DAEWOO DV6T811N-LT, DV6T813N-QJ, DV6T821N-QJ-X, DV6T813N-QJ-X, DV6T823N-QJ-M Service Manual

S/M No. : VTB811NET0

Service Manual

T

DAEWOO ELECTRONICS CO., LTD.

Jun. 2002

http : //svc.dwe.co.kr

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MODEL : DV6T811N-LT DV6T813N-QJ DV6T821N-QJ/X DV6T813N-QJ/X DV6T823N-QJ/M

1

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

ADVANTAGES OF THIS PRODUCT ......................................................................................3

TROUBLE SHOOTING .......................................................................................................................5

WAVEFORMS ...................................................................................................................................25

CIRCUIT DIAGRAM .........................................................................................................................28

PCB CIRCUIT BOARD.....................................................................................................................39

INSTRUMENT DISASSEMBLY......................................................................................................44

ELECTRICAL PARTSLIST................................................................................................................49

CONTENTS

1.

2.

3.

4.

5.

6.

7.

8.

2

SPECIFICATIONS

DVD Audio output standards

Power AC 120V, 60Hz Consumed electricity 24W (supplementary 2.5W) W eight 5.7kg Dimension (WxHxD) 430mmx91mmx355.5mm Operative temperature +5°C~35°C Installation condition Horizontal / Relative humidity under 80% Received channels VHF: 2-13 CH / UHF: 14-69 CH / Cable: 1-125 Signal type NTSC COLOR Antenna Input/output U/V-mixed: 75Ωunbalanced VIDEO input 1.0 Vp-p unbalanced, RCA JACK AUDIO input -8.8dBm, RCA JACK VHF output 3 or 4 CH VIDEO output (

common use of DVD and VCR

) VIDEO output terminal, 1.0 Vp-p unbalanced, RCA JACK

VIDEO output (DVD only) S-VIDEO output (75Ω In load Y : 1.0Vp-p, C:0.286Vp-p)

COMPONENT output (75ΩIn load Y: 1.0Vp-p, Pb:0.7Vp-p, Pr:0.7Vp-p)

AUDIO output (

common use of DVD and VCR)Audio output terminal (2 kinds): -8.8dBm(VCR), 2.0Vrms(DVD), RCA JACK

AUDIO output (DVD only) Analogue AUDIO output (2 CH): 2.0V rms

Digital audio output (OPTICAL, COAXIAL) Playable tape Very high dense tapes with VHS marks Playable disc DVD, VIDEO-CD, CD (12mm), CD (8mm), MP3, CD-R, CD-RW T ape speed Standard: 33.35mm/s, 3 times: 11.12mm/s Playtime Standard: 2hrs, 3 times: 6hrs (use of T120tape) Clock display 12 hrs AM/PM Time Recording 8 programs a year Persistence in power failure 1min VIDEO S/N (VCR) Over 45dB(Standard recording) Resolution VCR Over 220 lines (Standard recording)

DVD Over 500 lines (DVD Disc PLAY) AUDIO (VCR) Over 69dB(Hi-Fi), over 40dB(Mono) AUDIO (DVD) 90dB AUDIO dynamic range 90dB

Disc type

DVD VIDEO-CD CD

Analogue Audio output 48/96KHz sampling 44.1KHz sampling 44.1KHz sampling Digital Audio output 48KHz sampling 44.1KHz sampling 44.1KHz sampling Optical digital audio output 48KHz sampling 44.1KHz sampling 44.1KHz sampling

Output

1.

ADVANTAGES OF THIS PRODUCT

3

* DVD, VCD, CD, CD-R(MP3), CD-RW, VHS, S-VHS playback function

* DVD one-touch record function

* Watching DVD for recording broadcast

* Integrated REMOTE (VCR, DVD)

* Ultra power savings : less than 3W for stand-by mode

* VISS function

* Multiplex sound playback/record

* High Sound Quality of 6 head Hi-Fi

* One Touch timer Recording (OTR

)

* MP3 file playback function (CD-R disc having records of MP3 files

)

* Various video type-supported (AUTO, NTSC and PAL)

* GUI (Graphical User Interface) OSD (On Screen Display)

By using the [DISPLAY] button on the remote control, information on the DVD/VCD/CD player and disc, can be displayed on the TV screen.

