Daewoo DV-S103W, DV-S123W. Service Manual

S/M No. : VS123MUEF1

Service Manual

Video Cassette Recorder

Multi Models(S2-MECHA)

Model:PAL/MESECAM/NTSC (DV-S123W Series) (DV-S103W Series)

PAL-N/NTSC (DV-S123A Series) (DV-S103A Series)

NTSC Only Models (DV-S123N Series) (DV-S103N Series)

DAEWOO ELECTRONICS CO., LTD.   URL : http://svc.dwe.co.kr

TABLE OF CONTENTS

SAFETY&PRECAUTIONS ............................................................................................... 2

EXTERNAL VIEWS ........................................................................................................ 4

1. FRONT VIEWS FUNCTION ............................................................................................................... 4

2. REAR VIEWS FUNCTION ................................................................................................................. 5

GENERAL ADJUSTMENT .............................................................................................. 6

SPECIFICATIONS ....................................................................................................... 7

TROUBLE SHOOTING GUIDE ........................................................................................ 8

1. TROUBLE SHOOTING FLOW CHART ................................................................................................ 8

2. VOLTAGE CHART ........................................................................................................................... 25

3. WAVEFORMS ON VIDEO CIRCUIT .................................................................................................. 26

4.¥ì-COM PIN ASSIGNMENT ........................................................................................................... 29

PRINTED CIRCUIT BOARD ............................................................................................ 32

1. PCB MAIN ..................................................................................................................................... 32

2. PCB POWER(SMPS) ........................................................................................................................ 33

CIRCUIT DIAGRAM ..................................................................................................... 34

1. CONNECTION DIAGRAM .............................................................................................................. 34

2. POWER CIRCUIT ............................................................................................................................ 35

3. SERVO SYSCON CIRCUIT ............................................................................................................... 36

4. AV INPUT OUTPUT CIRCUIT .............................................................................................................. 37

5. VIDEO AUDIO CIRCUIT .................................................................................................................. 38

EXPLODING VIEWS & PARTS LIST ................................................................................. 39

1. PACKING AS ................................................................................................................................. 39

2. SET TOTAL ASSEMBLY ..................................................................................................................... 40

3. FRONT PANEL ASSEMBLY ............................................................................................................... 41

ELECTRICAL PARTS LIST ............................................................................................... 43

1. PCB MAIN AS ................................................................................................................................ 43

2. PCB AUTO VOLT REGULATOR AS ................................................................................................. 48

3. DIFFERNCE PARTS LIST ................................................................................................................... 49

1

SAFETY&PRECAUTIONS

SAFETY CHECK AFTER SERVING

Examine the area surrounding the repaired location for damage or deterioration. Observe that screw, parts and wires have been returned to original positions. Afterwards, perform the following tests and conform the specified values in order to verify compliance whit safety standards.

1. Insulation resistance test Confirm the specified insulation resistance between power cord plug prong and externally exposed parts of the set (RF terminals, antenna terminals, video and audio input and output terminals, microphone jacks, earphone jacks, etc.) is

greater than values given in table 1 below.

2. Dielectric strengthen test Confirm specified dielectric strengthen between power cord plug prongs and exposed accessible parts of the set (RF terminals, antenna terminals, video and audio input output terminals, microphone jack, ear phone jacks, etc.) is greater than values given table 1.

3. Clearance distance When replacing primary circuit component, confirm specified clearance distance (d), (d’) between soldered terminals, and between terminals and surrounding metallic parts. See table below.

Rating for selected areas

AC Line Voltage Region

100V Japan

110 to 130V

* 110 to 130V

200 to 240V

* : Class model only

USA & Canada

Latin America

Europe

Australia

Insulation

Resistance

¡Ã1§Û

/500V DC 1

- 900V AC 1min.

¡Ã10§Û

/500V DC 4§Ç AC 1min.

Dielectric

Strength

§Ç

AC 1min.

Clearance

Distance(d),(d)

¡Ã

3

¡Ã

3.2

¡Ã

6(d)

¡Ã

8(d’)

(a :Power cord)

NOTE

This table is unofficial and for reference only. Be sure to confirm the precise values for your particular country and locality

2

SAFETY&PRECAUTIONS

4. Leakage current test Confirm specified or lower leakage current between B(earth ground, power cord plug prongs) and externally exposed accessible parts (RF terminals, antenna terminals, video and audio input output terminals, microphone jacks, earphone jacks, etc.) Measuring method:(Power ON) Insert load Z between B(earth ground, power cord plug prongs) and exposed accessible parts. Use on AC voltmeter to measure across both terminals of load Z. See figure2 and following table.

