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[CONTENTS]


SECTION 1. SUMMARY

· SERVICING PRECAUTIONS .......................................................................................................... 1-2 · ESD PRECAUTIONS....................................................................................................................... 1-3 · SPECIFICATIONS ........................................................................................................................... 1-4


SECTION 2. ELECTRICAL

· ELECTRICAL TROUBLESHOOTING GUIDE ................................................................................. 2-1 · WAVEFORMS OF MAJOR CHECK POINT .................................................................................... 2-6 · INTERNAL BLOCK DIAGRAM of ICs .............................................................................................. 2-7 · BLOCK DIAGRAM ......................................................................................................................... 2-19 · SCHEMATIC DIAGRAM ................................................................................................................ 2-21 · PRINTED CIRCUIT DIAGRAM ...................................................................................................... 2-27


SECTION 3. CABINET MAIN CHASSIS & MECHANISM

· EXPLODED VIEW ........................................................................................................................... 3-1


SECTION 4. REPLACEMENT PARTS LIST.................................................................... 4-1

- 1-1 -

SECTION 1. SUMMARY
SERVICING PRECAUTIONS
Always disconnect the power source before:
1) Removing or reinstalling any component, circuit board, module or any other instrument assembly. 2) Disconnecting or reconnecting any instrument electrical plug or other electrical connection. 3) Connecting a test substitute in parallel with an electrolytic capacitor in the instrument. CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.

Do not defeat any plug/socket B+ voltage interlocks with which instruments covered by this service
manual might be equipped.

Do not apply power to this instrument and or any of its electrical assemblies unless all solid-state
device heat sinks are correctly installed.

Always connect a test instrument's ground lead to the instrument chassis ground before
connecting the test instrument positive lead. Always remove the test instrument ground lead last. 1) The service precautions are indicated or printed on the cabinet, chassis or components. When servicing, follow the printed or indicated service precautions and service materials. 2) The Components used in the unit have a specified conflammability and dielectric strength. When replacing any components, use components which have the same ratings. Components marked in the circuit diagram are important for safety or for the characteristics of the unit. Always replace with the exact components. 3) An insulation tube or tape is sometimes used and some components are raised above the printed writing board for safety. The internal wiring is sometimes clamped to prevent contact with heating components. Install them as they were. 4) After servicing always check that the removed screws, components and wiring have been installed correctly and that the portion around the service part has not been damaged. Further check the insulation between the blades of attachment plug and accessible conductive parts.

- 1-2 -

ESD PRECAUTIONS
[Electrostatically Sensitive Devices (ESD)]
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such omponents commonly are called Electrostatically Sensitive Devices (ESD). Examples of typical ESD devices are integrated circuits and some field-effect transistors and semiconductor chip components. The following techniques should be used to help reduce the incidence of component damage caused by static electricity. 1) Immediately before handling any semiconductor component or semiconductor-equipped assembly, drain off any electrostatic charge on your body by touching a known earth ground. Alternatively, obtain and wear a commercially available discharging wrist strap device, which should be removed for potential shock reasons prior to applying power to the unit under test. 2) After removing an electrical assembly equipped with ESD devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly. 3) Use only a grounded-tip soldering iron to solder or unsolder ESD devices. 4) Use only an anti-static solder removal device. Some solder removal devices not classified as "anti-static" can generate electrical charges sufficient to damage ESD devices. 5) Do not use freon-propelled chemicals. These can generate electrical charges sufficient to damage ESD devices. 6) Do not remove a replacement ESD device from its protective package until immediately before you are ready to install it. (Most replacement ESD devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material). 7) Immediately before removing the protective material from the leads of a replacement ESD device, touch the protective material to the chassis or circuit assembly into which the device will be installed. CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions. 8) Minimize bodily motions when handling unpackaged replacement ESD devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ESD device).

[CAUTION. GRAPHIC SYMBOLS]
THE LIGHTNING FLASH WITH APROWHEAD SYMBOL. WITHIN AN EQUILATERAL TRIANGLE, IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF UNINSULATED "DANGEROUS VOLTAGE" THAT MAY BE OF SUFFICIENT MAGNITUDE TO CONSTITUTE A RISK OF ELECTRIC SHOCK. THE EXCLAMATION POINT WITHIN AN EQUILATERAL TRIANGLE IS INTENDED TO ALERT THE SERVICE PERSONNEL TO THE PRESENCE OF IMPORTANT SAFETY INFORMATION IN SERVICE LITERATURE.

