Daewoo DSC-34W70N User manual

S/M No. : DSC120BEF0
Service Manual
Model:DSC-34W70N
Release 1
HDTV Monitor
Chassis : SC-120
Specification
Power Requirement AC 120V, 60Hz
Power Consumption 210watts
General Dimensions(W/H/D) 41”W x 26.2”H x 24.6”D
Weight 81Kg (178.61bs)
Antenna One 75ohm external input terminal for
UHF/VHF/Cable
Screen Size 34”(diagonal), 16:9 Aspect Ratio
Picture Display Format DTV : 1080I @ 33.75KHz
NTSC/DVD : 480p @ 31.5KHz
Horizontal Resolution 800 Lines
Sound System Dolby Pro Logic
Sound NTSC Audio Multi CH TV Stereo(MTS) /
Second Audio Program(SAP)
Audio Power 8W/ch (Main L/R), 5W/ch (Center)
Rear
RF Antenna Input
NTSC A/V In 2each (Video/L/R)
1each (S-Video/Video/L/R)
NTSC A/V Monitor Out 1each (Video/L/R)
Inputs/ HD Component In 1each (Y/Pb/Pr)
Output DVD Component In 1each (Y/Cb/Cr)
Surround Channel Out 1each (SL/SR)
Sub woofer Out 1each
Side
NTSC A/V In 1each (S-Video/Video/L/R)
Headphone 1each (L/R)
DAEWOO ELECTRONICS CO., LTD.
http:// svc.dwe.co.kr Nov. 2001

- 1 -
1. Product Safety 2
2. Specifications 4
3. Remote Control Overview 5
4. Limited Warranty 6
5. Service Mode 7
6. General Adjustment 10
7. Special Adjustment (When replacing new circuits boards) 15
8. Troubleshooting Charts 16
9. Parts List 25
10. Circuit Diagram
10-1. Power Circuit 47
10-2. Main Circuit 48
10-3. Audio Circuit 49
10-4. 3D Comb Filter Circuit 50
10-5. Main Video Circuit 51
10-6. Sub Video Circuit 52
10-7. Scan Rate Converter Circuit 53
10-8. RGB Processor Circuit 54
10-9. AV Circuit 55
10-10. Union Circuit 56
10-11. Signal Flow Diagram 57
11. Exploded View 58
✔ 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).