Leakage current ratings for selected are as

AC Line Voltage Region Load Z Leakage Current(i) Clearance Distance(d),(d’)

100V Japan

1

§Ú

15k

110 to 130V USA &Canada

110 to 130V 200 to 240V

Europe

Australia

1

2

50

§Þ

§Ú

NOTE

This table is unofficial and for reference only. Be sure to confirm the precise values for your particular country and locality.

i ¡Â1§Ì

i ¡Â

i ¡Â2§Ì

i ¡Â

0.7§Ì peak

i ¡Â1§Ì

rms

0.5§Ìrms

0.7§Ìpeak dc

dc

Exposed accessible parts

Antenna earth terminals

Other terminals

3

EXTERNAL VIEWS

1. FRONT VIEWS FUNCTION

DV-S103W FRONT VIEW

DV-S123W FRONT VIEW

POWER REVIND / REVIEW STOP / EJECT FAST FORWARD / CUE RECORD PLAY BACK FRONT VIDEO AUDIO INPUT JACK

4

2. REAR VIEWS FUNCTION

DV-S103W & DV-S123W PHONE JACK TYPE REAR VIEW

AUDIO/ VIDEO IN/OUT JACK ANT INPUT DC12V INPUT JACK RE OUTPUT

EXTERNAL VIEWS

DV-S103W & DV-S123W SCART JACK TYPE REAR VIEW

EURO AUDIO / VIDEO IN/OUT JACK ANT INPUT DC12V INPUT JACK RF OUTPUT

DV-S103A & DV-S103N REAR VIEW

AUDIO / VIDEO IN/OUT JACK ANT INPUT DC12V INPUT JACK RF OUTPUT

CH 3 OR 4 SELECT SWITCH

5

GENERAL ADJUSTMENT

SERVO CIRCUIT

ITEM

Playback

Phase

ADJUSTMENT

PARTS

R591

LOCATION OF ADJUSTMENT PARTS OBSERVATION WAVEFORM

A/V JACK

MOD

TJ391

(VIDEO OUT)

PRE-AMP

FRONT

ADJUSTMENT PROCEDURE

CHECK POINT TEST EQUIPMENTS MODE TEST TAPE

TJ591(V.SW)

TJ391(VIDEO OUT)

SMPS

TJ591

(V. SW)

R591

Oscilloscope Play DP-2

1. Preparation Playback the test tape (DP-2). Set the oscilloscope to the CHOP mode. Connect CH1 to the V.SW PULSE (TJ591) and CH2 to the VIDEO OUT (TJ391) and trigger the scope with the signal from CH1.

2. Adjustment Adjust R591 to the positive rising edge of V.SW PULSE at 6.5H ±0.5H from the V-SYNC.

3. Adjustment Inspection Standard

6.5H ± 0.5H

4. REMARKS

6

SPECIFICATIONS

SYSTEM

Video signal RF Output

VIDEO

Input : Video line in Output : Video line out Recording system Signal to Noise ratio

Horizontal Resolution

AUDIO

Input : Audio line in Output : Audio line out Frequency Response Signal to Noise Ratio Audio Distortion

TAPE TRANSPORT

Format Tape Width Tape Speed

Maximum Recording Time FF/REW time

GENERAL

Power Requirements Power Consumption

Temperature Operating position

DIMENSIONS

Carton size (W x H x D) Set size (W x H x D) Weight

PAL/MESECAM/NTSC color (for DV-S103W Series) PAL-N/NTSC color (for DV-S103A Series) NTSC color (for DV-S103N Series) PAL-G/K/I UHF CH22 ~ CH40 (for DV-S103W & DV-S103S Series) NTSC-M VHF CH3 OR CH4 (for DV-S103A & DV-S103N Series)

75 ohms unbalanced, sync. 75 ohms unbalanced, sync. Negative Rotary tow-head helical scan More than 45dB (PAL-SP) More than 43dB (NTSC-SP) 240 Lines (PAL-SP) 210 Lines (NTSC-SP)

