160to120gcm /60to120gcm

acm

Connection

Speaker terminal (Load resistance: 6 ohms)

TUNER SECTION

fL:

Low-range frequency

fH:

High-renge frequency

l

AM IF/RF

Signal generator: 400 Hz,

Test Stage / Frequency

IF

Band Coverage

1

Tracking

/

*l.

Input: Antenna,

*2.

Input: Antenna,

l

FMRF

Signal generator: 1

Test Stage Frequency Frequency

Band Coverage

RF

*l.

Input: Antenna,

*2.

Input: Antenna,

.-FM IF

Signal generator:

450

kHz

-

990

kHz

-

98.00 MHz 98.00 MHz (1

O-30 dB)

10.7

30%,

Frequency

1,602 1,620

531 530

990

Output: TP302 Output: TP301

kHz,

22.5

87.50

Output: Output: Speaker terminal

MHz, FM sweep generator

AM modulated

Display

kHz

or

kHz

or

kHz kHz

kHz

dev., FM modulated

Display

MHz

TP301

Adjusting

L303(fL): 185Vi:50 mV

L302

Setting/

Adjusting Connection

Parts

T351

(fL):

T304

1.1 IO.1

(fL):

T302

Serringl

Point

Instrument

*1

*2

v

*1

instrument

Connection

5

*1

l

2

/

TUNER

PWB (

l

FM Mute Level

Signal generator: 1

Frequency

98.00 MHz (25

dBbV)

*

Adjust so that an output signal appears.

IC301

1

FM

IFI

L302

kHz,

40

kHz

Frequency

Display Parts

98.00 MHz

FM ANTENNA

1

TERMINAL

AM ANTENNA TERMINAL

dev., FM modulated

Adjusting

1 VR35’*

Instrument

Connection

Figure 10-l ADJUSTMENT POINTS

l

Setting the test mode

Any one of 4 test modes can be set by pressing several keys as follows

<MEMORY> + <CD> +

TEST

l

MODE

TEST 4 mode

<POEER>

TEST : CD operation test

Function- CD test mode

Setting of TEST 4 mode

k&cation

of CD TST mode (All LCD lights)

ObEN/CLOSE operation is manual operation. T<e

pickup can be moved by using the

<MEMORY> When the tracking servo is - The pickup returns to the - When the tracking servo is - The pickup returns to the turned on, PLAY is started at once.

t

L

<PLAY> key input

Note:

TOC. IL is performed, and the ordinary PLAY is performed. - Press

-

If the following key is pressed during PLAY, it is possible to

specify directly any Track No.

<Disc

<Disc Number 2> key: Track 8

<Disc

(w)

or

(+) key.

<STOP> ordinary stop position.

Number l> key: Track 3 Number 3~ key: Track 15

Only in STOP state it is possible to slide the pickup with the

VOL. --- Last memory

BAC.--- CENTER R.GEQ.

--- FLAT

X-BASS --- OFF

*

Canceling method - POWER OFF

CD

SECTION

Since this CD system incorporates the following automatic adjustment function, when the pickup is replaced, it is not necessary to readjust it.

l

Automatic adjustment item

1

IL is not performed.

1

<MEMORY> turned off, PLAY is started

at once.

(m)

or

(4q)

<STOP>

ordinary stop position.

<STOP>

key. - Stop

key.

1.

Focus offset (Fig. 1

2. Tracking offset (Fig.

3. E/F balance (tracking error balance) (Fig. 11-3)

4. RF level AGC function (HF level: constant)

5. RF level automatic follow-up of the tracking gain

This automatic adjustment is performed each time a disc is changed. Therefore, each disc is played back using the optimal settings.

l-l)

11-2)

0.1s

0.50

tci @

200 1Vidi IC 1

ms

v

FD

TO

I I I

Figure 11-l

FOCUS

OFF-SET ADJUST

TRACKlNG

OFF-SET ADJUST

TRACKING/ ERROR BARANCE

‘.

