Sony DEJ-785 Service manual

D-EJ785

SERVICE MANUAL

Ver 1.0 2002.12

SPECIFICATIONS

Canadian Model

AEP Model

UK Model

E Model

Austr alian Model

Chinese Model

Tourist Model

Model Name Using Similar Mechanism NEW CD Mechanism Type CDM-3325ER

Optical Pick-up Name DAX-25E

System

Compact disc digital audio system

Laser diode properties

Material: GaAlAs Wavelength: λ = 780 nm Emission duration: Continuous Laser output: Less than 44.6 µW (This output is the value measured at a distance of 200 mm from the objective lens surface on the optical pick-up block with 7 mm aperture.)

Power requirements

For the area code of the model you purchased, check the upper left side of the bar code on the package.

•Sony NH-WM2AA rechargeable batteries: 2.4 V DC

•Two LR6 (size AA) batteries: 3 V DC

•AC power adaptor (DC IN 4.5 V jack): Canadian and Taiwan models: 120 V, 60 Hz UK model: 230 V, 50 Hz Australian model: 240 V, 50 Hz AEP, East European, E, Korean and Tourist models: 100 - 240 V, 50/60 Hz Hong Kong model: 230 V, 50/60 Hz Chinese model: 220 V, 50 Hz

Battery life* (approx. hours)

(When the CD player is used on a flat and stable place.) Playing time varies depending on how the CD player is used.

G-PROTECTION on off

Two NH-7WMAA 15 10 (charged for about 2 hours**)

NH-WM2AA 32 24 (charged for about 4 hours**)

Two Sony alkaline 50 35 batteries LR6 (SG) (produced in Japan)

*Measured value by the standard of JEITA (Japan

Electronics and Information Technology Industries Association).

** Charging time varies depending on how the

rechargeable battery is used.

Dimensions (w/h/d) (without projecting parts and controls)

Approx. 136.0 × 19.6 × 136.0 mm (5 3⁄

Mass (excluding accessories)

Approx. 155 g (5.5 oz)

Operating temperature

5°C - 35°C (41°F - 95°F)

Supplied accessories

AC power adaptor (1) Headphones/earphones with remote control (1) Rechargeable batteries (2) Battery carrying case (1)

Design and specifications are subject to change without notice.

× 25⁄32 × 5 3⁄8 in.)

9-874-272-01 Sony Corporation

2002L0500-1 Personal Audio Company C 2002.12 Published by Sony Engineering Corporation

PORTABLE CD PLAYER

D-EJ785

1. SERVICING NOTES............................................... 3

2. GENERAL ................................................................... 6

3. DISASSEMBLY

3-1. Disassembly Flow........................................................... 7

3-2. Spring (A)/(B) ................................................................. 7

3-3. Lid (Upper) Sub Assy ..................................................... 8

3-4. Cabinet (Front) Block ..................................................... 8

3-5. Optical Pick-up Section (CDM-3325ER),

MAIN Board ................................................................... 9

4. ELECTRICAL CHECK .......................................... 10

5. DIAGRAMS

5-1. Block Diagram – MAIN Section –................................ 11

5-2. Block Diagram

– AUDIO/PO WER SUPPLY Section – .......................... 12

5-3. Note for Printed Wiring Boards and

Schematic Diagrams ....................................................... 13

5-4. Printed W iring Board

– MAIN Board (Component Side) – .............................. 14

5-5. Printed W iring Board

– MAIN Board (Conductor Side) – ................................ 15

5-6. Schematic Diagram – MAIN Board (1/3) –.................. 16

5-7. Schematic Diagram – MAIN Board (2/3) –.................. 17

5-8. Schematic Diagram – MAIN Board (3/3) –.................. 18

5-9. IC Pin Function Description ........................................... 21

On AC power adaptor

• Use only the AC power adaptor supplied. Do not use any other AC power adaptor. It may cause a malfunction.

Polarity of the plug

Notes on chip component replacement

•Never reuse a disconnected chip component.

• Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.

Flexible Circuit Board Repairing

•Keep the temperature of the soldering iron around 270 ˚C dur-

ing repairing.

• Do not touch the soldering iron on the same conductor of the

circuit board (within 3 times).

• Be careful not to apply force on the conductor when soldering

or unsoldering.

CAUTION

Use of controls or adjustments or performance of procedures other than those specified herein may result in hazardous radiation exposure.

6. EXPLODED VIEWS

6-1. Front Cabinet Section ..................................................... 26

6-2. Rear Cabinet Section ...................................................... 27

6-3. Optical Pick-up Section (CDM-3325ER)....................... 28

7. ELECTRICAL PARTS LIST ............................... 29

SAFETY-RELATED COMPONENT WARNING!!

COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH MARK 0 ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANU AL OR IN SUPPLEMENTS PUBLISHED BY SONY.

ATTENTION AU COMPOSANT AYANT RAPPORT

LES COMPOSANTS IDENTIFIÉS P AR UNE MARQUE 0 SUR LES DIAGRAMMES SCHÉMATIQUES ET LA LISTE DES PIÈCES SONT CRITIQUES POUR LA SÉCURITÉ DE FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS QUE PAR DES PIÈCES SONY DONT LES NUMÉROS SONT DONNÉS DANS CE MANUEL OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.

À LA SÉCURITÉ!

SECTION 1

SERVICING NOTES

D-EJ785

ABOUT CD-Rs/CD-RWs

• This CD player can play CD-Rs/CD-RWs recorded in the Compact Disc Digital Audio (Audio CD) format, b ut playback capability may vary depending on the quality of the disc and the condition of the recording device.

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT

The laser diode in the optical pick-up block may suffer electrostatic breakdown because of the potential difference generated by the charged electrostatic load, etc. on clothing and the human body . During repair, pay attention to electrostatic breakdown and also use the procedure in the printed matter which is included in the repair parts. The flexible board is easily damaged and should be handled with care.

NOTES ON LASER DIODE EMISSION CHECK

The laser beam on this model is concentrated so as to be focused on the disc reflective surface by the objective lens in the optical pick-up block. Therefore, when checking the laser diode emission, observe from more than 30 cm away from the objecti ve lens.

BEFORE REPLACING THE OPTICAL PICK-UP BLOCK

Please be sure to check thoroughly the parameters as par the “Optical Pick-Up Block Checking Procedures” (Part No.: 9-960-027-

11) issued separately before replacing the optical pick-up block.

Note and specifications required to check are given below.

LASER DIODE AND FOCUS SEARCH OPERATION CHECK

During normal operation of the equipment, emission of the laser diode is prohibited unless the upper lid is closed while turning ON the S801. (push switch type) The following checking method for the laser diode is operable.

• Method: Emission of the laser diode is visually checked.

1. Open the upper lid.

2. With a disc not set, turn on the S801 with a screwdri ver having

a thin tip as shown in Fig.1.

3. Press the

4. Observing the objective lens, check that the laser diode emits

light. When the laser diode does not emit light, automatic power control circuit or optical pickup is faulty. In this operation, the objective lens will move up and down 5 times along with inward motion for the focus search.

B X key.

detection lever

• FOK output: IC601 yg pin When checking FOK, remove the lead wire to disc motor.

• RF signal P-to-P value: 0.45 to 0.65 Vp-p

detection lever

S801

MAIN board

Fig. 1 Method to push the S801

D-EJ785

SERVICE MODE

In the Service mode, this set can check the following.

Note: Use RM-MC10L (Part No. 1-476-211-

mode. (Use dot matrix Remote Commander)

1. Service Mode Setting Method

To set the service mode, perform as follows.

1) Make sure that the power is not turned on.

