Daewoo DV-6T712D, SD-3100K, DV-6T722D, SD-7100K Service Manual

S/M No. : VTB712DET0

Service Manual

MODEL: DV6T712D / DV6T112D

DV6T712P / DV6T112P DV6T712S / DV6T112S DV6T722D DV6T722P DV6T722S

DAEWOO ELECTRONICS CO., LTD.

Nov. 2002

http : //svc.dwe.co.kr

VCR

DVD

REPEAT

OPEN/CLOSE

DISPLAY

TITLE/PBC

OUTPUT

REC

PROGRAM

CLK/CNT

SPEED/ANGLE

TRACKING

TV/VCR

MARK

SYSTEM

PLAY/PAUSE

ZOOM

AUDIO

SUBTITLE

R E

T U

R N

/ O

SETUP

ENTER

✔

Caution

: In this Manual, some parts can be changed for improving, their performance without notice in the parts list. So, if you need the latest parts information,please refer to PPL(Parts Price List) in Service Information Center (http://svc.dwe.co.kr).

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

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

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

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

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

PCB CIRCUIT BOARD..............................................................................................................34

INSTRUMENT DISASSEMBLY...............................................................................................37

ELECTRICAL PARTSLIST.........................................................................................................45

CONTENTS

SPECIFICATIONS

DVD Audio output standards

Power 230V~, 50Hz Consumed electricity Hi-Fi : 24W, Mono : 23W Weight 5.7kg Dimension (W x H x D) 430mmx91mmx355.5mm Operative temperature +5°C~40°C Installation condition Horizontal / Relative humidity under 80% Signal type PAL/SECAM/MESECAM COLOR Antenna Input/output U/V-mixed: 75Ωunbalanced VIDEO input 1.0Vp-p (unbalanced, RCA JACK) AUDIO input -8.8dBm, RCA JACK VIDEO output (common use of DVD and VCR) VIDEO output terminal, 1.0 Vp-p unbalanced, RCA JACK, SCART JACK VIDEO output (DVD only) RGB output (75Ω In load R: 0.7Vp-p, G:0.7Vp-p, B:0.7Vp-p) AUDIO output (common use of DVD and VCR) Audio output terminal (2 kinds): -8.8dBm(VCR), 2Vrms(DVD), RCA JACK AUDIO output (DVD only) Analogue AUDIO output : 2.0Vrms

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 Tape speed SP: 23.39mm/s, LP: 11.70mm/s Playtime SP: 3hrs, LP: 6hrs (use of E180tape) Clock display 24 hrs Time Recording 8 programs a year Persistence in power failure 1min VIDEO S/N (VCR) Over 43dB(Standard recording) Resolution VCR Over 240 lines (Standard recording)

DVD Over 500 lines (Playback DVD) AUDIO (VCR) Over 65dB(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

ADVANTAGES OF THIS PRODUCT

• DVD, VCD, CD, CD-R(MP3), CD-RW, VHS

• DVD one-touch record function

• Watching DVD for recording broadcast

• Integrated remote control (VCR, DVD)

• VISS function

• Multiplex sound playback/record (Hi-Fi Model)

• High Sound Quality of 6 head Hi-Fi (Hi-Fi Model)

• Simple record function

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

• GUI (Graphical User Interface) through 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

• High bit / High sampling with 96MHz / 24bit Audio D/A Converter

• Coaxial, Optical digital Audio 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 output (x1)

ADVANTAGES OF THIS PRODUCT

• Slow Forward / Reverse playback (DVD)

• Fast Forward / Reverse playback

• Search of title, chapter, and time in DVD disc, and search of time and track 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, chapter and part for DVD / track, disc and part for VCD/CD)

• 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.

• 7 languages OSD (On Screen Display) function (DVD)

You can select and display OSD in 7 languages. (E/F/S/G/I/D/P)

• 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 12 languages. In the case of SVCD or VCD, it depends on the disc. (The number of audio languages depends on the software.)

• Multi Subtitle function (DVD)

The subtitle can be seem in up to 12 languages. In the case of SVCD or VCD, it depends on the disc. (The number of audio 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)

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 400~200V voltage

obtained at C805 +?

Output voltage of 2

parts is normal?

Check

rectifier diode of 2

parts ;

D821, D822, D823, D825,

D826, D827

Switching

pulse of IC801 pin#4 or

pin#5 is normal?

Exchange POWER CORD

Check

F801,L801,L802,D801.

Exchange rectifier diode of

parts ; D821, D822, D823,

D825, D826, D827.

Check IC801.

YES

2. SYSTEM CIRCUIT

TROUBLESHOOTING

No LED display.

Is 5V obtained at IC701

pin #9, 25?

Oscillation at IC701 pin #1?

Specific GRID/SEG doesn’t

function.

Check R705, L601.

Exchange IC701.

Check IC 701 pin #22~24, 27,

28, 30, 31.

Check IC 701 pin #10~12, 14~21.

YES

GRID output at PORT of

IC701?

YES

SEG output at PORT of IC701?

Exchange IC601.

YES

A. LED DISPLAY

TROUBLESHOOTING

No power compensation.