-8dBm, (CENELEC standard), more than 47, unbalanced

-6dBm, (CENELEC standard), less than 1, unbalanced 100Hz ~ 8KHz ( for PAL-SP) 100Hz ~10KHz (for NTSC-SP) More than 38dB (for PAL-SP) More than 40dB (for NTSC-SP) Less than 3% (SP)

VHS standard

12.65 (1/2) PAL SP : 23.39mm/sec PAL LP :11.70mm/sec NTSC-SP : 33.35/sec. NTSC-EP : 11.12/sec. 480min, with E-240 tape (PAL-LP) 540min, with T-180 tape (NTSC-EP) about 5min, with T-120 tape

AC 90V ~ 260V, 50/60Hz DC12V ~ 16V (2A) Max. 14W (in REC mode) 5°C ~ 35°C (Operating)

-20°C ~ 60°C (Storage) Horizontal only

417 x 172 x 369 mm 280 x 91 x 347 mm

3.5 Kg

INPUT/OUTPUT JACK TYPE

Model For CIS For Middle East / Asia

Jack Type SCART Type

RCA Jack

(Phone Jack)

7

TROUBLE SHOOTING GUIDE

1. TROUBLE SHOOTING FLOW CHART

A. POWER CIRCUIT

When changing the parts which are out of order, first, remove the power plug from the socket and then discharge the voltage across between both terminals of C803. (Use an external approximately 20 resistance) When check the primary circuit by using the oscilloscopes insulate the oscilloscope properly (Use the insulating transformer)and GND must be connected GND into the primary GND (But there is no connection when checking the secaondary circuit. When changing M801, check FUSE and ceramic resistor properly.

A-1. CHECKING THE PRIMARY CIRCUIT.

No output voltage

YES

Is the voltage applied to

CN11?

YES YES

Is the voltage +15V at pin3

of IC11?

YES YES YES

Check the secaondary

circuit

NO

Check F801, L801, L802

C803, D801, R801

Is the voltage above 10V

at pin3 of IC11?

( A )

NO

A-2. CHECKING THE SECONDARDARY CIRCUIT.(Before secondary circuit open).

(A)

YES

Check each output voltage

YES

NO

Check transformer of no

output stages

Check the diode of no

output stages

Is the voltage 0V at pin3

of IC11?

Check R14, R15, T11

R13, D11, L12

YES

Check the CN11

YES

Check the coil, condensor

of no output stages

8

A-3. CHECKING THE DC - INPUT CIRCUIT.

Do not turn on the front

DISPLAY

YES

TROUBLE SHOOTING GUIDE

Check the polarity of

DC adaptor

YES

Is Vcc input at pin1 of

IC803?

YES

Check SERVO/SYSCON

circuit

YES

Check SERVO/SYSCON

circuit

B. LED DISPLAY CIRCUIT.

LED does not operate

properly.

YES

NO

Change the DC adptor

Check JK801 and pattern

Is 1.25V input at pin4 of

Is +5.1V supplied from

D510 cathod to L701?

IC803?

NO

Check R805, R806 and

R807

Check power module

Is +5.1V supplied to the

collectors of Q701~Q706?

YES

Are the signals supplied

from u-com to the bases

of Q701~Q706?

YES

Are the signals supplied

from u-com to the bases

of Q707~Q713?

YES

Are the signals supplied

To the LED(G701)?

YES

Check G701 and pattern

NO

Check L701

Check u-com

Check Q701~ Q713 and

patterns

9

TROUBLE SHOOTING GUIDE

C. SERVO/SYSCON CIRCUIT

C-1. FRONT KEYS

Front keys do not operate

correctly

YES

Is +5.1V supplied to pin18

of IC501?

YES

Is +5.1V supplied to the

emitter of Q502?

YES

Is +5.1V input at pin41 of

IC501?

YES

Check IC501

C-2. PICTURE IN PB MODE

PB picture is not good

YES

Noise appears although

adjusting tracking?

NO

Check power module

Check u-com, JP053 and

JP059

Check Q502 and circuit

Adjust tracking

Noise appears although

Change cassette tape

YES

Check and re-adiust the

path of DECK

YES

Is CTL pulse output at

NO

pin1 of IC505?

YES YES

Is CTL pulse input at

NO

pin29 of IC501?

YES

The voltage of IC501's

NO

pin18 is not changing?