2) Check for the following states:

CD lid open detection switch (S801) .... OFF

Solder bridge at TAP802 (OPEN) ......... OPEN

[][]

), when you operate service

[HOLD] switch (S803) .......................... OFF

[AVLS] switch (S808) ........................... OFF

[G-PROTECTION] switch (S802) ........ ON

3) Short the solder bridge at the TAP801 (TEST) on the MAIN board (see Fig. 2).

4) Turn the power on, and then set a CD.

– MAIN Board (Component Side) –

TAP801

(TEST)

TAP802 (OPEN)

3. Operation of Keys and Knobs in Service Mode

The following operation can be checked by operating the buttons on the set and remote commander.

• B X key on the set or X key on the remote commander Focus and tracking/sled servo off Spindle servo on

Remote Commander LCD display

0000

Note: Do not look directly at the laser beam from the optical pick-up.

(play mode)

[HOLD] switch is on:

Auto adjustment value a becomes as follows each time the key is pressed.

1) [TRK:MIN:SEC] = RF:FE:TE DC offset adjustment value

2) [TRK:MIN:SEC] = EF: :EF balance adjusted value

3) [TRK:MIN:SEC] = Ga:FG:TG gain adjusted value

[AVLS] switch is on:

Press CHARGE x and B X keys on the set or x and X keys on the remote commander simultaneously, and RF gain changes to 0 dB (for normal CD) and +12 dB (for CD-RW).

• . / > keys on the set or B > / . knobs on the remote commander Tracking servo off Optical pick-up movement (outward or inward)

Note: Do not move forcibly the optical pick-up exceeding the most-out-

side or most-inside track.

• CHARGE x key on the set or x key on the remote commander All servos (focus/tracking/sled) off

• [RPT/ENT] key on the remote commander Tracking gain up mode

Fig. 2

2. Operation in Service Mode

When the Service mode is set, the LCD on the remote commander displays the microcomputer version display.

Remote commander LCD display

Microcomputer version display

All lit

Service mode

VA020

888

DDDD

BASS12

Remote Commander LCD display

Up0000

(For the rest, turn the power off and then turn it on again)

[PLAYMODE] key on the remote commander

•

[HOLD] switch is off:

Spindle speed becomes 1.65/2.0/2.65/3.5 times each time the key is pressed Tracking/spindle servo on

Remote Commander LCD display

010001

040004

(For the rest, turn the power off and then turn it on again)

• [SOUND] key on the remote commander Servo gain adjustment Tracking servo off

• [DISPLAY] key on the remote commander On/off switching of the DOUT LED (AEP, UK and East European models) and error rate display

• [VOL +] / [VOL --] keys on the set or remote commander 2-step volume setting

(1.65 times)

(3.5 times)

4. Service Mode Releasing Method

To release the service mode, perform as follows.

1) Turn the power off.

2) Open the solder bridge at the TAP801 (TEST) on the MAIN board.

Note: Remove the solder completely.

5.Error Rate Check Display

The C1 error rate check display mode becomes active if the following operation is performed during the operation in the service mode.

1) Turn the power off, and cancel other service operations.

2) Turn the power on, and then set a CD and play it with the X key on the remote commander.

Remote Commander LCD display

0000

3) Press the [SOUND] button on the remote commander to make automatic adjustment.

4) Press the [PLAYMODE] button on the remote commander.

D-EJ785

Remote Commander LCD display

010001

5) Press the [DISPLAY] key on the remote commander, and the C1 error rate display will be activated and the LCD on the remote commander will display as follows.

Remote Commander LCD display

Er****

Note: In the play state, press the [SOUND] key on the remote commander

before pressing the [PLAYMODE] key. Wrong order of button operations will result in very large Er**** value.

6) Turn the power off.

7) Open the solder bridges at the TAP801 (TEST) on the MAIN board.

Note: Remove the solder completely.

**** value 0000 to 0099 : OK more than 0100 : NG

D-EJ785

CD player (front)

12 Jog lever (u (play/

pause)•./> (AMS/ search))

3 CHARGE/x •

CHARGE lamp

4 VOL +*/–

SECTION 2

GENERAL

This section is extracted from instruction manual.