IADJUST

1Oms

0.50 v ICl

1Oms

0.50 v ICI

II’ 1 I Ill1

II

@

FD

@

TO

I I

Enlaraed

“11””

TRACK!NG

OFF-SET ADJUST

Figure

11-2

TE

Figure 1 l-3

-ll-

/

CD SERVO

PWB /

Figure 11-4 CHECKING POINTS

TROUBLESHOOTING (CD SECTION)

When the CD does not function

When the CD section does not operate When the objective lens of the optical pickup is

objective

lens,and

check the playback

operation.When

this section does not operate even after the above step is takencheck the

following items.

Remove the cabinet and follow the troubleshooting instructions. “Track skipping and/or no TOC(Table Of Contents) may be caused by build up of dust other foreign matter on the laser pickup lens. Before attempting any adjustment make certain that the lens is clean. If not, clean it as mentioned

Turn the power off.

Gently clean the lens with a lens cleaning tissue and a small amount of isopropyl alcohol.

Do not touch the lens with the bare hand.

Is L

pulse (approx. 300 ms) input into the

turntable is rotating?

PC701

pin 26 when the

b

Check the SW2 and the wiring from the

No

sw2.

dirty,this

section may not

below.”

operate.Clean

IC701

pin 26 to the

the

,

Is there following voltage input on the

Yes

IC701

state?

When the CD mechanism is moved up:

In other states:

H

L

Yes

f

/

Check

Q901, Q902,

Is there following voltage input on the state?

-

When the CD mechanism is moved up:

In other states:

and Q904 and the periphery.

IC701

L

H

Yes

t

IS L

output from the

IC701

pin 25

I

Yes

pin 9 in the specific

, Check the SW3 and the wiring from the

No

sw3.

I

+

Check the SW3 and the wiring from the

No

sw3.

Check the wiring from the

IC701

pin 25 to the Q903 base.

I

IC701

pin 9 to the

.

PC701

pin 9 to the

Is H output from the

IC701

pin 19 during SEC when the disc skip

switch is pressed?

Yes

v

Is 4v

output

from

the

Q901

above?

emitter during operation stated

Yes

t

Check turntable motor (Ml) and turntable mechanism.

1.

-12-

Check the wiring of

Check

Q901,

IC701

Q902,

Q904 and the periphery.

pin 19 and Q904 pin 2.

OK

IC701

defective.

Is there following voltage input in specific stateofIC701

Open state:

Close state: OV

Intermediate state between open state and close state:

2.5V

Yes

+

Is H output to CLOSE key is

IC701

pin 70 or 71 for 5 seconds when the OPEN/

pressed?105

is defective. Replace it.

Yes

5V

8’7

Check the

Check the wiring of the and 9.

SW1

and the wiring from the

IC701

lC701

pins 70 and

defective.

OK

IC701

71, IC901

pin 8 to the

pins 1

SWl.

Is 4V output between

above?

/

The CD operating keys don’t work.

Check the CD, DPS microcomputer, power supply, 4.19 MHz and

16.93 MHz clock, and reset terminal.

Check the waveform of SCK, SO (DATA) and SI (COMM). (Fig.

14-l-5)

See if the pick-up is in the pick-up in SW4 position.

IC901

pins 3 and 7 during operation stated

Yes

i

Yes

Check the periphery of

IC901.

I

Yes

If the items mentioned above are OK, check the main microcomputer

IC701.

-13-

COMM

DATA

Figure

6 BYTE

1

6 BYTE

1

6 BYTE

100 ms interval

14-1

CD microcomputer -- Main microcomputer data transmission

1

GNP

7

5 Pin 20ms

2.00

v

COMM

6

20ms

2.00

v

DATA

7 Pin 20ms

2.oov i

SCK

COMM

I

DATA

Figure

8

BIT

8

BIT

14-2

CD microcomputer --

CK: 262

((

I

8 BIT

8

BIT

kHz

DATA and COMM are read at rise of SCK.