- 1-3 -

SPECIFICATIONS
1. GENERAL Power requirements ..................................................................................................................... DC12V~15V Ground system ................................................................................................................................... Negative Dimensions(W x H x D) ...................................................................................................... 188 x 58 x 166mm Weight .............................................................................................................................................. Net: 1.3kg 2. RADIO SECTION Frequency range Intermediate frequency Usable sensitivity Signal to noise ratio 3. COMPACT DISC SECTION Frequency response ..................................................................................................................... 40Hz~20kHz Channel separation ...................................................................................................................... 50dB(1kHz) Signal to noise ratio .................................................................................................................................. 60dB 4. AUDIO SECTION Maximum output power ....................................................................................................................... 50W x 4 Speaker impedance ............................................................................................................... 4 x 4 or 8 x 4 NOTE: The design and specifications are subject to change without notice in the sourse of product improvement. FM 65.0~74.0MHz(Optional), 87.5~108MHz 10.8MHz 10dBµV 55dB AM(MW) 522~1,620kHz (Optional:530~1,710kHz/ 520~1,620kHz) 450kHz 28dBµV 45dB

- 1-4 -

SECTION 2. ELECTRICAL
ELECTRICAL TROUBLESHOOTING GUIDE
(1) No Power.
Any Key power on. YES NO Is power turnd on? YES NO DISC loading? YES NO Check laser circuitry. Q501, IC502 Check focusing circuitry. Q501,IC501. Check DISC.
Check loading supply circuitry. Check power supply circuitry.

Q380, Q381, Q382,Q230 IC201 Pin1, IC401 Pin3.

Q350,Q351,Q353, PN505, IC401 Pin1

Does initial reading occur?

YES

Can disc be played? YES

NO

Check tracking servo circuitry. Q501,IC502, IC501.

Is audio output supplied? YES

NO

Check audio circuitry. IC501,IC601,IC803.

OK

- 2-1 -

(2) LCD light abnornal.
Any Key power on. (without DISC)

NO Do display LCD then light?

Check voltage in the power supply circuitry.

NO

Power supply circuitry defective. Q371,Q372,IC403

YES
Is u-com IC401 reset circuit normal? Pin88

NO

· Reset circuit defective. IC201 Surrounding circuit defective. · IC401 pin89 defective.

YES

Is u-com IC401X1, X2 terminal Pin38,39,41,42 input? OSC : 12.5MHz OSC : 32.768kHz

NO

X401, X422, C412, C413, C415, C416.

YES NO
Q260, PN401 front PCB pattern defective.

Is u-com IC401 keyin Pin9, 37, 51, 52, 64 5volt input?

YES
Is u-com IC401 Pin 66,67,87 output waveform normal?

NO

IC401, Pin66, 67, 87 front PCB pattern defective.

YES
Is IC901 Com1, Com2, Com3 output waveform normal?

NO

IC901, Surrounding circuit PCB pattern defective.

YES

Display LCD connector defective.

- 2-2 -

(3) Initial reading is not carried out.
Slide motor moves (With disc) YES

NO

Check the Voltage change of CN503 Pin10(6.4~6.8V) YES Check the Voltage IC501 Pin31 (1.4V~1.8V) YES Check the Data transmission from CN503(18,20,21) to CD DSP WAVEFORM #5 YES

NO

Defective connector CN503 Defective IC501

NO

NO

Spindle motor turns WAVEFORM #1 YES (with disc)

NO

Defective connector CN503 Defective MICOM

Does RF waveform appear? IC502 Pin8 WAVEFORM #2

NO

Check the Data transmission from CN503 Pin19 to MICOM WAVEFORM #5 YES Check the TRVP Voltage IC501 Pin31 YES
1.4~1.8V

NO

Defective connector CN503 Defective IC504

NO Defective IC501

YES

Check the change of SL +, SL - Voltage IC504 Pin13,14

3~4V

NO

Defective IC504

YES Laser light check A ? Defective contact CN502 Defective PICK-UP

Does FA+ waveform appear at IC501 Pin31? WAVEFORM #3 focus coil drive wareform. YES Does TE waveform appear at IC502 Pin21? WAVEFORM #4 TRACKING ERROR wareform YES Is rotation normal?