* Screensaver function (DVD)

* 3D sound (3D sound effect using 2 speakers)

* High bit / high sampling with 27MHz / 10bit video encoder

This unit has 27MHz / 10bit capability, that enables the faithful reproduction of fine images.

* High bit / high sampling with 96KHz / 24bit audio D/A converter

With this 96KHz / 24bit linear Pulse Code Modulated signals, which constitute the highest specifications in the DVD standards, you can enjoy faithfully reproduced sound in all of its various modes. To support 96KHz sampling / 24bit sound, the shaping noise of this multi-level digital sigma type of D/A converter is kept flat up to 44KHz, thus preventing the important audio signals from being affected.

* Coaxial, Optical digital output (PCM, Dolby Digital, dts

)

You can enjoy high-level digital audio by connecting with amp embedded with Dolby Digital / dts decoder.

* Built-in Dolby Digital decoder (DVD)

* Analog audio 2-channels output for DOWNMIX (x1

)

* Composite video out (x1)

* S-Video out (x1)

2.

4

ADVANTAGES OF THIS PRODUCT

* Slow Forward / reverse (DVD) playback

* Fast Forward / reverse playback

* Search of title, chapter, and time in DVD disc, and search of track and time in VCD and CD

* Various TV aspect (DVD)

4:3 for Pan and Scan, 4:3 for Letter Box, and 16:9 for Wide

* Repeat playback (title and chapter for DVD, track and disc for VCD/CD)

* Bookmark function (DVD)

Playback position can be made to remember up to 3 positions for speedy search.

* Selective Play (DVD/VCD/CD)

You can select and play the desired title / chapter of DVD and track of Video CD/CD in STOP mode.

* 3 languages OSD (On Screen Display) function (DVD)

You can select and display OSD in 3 languages. (English, French, Spanish)

* Parental Lock function (DVD)

This function can prevent playback of software that may be unsuitable for children.

* Multi Audio function (DVD)

The audio soundtrack can be heard in up to 8 languages. In the case of SVCD or CVD, it depends on the disc. (The number of audio languages depends on the software.)

* Multi Subtitle function (DVD)

The subtitle can be seen in up to 32 languages. In the case of SVCD or CVD, it depends on the disc. (The number of subtitle languages depends on the software.)

* Multi Angle function (DVD)

This function allows you to choose the viewing angle of scenes which were shot from a number of different angles. (The number of angles depends on the software.)

* Screen zoom function (DVD/VCD)

* Thumbnail view function (in VCD with inactivated PBC)

5

TROUBLESHOOTING

1. POWER CIRCUIT

✓ CAUTION

You must use insulated trance during the first part test of POWER circuit.

Check IC601,IC701.

No power

POWER cord is ok?

Is 400~140V voltage

obtained at C805 +?

Output voltage of 2

nd

parts is normal?

Check

rectifier diode of 2

nd

parts ;

D821, D822, D823, D825,

D826, D827, D828.

Switching

pulse of IC801 pin#4 or

pin#5 is normal?

OK

Exchange POWER CORD

Check

G801,L801,L802,D801.

Exchange rectifier diode of

2ndparts ; D821, D822, D823,

D825, D826, D827, D828.

Check IC801.

NO

YES

NO

3.

2. SYSTEM CIRCUIT

6

TROUBLESHOOTING

No VFD display.

Is 5V obtained at IC701 pin#1?

Is -26V obtained at IC701

pin#16~17?

Oscillation at IC701 pin #2?

Is -22V, -18V obtained at F

F+?