Voltage of power fail (IC601

pin#3) at micom is 0.7V over?

More than 3.2V is maintained

for 1 minutes at IC601 pin#37

during Power Cord Open.

Check R644.

YES

B. No power compensation.

YES

Check RESET circuit.

Exchange IC601.

TROUBLESHOOTING

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

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.

Re-adjust PATH.

C-1. Bad playback quality (1)

YES

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

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

Is Video Signal input at IC601

pin#50?

Is there Video output at IC601

pin#52?

Check TMI (RF101) Block.

Check Video Buffer Q156, Q157.

D. No broadcasting signal received

YES

TROUBLESHOOTING

Cassette tape isn’t

inserted.

Is 5V voltage obtained at

Loading parts IC601 pin#82?

Is 13V voltage obtained at

Capstan Motor pin#8?

Check at ON/OFF 12. Check (D822, Q851).

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

YES

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 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.

YES

Check C.FG(R660, C660)

and P603 pin#1.

TROUBLESHOOTING

G. DRUM Motor stops

H. CAPSTAN doesn’t rotate

CAPSTAN doesn’t rotate.

Is 14V voltage obtained at P603

pin#2?

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

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.

TROUBLESHOOTING

3. VIDEO circuit

EE screen doesn’t appear.

Is Video signal input at IC301

pin#48,50,52,54?

Is 5V obtained at IC301 pin#24,

42, 55, 72, 91?

Is signal input at IC302

pin#1,5,12,13,14,15?

Check LINE JACK and IF circuit.

Check DVD circuit.

Check POWER 5V.

Check LINE JACK and IF circuit.

Check DVD circuit.

A. EE screen doesn’t appear

YES

Is signal input at IC601 pin#50?

Check PCB Pattern.

Is signal output at IC302 pin#3?

Check IC302 pin#16VCC. Check

IC302 pin#9,10,11(control DC)

Is signal output at IC601 pin# 52?

Check IC604 pin#3(C sync).

Is signal output at IC301

pin# 62, 63?

Check VCC of IC301 and

pin #68,69.

Check RF Output.

Check LINE.

Is signal input at IC301 pin# 56?

YES

Check PCB Pattern.

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 IC302

pin#3?

Check and Replace IC301.

Check PCB Pattern.

Playback picture doesn’t

appear.

Is Envelope output at IC301

pin#79?

YES

Is Video signal input at IC601

pin#50?

Is 5V obtained at IC301

pin#91?

Is SW Pulse input at IC301

pin#70?

Is 5V obtained at IC301

pin#24,42,55,64?

Check POWER 5V.

Check IC601 pin#18.

Check and Replace HEAD.

Check POWER 5V.

YES

Does X301(4.43MHz) oscillate?

Check Pattern.

YES

Replace X301.

Is Video signal output at IC301

pin#65?

Check IC301 pin# 62.68,69,70.

YES

Check PCB pattern

IC302 pin#9,10,11(control

DC), 16(Vcc)

Check

Pattern.

Check IC604 PIN#3(C sync)

YES

TROUBLESHOOTING

Is 5V obtained at IC301

pin#91?

YES

Is IC301 pin#80 REC(H)

HIGH?

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 IC601 pin#22.

Check IC601 pin#18.

No recording.

Check EE MODE.

YES

Is FM signal output at IC301

pin#78?

Replace IC301.

YES

C. No recording

TROUBLESHOOTING

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?

Check IC 301.

D. No OSD(On Screen Display) appears

YES

Check IC 601.

TROUBLESHOOTING

4. AUDIO (Hi-Fi MODEL)

No sound in RF E-E

mode

Is there Audio at IC252

pin#4,11?

IC601 pin#27

A.Mute is L or

A. No sound in E-E mode

A. a.RF E-E

Check IC121, RF101 block.

Is 12V obtained at IC252

pin#16?

Is RF Audio signal output at

IC252 pin#3,13?

Check POWER circuit.

YES

IC601 pin#31 is H, pin#21

is H?

Is about 8V obtained at

IC252 pin#9?

Is about 8V obtained at

IC252 pin #10?

YES

Check IC601.

Check R646, R647.

C at Q904 is L or H?

YES

Check IC601.

Check Output JACK.

YES

Check Q904, Q905,

R937,R938,R939

Replace IC252.

YES

TROUBLESHOOTING

Is there Audio IC252 pin#2,15?

IC601 pin#27

A.Mute is L or

A. b. AV1 E-E

YES

Check Input JACK.

Is 12V obtained at IC252

pin 16?

Is RF Audio signal output at

IC252 pin#3,13?

Check POWER circuit.

YES

IC601 pin#31 is H,

pin#21is L?

Is about 8V obtained at

IC252 pin#9?

Is about 3.5V obtained

at IC252 pin #10?

YES

Replace IC252.

Check IC601.

Check R646, R647, R911,

R913.

C at Q904 is L or H?

YES

Check

IC601.

Check Output JACK.

Check

Q904,Q905,R9

37,R938,R939

YES

No sound in AV1 E-E

mode.

+ 40 hidden pages