NO

NO

NO YES Is there no dropout of RF signal? YES Defective IC501 Defective PICK-UP

- 2-3 -

A

When laser does not light.

Is "2.4V~3.4V" applied to pin2 of IC502? ( OV 3.4V 2.4V)

YES

NO NO NO
Defective MICOM or CN503.

Did pickup return to innermost circular?

Is data transferred from MICOM IC ?

YES

YES

Does voltage appear at IC504 Pin 13, 14?

NO

Defective IC501,IC502

YES

Defective slide motor and/or connector.(CN501)

Does it stop at inner pick circular after shift?

YES

Is defect output from LMT SW applied to Pin 4 of PN505?

NO

Defective LMT SW and/or connector. (CN501,CN503)

OPEN

CLOSE YES

Defective MICOM.

YES NO
Is power supplied to laser Q501? (Q 501 collector: about 1.8V) Defective IC502

- 2-4 -

B

When laser light.

Laser lights

YES NO
Defective IC501

Check the signal FOCUS SEARCH of IC501 Pin 37 WAVEFORM #3

YES
Check the signal of IC504 Pin 15, 16 WAVEFORM #3

NO
Defective IC501

YES

Degraded laser diode Defective PICK-UP

C When SPINDLE motor dose not turn

Check the change for SPDO Voltage of IC501 Pin29 WAVEFORM #1

NO
Defective IC501

Check the change for SP +, SP -, Voltage of IC504 Pin11, 12 WAVEFORM #1

NO
Defective IC504

YES
Defective contact CN502 or Defective PICK-UP

- 2-5 -

WAVEFORMS OF MAJOR CHECK POINT
#1. SPINDLE DRIVE AND MOTOR WAVEFORM IC501(29), IC544(12) when TOC reading #2. RF WAVEFORM IC502(8), IC502(3) during TOC Reading

#3. FOCUS DRIVE AND MOTOR WAVEFORM IC501(37), IC504(15) · When focus search failed or there is no disc on tray

· There is disc on tray and focus search success

#4. TRACK DRIVE AND MOTOR WAVEFORM IC504(35), IC504(17) during TOC Reading

#5. MICOM INTERFACE WAVEFORM CN503(18,19,20,21) during normal play

- 2-6 -

INTERNAL BLOCK DIAGRAM of ICs
I IC401PD784214A 1) PORT ASSIGNMENT

- 2-7 -

2) PORT DESCRIPTION

- 2-8 -

- 2-9 -

I IC501 MN6627933CG

- 2-10 -

1) BLOCK DIAGRAM

- 2-11 -

FWD 1

REV

2

LDCONT 3

PS 4

INÅå 5

IN2

6

PR EVCC 7

AM5810

POWVCC12

8

VOL ( - )

9

VOL ( + ) 10

VO2 ( - ) 11

VO2 ( + ) 12

VO1 ( - )

13

VO1 ( + ) 14

2) PIN CONFIGURATION

1) BLOCK DIAGRAM

I IC504 AM5810

- 2-12 28

BIAS

27

OPIN4 ( + )

26

OPIN4 ( - )

25

OP OUT4

24

OPIN3 ( + )

23

OPIN3 ( - )

22

OPOUT3

21

MUTE

20

POWVCC34

19

GND

18

VO3 ( - )

17

VO3 ( + )

16

VO4 ( - )

15

VO4 ( + )

3) PIN DESCRIPTIONS
PIN No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 Pin Name FWD REV LDCONT PS IN1 IN2 PREVCC POWVCC12 VOL ( - ) VOL ( + ) VO2 ( - ) VO2 ( + ) VO1 ( - ) VO1 ( + ) VO4 ( + ) VO4 ( - ) VO3 ( + ) VO3 ( - ) GND POWVCC34 MUTE OPOUT3 OPIN3 ( - ) OPIN3 ( + ) OPOUT4 OPIN4 ( - ) OPIN4 ( + ) BIAS Description Input for loading forward Input for loading reverse Output control terminal for loading Control terminal for power saving mode Input 1 of CH1 Input 2 of CH2 Pre and loading unit power supply input terminal Power unit power supply input terminal (CH1, CH2) Inverted output of loading Not inverted output of loading Inverted output of CH2 Not inverted output of CH2 Inverted output of CH1 Not inverted output of CH1 Not inverted output of CH4 Inverted output of CH4 Not inverted output of CH3 Inverted output of CH3 Substrate ground Power unit power supply input terminal (CH3, CH4) Input for mute control Output of CH3 OP-ANP Inverting input of CH3 OP-ANP Not inverting input of CH3 OP-ANP Output of CH4 OP-ANP Inverting input of CH4 OP-ANP Not inverting input of CH4 OP-ANP Input of Bias-Amplifier