Specific GRID/SEG doesn’t

function.

Check D701.

Check POWER circuit at -26V.

Check C704, IC701.

Check IC 701 pin #18~27.

Check IC 701 pin #28~43.

NO

YES

NO

GRID output at PORT of

IC701?

YES

SEG output at PORT of IC701?

Check POWER circuit at F-, F+.

Exchange IC601.

YES

A. VFD DISPLAY

NO

7

TROUBLESHOOTING

No power compensation.

Voltage of power fail (IC601

pin#100) at micom is 0.7V over?

More than 3.2V is maintained for 1 minutes at IC601 pin#37

during Power Cord Open.

Check R625.

NO

YES

B. No power compensation.

YES

Check RESET circuit.

NO

Exchange IC601.

Noise appears on the

playback screen.

Is noise diminished by tracking

adjustment.

Noise band is trembled up and

down?

Re-adjust PATH.

Is the height of CTL HEAD normal?

No dust?

Is there problem in CTL Input

circuit and amplifier.

YES

NO

Is there CTL pulse at IC601

pin#97?

Check IC601.

Noise appears on the screen

even though changing tape.

Re-adjust the height of AC

HEAD. Remove the dust.

Check C651, C652, R651~R653

IC601 pin #91, 92, 98.

NO

Re-adjust PATH.

C-1. Bad playback quality (1)

YES

8

TROUBLESHOOTING

Noise appears on the Full

playback screen.

Are SW pulse and HA SW

normal?

Recheck step C-1 (Bad

playback quallty (1)).

Check HEAD AMP connector

and HEAD.

YES

NO

ENVE Wave at PT01 pin #4?

Check VIDEO circuit.

Are there SW, HA SW pulse at

IC601 pin #16, 18?

Check PCB Pattern.

Check IC601.

C-2. Bad playback quality (2)

No broadcasting signal

received

Is the output at IC601 pin#

71(CLK), 72 (DATA) normal?

Is SIF,Video output at

TMI(RF101) pin#18,20 normal?

Check IC 601.

Check IC301.

Check IC601.

YES

NO

Is Video Signal input at IC601

pin#50?

Is there Video output at IC601

pin#52?

Check TMI (RF101) Block.

NO

Check Video Buffer Q101

D. No broadcasting signal received

YES

NO

YES

9

TROUBLESHOOTING

Cassette tape isn’t

inserted.

Is 5V voltage obtained at

Loading parts IC604 pin#82?

Is 13V voltage obtained at

Capstan Motor pin#8?

Check at ON/OFF 12.

Check (D822, Q821).

Connect Capstan and Loading Motor. Check connector and Capstan Motor.

YES

NO

Is 12V voltage obtained at Each

parts of Loading Motor?

Replace Loading Motor.

Check D851 and POWER circuit.

E. No CASSETTE Loading

YES

F. AUTO STOP in Playback mode

VCR stops automatically

in playback mode.

Check R656,C659 and P603 pin#11

Check P502 connector.

Check S603, S604 REEL Sensor.

Is D.PG/FG pulse at IC601

pin#90 normal ?

Is C. FG pulse at IC601

pin#87 normal ?

Is there REEL Pulse at IC601

pin#79, 80?

Check and replace IC601.

NO

YES

NO

Check C.FG(R665, C660)

and P603 pin#1.

NO

10

TROUBLESHOOTING

G. DRUM Motor stops

H. CAPSTAN doesn’t rotate

CAPSTAN doesn’t rotate.

Is 14V voltage obtained

at P603 pin#2?

YES

NO

YES

Is Capstan PWM fit to

IC 601 pin#77?

Is 3.2V voltage obtained

at P603 pin#5?

Is 2~3V voltage obtained

at P603 pin#9?

Check P603 Connector and

Capstan Motor.

Check 14V.

(Q856,Q857,Q852)

Check Capstan FG

(IC 601 87).