LSB FIRST

Main microcomputer data transmission

CNP 7

5

t ; Iilr

5ms

2.00

v

COM

6 Pin 5 ms

2.00

v

DATA

7 Pin

5 ms

2.00

v

SCK

or less

GNP

7

5 Pin

5~~2.00 V

COM

6 Pin

5lJS

2.00

v

DATA

7 Pin

5lJS

2.00

v

SCK

Figure 14-3

Figure

14-5

-

14-

Figure

14-4

Check the Focus - HF svstem.

1

Playback can be performed without a disc.

Yes

I-

No

I

Focus search OK

Does the output waveform of ICi(lG)(FD) match that shown in Fig.

15-i?

1

No

i

Check the

Check the microcomputer data on pins

(53)CE.

Does the DRF signal change fr

IC1(50)(CLK)

line,

4MHz.

(51)(CL), (52)(DAT)

Yes

and

No

Check the area around IC5CNP2.

0.5s

0.50 v Cl @ FD

0%

0.50 v ICl

@TD

Check the laser diode driver. Check the area around

If the disc is not turning, the DRF

should not change to

ICl(l6) -

“H”.

Focus search is performed two times when play operation is

done without

disc.

Figure 15-l

(21) (focus servo circuit).

Check the spin system.

Is HF waveform normal (see th

i

Check the tracking system.

HF

O.lV/DIV O.Susec/DIV(DC)

(When playing

back the disc)

Figure 15-2

-* ,

*~

4

Yes

0.5s

1 .oo v

ICl @

0.5s

-15-

Check the periphery-of

ICl pins 41 and 42.

Waveform is unstable. Check the spin system.

Waveform in case of normal

FD

Figure

15-3

play-back

Check waveform of ICl pin 7 (TE).

--+

The waveform shown in Fig.16

appears, and no-disc state apperas soon.

Check the periphery of IC 1

;i;n6;o

Although IL is possible, play is impossible.

I

Yes

pin 15, and IC 5 to

Data cannot be read.

5ms

1.00

v

ICI

@TE

5 ms

5.0

v

ICI @j)

DRF

Figure 16

program top cannot

I

Check the VCO-PLL system.

be reached.

Check the periphery of

I

Play operation is performed without disc.

1

Yes

+

The turntable rotates a little.

The turntable fails to rotate or rotates at

high speed.

- 16-

The spin driver circuit is normal.

Check the periphery of ICl pins 23 to 27, pin 39, and pin 40, pin 13 and pin 14,

IC5

to

CNPS.

IC2

l

Checking

Play operation is performed when disc exits.

tke

VCO-PLL system

Yes

1

Although HF waveform is normal,

0.5s

1 .oo v

IC2 @

PDO

0.5s

1

.oo v

ICI @ FD

Figure 17-l

l

Although MF waveform is norm& ‘and the

indication

Check IC 2

is,normat, no.srrund

is

emRted.

&me

Stop

-->

Play

As VCO freque-

ncy is locked at

4.32 M Hz, voltage of PDO

rises and stabili-

zes.

Check PDO waveform (Fig.

Error

Check the

Usually, the number of pulses of flawless disc is 100 pulsesisec

ICl

pins 43 and 44,

17-1).

IC2

pins

3,5,7,

10, and

11.

1

Check

IC2

pins 48, 49, 52, and 53 (Fig.

Check the periphery of

IC3

(OPAMP).

Yes

17-2,3).

0.2ps

2.00

v

RCHNiLCHN

0.2fJs

2.00

v

RCHPILCHP

0.2us

2.00

v

RCHN/LCHN

Figure

17-2

In STOP state

CHP/CHN

clocks are the same. and output is not given.

-~

Due to difference in waveform of

CHP/CHN

(duty ratio) in PLAY mode output is given.

-17-

Figure 17-3

Sharp CD-C250X, CD-C260X Schematic

Specifications and Main Features

Frequently Asked Questions

User Manual