Strap holes

OPEN

i (headphones) jack

5 HOLD

*The button has a tactile dot. **AEP, UK and East European models only

CD player (inside)

6 AVLS

7 G-PROTECTION

Remote control

Display

4 VOL +/–

12 Jog lever (u

Open the battery compartment lid.

(play/pause)•ENT (enter) • ./> (AMS/search))

DC IN 4.5 V (external power input) jack

LINE OUT/LINE OUT (OPTICAL)** jack

Insert the # end first (for both batteries).

Display on the remote control

AV LS

Playing time

Track number

Play mode

Clip

5 HOLD

8 DISPLAY

Note

Use only the supplied remote control. You cannot operate this CD player with the remote control supplied with other CD players.

9 SOUND

q; P MODE/

Remaining battery power

Sound mode

• This set can be disassembled in the order shown below.

)

3-1. DISASSEMBLY FLOW

D-EJ785

SECTION 3

DISASSEMBLY

SET

3-2. SPRING (A)/(B)

(Page 7)

3-3. LID (UPPER) SUB ASSY

(Page 8)

3-4. CABINET (FRONT) BLOCK

(Page 8)

3-5. OPTICAL PICK-UP SECTION (CDM-3325ER),

MAIN BOARD (Page 9)

Note: Follow the disassembly procedure in the numerical order given.

3-2. SPRING (A)/(B)

spring (B

spring (A)

D-EJ785

3-3. LID (UPPER) SUB ASSY

lid upper sub assy

3-4. CABINET (FRONT) BLOCK

Open the lid battery case.

lid upper sub assy

boss

cabinet front sub assy

boss

eight screws (B2)

cabinet (front) section

claw

knob (AVLS)

knob (G-PRO)

Note : On installation of cabinet (front) assy,

adjust the position of switch (S802) and knob (G-PRO), switch (S808) and knob (AVLS).

S802

S808

claw

3-5. OPTICAL PICK-UP SECTION (CDM-3325ER), MAIN BOARD

main board

spacer

flexible board (CN501)

insulator

optical pick-up section (CDM-3325ER)

screw (B) (1.4)

Hold up both the main board and the optical pick-up section at once, and remove them form the cabinet (lower) sub assy.

Note : Handle the flexible board with care when

you hold up the optical pick-up section.

Note : On installation of main board,

adjust the position of switch (S803) and knob (hold).

insulator

two connectors (CN502, 503)

terminal board (relay), battery

knob (hold)

S803

D-EJ785

SECTION 4

ELECTRICAL CHECK

The CD section adjustments are done automatically in this set. In case of operation check, confirm that focus bias.

PRECAUTIONS FOR CHECK

1. Perform adjustment in the order given.

2. Use YEDS-18 disc (P art No.: 3-702-101-01) unless otherwise indicated.

3. Power supply voltage requirement: DC4.5 V in DC IN jack.

(J401)

VOLUME : Minimum

[AVLS] switch : NORM [HOLD] switch : OFF [G-PROTECTION] switch : ON

FOCUS BIAS CHECK

Condition:

• Hold the set in horizontal state.

Connection:

MAIN board

TP630 (RF) TP421 (MAINGND)

2 k

Ω

oscilloscope

(AC range)

+ –

Procedure:

1. Connect the oscilloscope to the test points TP630 (RF) and TP421 (MAINGND) on the MAIN board.

2. Set a disc. (YEDS-18)

3. Press the B X key on the set.

4. Check the oscilloscope waveform is as shown below. A good eye pattern means that the diamond shape (◊) in the center of the waveform can be clearly distinguished.

RF Signal reference Waveform (Eye Pattern)

VOLT/DIV : 100 mV (With the 10:1 probe in use) TIME/DIV : 500 ns

RF level

0.45 to 0.65 Vp-

To watch the eye pattern, set the oscilloscope to AC range and increase the vertical sensitivity of the oscilloscope for easy watching.