Check R665, R664, R663,

R666, C665.

Check R661, R667, C664.

DRUM Motor stops.

Is 13V voltage obtained at

P603 pin#8?

YES

NO

YES

Is DRUM PWM fit to IC 601

pin#76?

Is 1.2V voltage obtained at

P603 pin#12?

Check Capstan Motor and

DRUM Motor.

Check ON/OFF 13V

(D851, Q856).

Check DRUM PG/FG(IC 601 90).

Check R657, R658,C661,C668.

NO

11

TROUBLESHOOTING

3. VIDEO circuit

A. EE screen doesn’t appear

EE screen doesn’t appear.

Is Video signal input at IC301

pin#48,50,52,54?

Is 5V obtained at IC301

pin#54, 42, 55, 72?

Is signal output at IC301

pin#65?

Is signal input at IC601

pin#50?

Check LINE JACK and IF circuit.

Check DVD circuit.

Check POWER 5V.

Check IC301

pin #70,62,68,69.

NO

YES

NO

Check PCB Pattern.

YES

Is signal output at IC301

pin#61 or #63?

YES

NO

Check IC301

pin #68,69,70,62

Signal output at IC301 pin#65 is

transferred to IC301 pin#56?

YES

NO

Check PCB Pattern.

Is signal input at IC302

pin#12 or #13?

YES

NO

Check PCB Pattern.

Is signal input at IC302

pin#14?

YES

NO

Check IC302 pin #11

Is Y signal input at IC604

pin#6?

YES

NO

Check PCB Pattern.

Is C-Sync signal output at

IC604 pin#3?

YES

NO

Is 5V obtained at IC604

pin#7?

Is C-Sync signal input at

IC601 pin#58?

YES

NO

Check PCB Pattern.

Is C-Sync signal input at IC601

pin#58?

YES

Check PCB Pattern.

NO

Is signal output at IC601

pin# 52?

Is 5V obtained at IC601

pin#53,98,99?

YES

NO

Check POWER circuit.

Check RF Output.

Check

NO

Check IC 601

YES

12

TROUBLESHOOTING

B. Playback picture doesn’t appear

YES

Is Y signal output at IC301

pin#46?

Is Y signal input at IC301

pin#43?

Is Video signal output at IC301

pin#61?

Check and Replace IC301.

Check PCB Pattern.

Playback picture doesn’t

appear.

Is Envelope output at IC301

pin#79?

NO

YES

Check Sync separate circuit

and OSD circuit

Is 5V obtained at IC301

pin#91?

Is SW Pulse input at IC301

pin#70?

Is 5V obtained at IC301

pin#21, 57?

Check POWER 5V.

Check IC601 pin#18.

Check and Replace HEAD.

Check POWER 5V.

YES

NO

Does X301(3.58MHz) oscillate?

Check Pattern.

NO

YES

NO

YES

Replace X301.

Is Video signal output at IC301

pin#65?

Check IC301 pin# 62.68,69,70.

NO

YES

13

TROUBLESHOOTING

Is 5V obtained at IC301

pin#91?

YES

NO

YES

Is IC301 pin#80 PB(H) LOW?

Is VIDEO SW Pulse input at

IC301 pin#70?

Is REC signal input at IC301

pin#94, 95, 89, 90?

EP MODE: 89, 90 Pin

SP MODE: 94,95Pin

Check HEAD and Connector.

Is signal input at IC301 pin#

48, 50, 52, 54?

Check POWER circuit.

Check PB(H) circuit

Check IC601 pin#18.

No recording.

Check EE MODE.

YES

Is FM signal output at IC301

pin#78?

Replace IC301.

NO

YES

C. No recording

14

TROUBLESHOOTING

E. No sound in broadcasting (Stereo)

Is 5V obtained at IC101

pin#1, 11, 33?

Oscillation of IC101 pin#5,6?

YES

NO

YES

Is SIF output from RF101

pin#18 to IC101 pin#2?