YES

Check IC501

AC HEAD's height is

normal and there is not

dust?

Check C556, C533 and

D505

Check power module

10

NO

Adjust the head height

and remove dust

Check IC505 and adjacent

YES

circuit

C-3. PICTURE IN PB MODE

PB picture is not good

YES

TROUBLE SHOOTING GUIDE

Noise appears on the

screen on the whole?

YES YES

Is V-SW puls applied to

PREAMP circuit?

YES

Is DC-ENVE waveform

input at pin39 of IC501?

YES

Check video circuit

C-4. AUTOSTOP IN PB MODE

Autostop during playback

NO

Noise appears on the

screen at the bottom?

NO

Is V-SW pulse supplied

From pin46 of IC501?

NO

Check R524 and pattern

Is DC-ENVE waveform

output at pin6 of IC401?

YES

NO

Check flow C-2

Adjust the PG delay

Check D.PG input at pin13

of IC501 and P502

NO

Check video circuit

(R591)

YES

Are S&T pulses input at

pin1 and pin7 of IC501?

YES

Is D.FG input at pin30 of

IC501?

YES

NO

Check reel sensors

Is D.PWM output at pin33

of IC501?

YES

Check IC501 Check P502 and R536

NO

Check IC501

11

TROUBLE SHOOTING GUIDE

C-5. CASSETTE IS NOT INSERTED

Cassette is not inserted

YES

Is ON/OFF 12V supplied

NO

at pin7 of IC503?

YES

CAM data are changed

NO

when CST IN?

YES

Is +5V applied to pin6

NO

of IC503 when CST IN?

YES YES

Is 8.2V supplied to pin4

of IC503?

YES

Are control signals output

NO

at pin76 and 78 of IC501?

NO

at pin2 and 10 of IC503

Check power module

Check P504

Is control signal output

at pin76 of IC501?

Check pattern and R529

Are control signals output

YES

Check IC503

NO

Check DECK

Check IC501

Check IC503

YES

Check D504, D508 and

D503

YES

Check P503 and L/C

Motor.

12

C-6. CAPSTAN MOTOR

Capstan M/T loading stops

YES

TROUBLE SHOOTING GUIDE

Is +14V supplied to pin7

NO

of P501?

YES

Is the input of P502's pin6

NO

2.5 ~ 3.5V?

YES

Is pin4 of P501 2.5V?

YES

Is C.PWM output at pin34

NO

of IC501?

YES

Check P501, R516, R526

and C526

C-7. DRUM & CAPSTAN M/T IN REC MODE

Drum M/T and capstan

M/T rotate at reular speed

(IN REC MODE)

Check power module

Check circuit of R555,

R556 and R557

Check R559 and R560

Check IC501

YES

Is C.SYNC applied to the

base of Q501?

YES

Is V.SYNC input at pin28

of IC501?

YES

Check motors

NO

Check C.SYNC of IC301

and pattern

Check Q501 and R527

13

TROUBLE SHOOTING GUIDE

C-8. EMERGENCY

Emergency mode when

plugging (power cord)

YES

Is +5.1V applied to pin18

of IC501?

YES

Does X501 crysyal

oscillate?

YES

Are CAM SW data cor-

rect?

YES

NO

Check power module

Check IC501 and crystal

circuit

Recheck P504 and CAM

SW contact

Check IC503 and IC501

C-9. VCP DOES NOT OPERATE (ALTHOUGH POWER CIRCUIT IS NORMAL.)

VCP does not operate after

power cord plugging

YES

Is +5.1V supplied to pin1

of IC502?

NO

Check power module

YES

Is +5V input at pin63 of

IC501?

YES

Check flow C-8

NO

Check IC502 and pattern

14

D. AUDIO CIRCUIT

D-1. PB MODE

No sound in the PB mode

YES

TROUBLE SHOOTING GUIDE

NO

Is the output at pin77 of

Is +5V supplied to pin76 of

IC301?

YES YES

Check R217, R218, L602

Is voltage less than 0.2V

and pattern

Is collector of Q204 GND?

IC301 and to pin2 of

T201?

at pin80 of IC301?

YES

Check pattern and AC

Head

NO

Check IC802 and adjacent

NO

Are CLK and DATA

applied to pin63 and 64 of

YES NO

Check IC501

NO

Check Q202, Q203 and

circuit

IC301?

Q204

15