- 2-13 -

I IC505 AMC1117

1) BLOCK DIAGRAM

- 2-14 -

I IC601TDA7348D

- 2-15 -

I IC801 TA8275H

- 2-16 -

I IC901 PT6524 1) BLOCK DIAGRAM

2) PIN CONFIGURATION

- 2-17 -

- 2-18 -

BLOCK DIAGRAM
2(FL,FR)

IC601 TDA7438D
10,14 16 27 17 28

25,26

11,15

POWER AMP 17,19 IC803
7,9

L-SPEAKER FRONT R-SPEAKER L-SPEAKER REAR R-SPEAKER

LINE SW/E.VOLUME
2

23,24 2(RL,FR) 10,14

12,14

TDA8275HQ
21,23

8,12

TU101 11,12 CET85XX
16,17, 18,19 20 4,14 2(LR)

22

6,20

3,5

9.4V REG Q360,ZD361
2(RL,RR)

MUTE CCNTROL
Q720,721,722,723 4-CH (FL,FR,RL,RR)

LINE-OUT (OPTION)

CDC SIGNAL
9.4V 14V

RADIO VCC Q310,ZD313

POWER ON Q380,381

PN801 #16 BACK_UP

ANT CONTROL Q390,391

PN801 #10 PWR_ANT

POWER 5V Q282,Q283 RF IC AN22004A
24

REMOTE CONTROL Q320,321

PN801 #6 REMOTE

PICK-UP

RESET IC201

Q371 LCD CONTROL

ACC DETECTOR Q230,D231,D232

PN801 #14 ACC

58, 60

PHONE MUTE Q280,281

PN801 #5 PHONE

DSP IC (MN6627933)

72, 73, 74, 75, 76, 81

5V CONVERT Q260,D233 7.5V REG Q350,351

REG 9V IC403

DIMMER CONTROL Q371

PN801 #11 DIMMER

29, 31, 35, 37

3.3V REG IC505

54 68,69,70,71

2

55 10 24 3 11

90 6

91 4 43

5,6,23,26 9,10,11, 12,13,14

15,16,17,18

56,57 30,31,32,36

KEY MATRIX RESISTOR RADER
61~64

56~60 1~50

LCD DISPLAY

CD MECHA (CD303-C004A)

MOTOR DRIVE IC (AM5810)
4

7,8,20 1,2

14,19

U-COM IC401 uPD784214A

66,67 47,48

LCD DRIVER IC901 PT6524

38 29 15, 16, 17, 18 7 39

2-19

2-20

SCHEMATIC DIAGRAM
1. MAIN SCHEMATIC DIAGRAM

2-21

2-22

2. FRONT SCHEMATIC DIAGRAM

2-23

2-24

3. CDP SCHEMATIC DIAGRAM

2-25

2-26

PRINTED CIRCUIT DIAGRAM
1. MAIN P.C. BOARD (COMPONENT SIDE)

2-27

2-28

2. FRONT P.C. BOARD (TOP)

2. FRONT P.C. BOARD (BOTTOM)

2-29

2-30

3. CDP P.C. BOARD (TOP)

3. CDP P.C. BOARD (BOTTOM)

2-31

2-32

4. TRIM P.C. BOARD (TOP)

4. TRIM P.C. BOARD (BOTTOM)

5. LED P.C.BOARD (TOP)

5. LED P.C.BOARD (BOTTOM)

2-33

2-34

2-35

2-36

SECTION 3. CABINET MAINCHASSIS & MECHANISM
I EXPLODED VIEW
NOTE) Refer to "SECTION 4 REPLACEMENT PARTS LIST" in order to look for the part number of each part.

330

A50 281 283 280 A40 257 252 261 250 A49 282 255 267 263 269 294 296 251
276 272
295 A42

291

256

A43

A26 301

253

A41

A46
277

452 450 453

278 288 273 270 304 271

290

A45

302

3-1

3-2