Is AUDIO output at IC101

pin#26, 27?

Check IC251 pin#2,3.

Check POWER circuit.

Exchange X101.

Check RF101.

Exchange IC101.

NO

Is Video signal input at IC601

pin#50?

Check POWER circuit.

No OSD appears.

Is 5V obtained at IC601 pin#

53, 98, 99?

Is Video signal output at IC601

pin#52?

NO

Replace IC601.

D. No OSD(On Screen Display) appears

YES

NO

Check IC 601.

15

TROUBLESHOOTING

4. AUDIO

No sound in RF E-E

mode

Is there Audio at IC252

pin#5,14?

IC601 pin#27

A.Mute is L or

H?

A. No sound in E-E mode

A. a.1 RF E-E

NO

Check signal flow circuit

from IC251 to IC252.

Is 12V obtained at IC252

pin#16?

Is RF Audio signal output at

IC252 pin#3,13?

Check POWER circuit.

NO

YES

NO

IC601 pin#20 is H,

pin#21is L?

Is about 3.5V obtained at

IC252 pin#9?

Is about 8V obtained at

pin #10?

YES

Check IC601.

Check

R298,R299,R646,R647.

NO

C at Q258 is L or H?

YES

Check IC601.

Check Output JACK.

H

L

YES

Is Audio signal output at IC251

pin#19, 20?

Are CLK and DATA obtained

at IC251 pin#42,43?

NO

Is 5V obtained at IC251

pin#40?

Is there Audio at IC251 pin#2,

3 in RF mode?

Check IC101 and RF101

Block(Ad2).

NO

Replace IC251.

NO

YES

Is 12V obtained at IC251

pin#34?

NO

YES

Check POWER circuit.

YES

Check

Q257,Q258,R24

0, R241, R242

L

Replace IC252

YES

16

TROUBLESHOOTING

Is there Audio IC252 pin#5, 14?

IC601 pin#27

A.Mute is L or

H?

A. b. LINE1 E-E

YES

NO

Check signal flow circuit from

IC251 to IC252.

Is 12V obtained at IC252

pin 16?

Is RF Audio signal output at

IC252 pin#3,13?

Check POWER circuit.

YES

NO

IC601 pin#20 is H,

pin#21is L?

Is about 3.5V obtained

at IC252 pin#9?

Is about 8V obtained at

pin #10?

YES

Replace IC252.

Check IC601.

Check R298, R299, R646,

R647.

NO

C at Q258 is L or H?

YES

Check

IC601.

Check Output JACK.

Check Q257,Q258,R2 40,R241,R242.

H

L

YES

No sound in LINE1 E-E

mode.

Is 12V obtained at IC251

pin#34?

NO

Is 5V obtained at IC251

pin#40?

Check POWER circuit.

YES

NO

Are CLK and DATA obtained at

IC251 pin#42,43?

Check Input LINE1

JACK

Replace IC251

NO

Is Audio signal output at IC251

pin#19, 20?

Is Audio signal at IC251

pin#6, 7 in LINE1 mode?

17

TROUBLESHOOTING

Is there Audio at IC252

pin#4,11 in LINE2 mode?

IC601 pin#27

A.Mute is L or

H?

NO

Check Input LINE2 JACK.

Is 12V obtained at IC252

pin#16?

Is LINE2 Audio signal output

at IC252 pin#3,13?

Check POWER circuit.

NO

YES

NO

IC601 pin#20 is H?

pin21 is H?

Is about 8V obtained at

IC252 pin#9? Is about 8V

obtained at pin#10 ?

Replace IC252.

Check IC601.

Check

R298,R299,R646,R647.

NO

C at Q258 is L or H?

YES

Check IC601.

Check Output JACK.

Check Q257,Q258,R2 40,R241,R242.

H

L

YES

A. c. LINE2 E-E

No sound in LINE2 E-E

mode.