5. Stop revolving of the disc motor by pressing the CHARGE x key on the set.

Connecting and Checking Location:

– MAIN Board (Conducter Side) –

TP630

(RF)

TP421

(MAINGND)

5-1. BLOCK DIAGRAM – MAIN Section –

DETECTOR

(Page 12)

OPTICAL PICK-UP BLOCK

LASER DIODE

(FOCUS)

2-AXIS DEVICE

(TRACKING)

M902

(SPINDLE)

VCC

DAX-25E

OPSTB

OPGSW

VCC2

M901

(SLED)

COM

U OUT

V OUT

W OUT

PREDRIVER

SECTION 5

DIAGRAMS

FOCUS/TRACKING COIL DRIVER SLED/SPINDLE MOTOR DRIVER

IC401 (1/2)

FO1

RO1

FO2

48 46

44 42

RO2

H BRIDGE DRIVER

FO3 RO3

CONTROLLER,

CONTROL

CIRCUIT

RI1

RI2

RI3

D-EJ785

RF AMP,

DIGITAL SIGNAL PROCESSOR,

DIGITAL SERVO PROCESSOR,

D-RAM CONTROLLER

IC601

RFDC

RFAC

FI1

56 55

FI2

58 57

FI3

60 59

SYNC

CPU

INTERFACE

PWM

BRK

DATA

CLOCK

LATCH

WAKEUP

39 38 40

BUFFER

IC403

100

96 95

98 97

104 103 102

SFDR SRDR

FFDR FRDR

TFDR TRDR

C176 MDP MDS

FG/FGSEL

XPOWLT

HG XSTB

HG GUP

XWAKE

SCOR

WDCK

WFCK

MDS

XTAO

XTAI

RFAC

XSOE SENS R4M XLAT CLOK SCOR SDTO

RFDC

SFDR

SRDR

FFDR FRDR TFDR

TRDR

SIGNAL

PROCESSOR

MDP

F B A

SDTD

SENS

161415181711

MSDTO

SYSTEM CONTROLLER

IC801 (1/2)

BLOCK

CLOCK

MSDTI

XLAT

MSCK

SYSM

AMUTE

DOUT

D0-D3

4, 3, 6, 5

A0-A9

116 – 113, 17 – 15, 13 – 11

XRAS

XWE

XCAS

XTAI

XTAO

AOUT1

AOUT2

HPL

HPR

LRMU

XRST

1, 2, 24, 25

9 – 12, 14 – 18, 5

XRAS

XWE

XCAS

X601

16.9344MHz

D1 – D4A0 – A9

D-RAM

IC603

DIGITAL

OUT

MEMORY

CONTROLLER,

BUS BOOST

BLOCK

LPF

SERVO BLOCK

XSOE

R4M

242232232021

XIN

XLAT

XSOE

FOK

AEP, UK, Eeast European models

DOUT

AOUTL, AOUTR

(Page 12)

HPL, HPR

(Page 12)

LRMU

(Page 12)

• SIGNAL PATH

: CD PLAY (ANALOG OUT)

: CD PLAY (OPTICAL OUT)

XRST

RESET

RSTOUT

RESET

WAKEUP

SWITCH

Q402

S803

HOLD

OFF

HOLD

VCPU B+

S801

CD LID OPEN

()

DETECT

VCPU B+

1111

+ 23 hidden pages

Sony DEJ-785 Service manual

TABLE OF CONTENTS

SERVICING NOTES

GENERAL

3-1. DISASSEMBLY FLOW

DISASSEMBLY

3-2. SPRING (A)/(B)

3-3. LID (UPPER) SUB ASSY

3-4. CABINET (FRONT) BLOCK

3-5. OPTICAL PICK-UP SECTION (CDM-3325ER), MAIN BOARD

ELECTRICAL CHECK

5-1. BLOCK DIAGRAM – MAIN Section –

DIAGRAMS