1. PRODUCT SAFETY SERVICING GUIDELINES FOR COLOR TELEVISION RECEIVERS
- 2 -
CAUTION : Do not attempt to modify this product in any way.
Unau-thorized modifications will not only void the warranty, but
may lead to your being liable for any resulting property damage
or user injury. Service work should be performed only after you
are thoroughly familiar with all of the following safety checks
and servicing guide-lines. To do otherwise, increases the risk of
potential hazards and injury to the user.
SAFETY CHECKS
After the original service problem has been corrected, a check
should be made of the following:
SUBJECT : FIRE & SHOCK HAZARD
1.Be sure that all components are positioned in such a way as
to avoid possibility of adjacent component shorts.
This is especially important on those chassis which are
transported to and from the repair shop.
2.Never release a repair unless all protective devices such as
insulators, barriers, covers, shields, strain relief, and other
hardware have been reinstalled per original design.
3.Soldering must be inspected to discover possible cold solder
joints, frayed leads, damaged insulation (including A.C. cord),
solder splashes or sharp solder points. Be certain to remove
all loose foreign particials.
4.Check for physical evidence of damage or deterioration to
parts and components, and replace if necessary follow
original layout, lead length and dress.
5.No leads or components should touch a receiving tube or a
resistor rated at 1 watt or more. Lead tension around
protruding metal surfaces must be avoided.
6.All critical components such as fuses, flameproof resistors,
capacitors, etc. must be replaced with exact factory types.
Do not use replacement components other than those
specified or make unrecommended circuit modifications.
7.After re-assembly of the set always perform an A.C. leakage
test on all exposed metallic parts of the cabinet, (the channel
selector knob, antenna terminals, handle and screws) to be
sure the set is safe to operate without danger of electrical
shock. Do not use a line isolation transformer during this test.
Use an A.C. voltmeter, having 5000 ohms per volt or more
sensitivity, in the following manner : connect a 1500 ohm 10
watt resistor, paralleled by a 15 mfd. 150V A.C. type
capacitor between a known good earth ground (9water pipe,
conduit, etc.) and the exposed metallic parts, one at a time.
Measure the A.C. voltage across the combination of 1500
ohm resistor and 0.15 MFD capacitor. Reverse the A.C. plug
and repeat A.C. voltage measurements for each exposed
metallic part. Voltage measured must not exceed 0.75 volts
R.M.S. This corresponds to 0.5 milliamp A.C. Any value
exceeding this limit constitutes a potential shock hazard and
must be corrected immediately.
GRAPHIC SYMBOLS :
The lightning flash with arrowhead symbol,
within an equilateral triangle, is intended to
alert the service personnel to the presence of
uninsulated “dangerous voltage” that may be
of sufficiency magnitude to constitute a riskof
electric shock.
The exclamation point within an equilateral
triangle is intended to alert the service perso-
nnel to the presence of important safety
information in service literature.
Fuse symbol is printed on pcb adjacent to the
fuse, with “RISK OF FIRE REPLACE FUSE
AS MARKED”. The symbol is explained in the
service manual with the following wording or
equivalent.
CAUTION : FOR CONTINUED PROTECTION AGAINST
FIRE HAZARD, REPLACE ONLY WITH SAME TYPE (6.3A,
125V)” and
“ATTENTION: AFIN D’ ASSU UNE PROTECTION
PERMANENTE CONTRE LES RISQUES D’ INCENDIE,
REMPLACER UNIQUE-MENT PAR UN FUSIBLE DE MEME
TYPE ET DE “6.3A, 125V”.
SUBJECT : X-RADIATION
1.Be sure procedures and instructions to all service
personnel cover the subject of X-rays in current T.V.
receivers is the picture tube. However, this tube does not
emit X-rays when the high voltage is at the factory
specified level. The proper value is given in the appli-
cable schematic. Operation at higher voltages may cause
a failure of the picture tube or high voltage supply and,
under certain circumstances, may produce radiation in
excess of desirable levels.
2.Only factory specified C.R.T. anode connectors must be
used. Degaussing shields also serve as X-ray shield in
color sets. Always re-install them.
3.It is essential that the serviceman has available an
accurate and reliable high voltage meter. The calibration of
the meter should be checked periodically against a
reference standard. Such as the one available at your
distributor.
4.When the high voltage circuitry is operating properly there
is no possibility of an X-radiation problem. Every time a
color chassis is serviced, the brightness should be run up
and down while monitoring the high voltage with a meter to
be certain that the high voltage does not exceed the
specified value and that it is regulating correctly. We
suggest that you and your service organization review test
procedures so that voltage regulation is always checked
as a standard servicing procedure. And that the high
voltage reading be recorded on each customer’ s invoice.
5.When troubleshooting and making test measurements in a
receiver with a problem of excessive high voltage, avoid
being unnecessarily close to the picture tube and the high
voltage compartment. Do not operate the chassis longer
than is necessary to locate the cause of excessive voltage.
6.Refer to HV, B+ and Shutdown adjustment procedures
described in the appropriate schematic and
diagrams(where used).
AC VOLT METER
0.15 µF
1500 OHM
10 WATT
Good earth ground
such as a water
pipe, conduit, etc.
FIG 1
Place thes probe
on each exposed
metallic part

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SUBJECT : IMPLOSION
1.All direct viewed picture tubes are equipped with an
integral Implosion protection system, but care should be
taken to avoid damage during installation.
Avoid scratching the tube. If scratched, replace it.
2. Use only recommended factory replacement tubes.
SUBJECT : TIPS ON PROPER INSTALLATION
1.Never install any receiver in closed-in recess, cubbyhole or
Closely fitting shelf space over, or close to heat duct, or in
the path of heated air flow.
2.Avoid conditions of high humidity such as : Outdoor patio
Installations where dew is a factor. Near steam radiators
where steam leakage is a factor, etc.
3.Avoid placement where draperies may obstruct rear
venting. The customer should also avoid the use of
decorative scarves or other coverings which might obstruct
ventilation.
4.Wall and shelf mounted installations using a commercial
mounting kit, must follow the factory approved mounting
instructions. A receiver mounted to a shelf or platform
must retain its original feet(or the equivalent thickness in
spacers) to provide adequate are flow across the bottom,
bolts or screws used for fasteners must not touch and
parts or wiring. Perform leakage test on customized
installations.
5.Caution customers against the mounting of a receiver on
sloping shelf or a tilted position, unless the receiver is
properly secured.
6.A receiver on a roll-about cart should be stable on its
mounting to the cart. Caution the customer on the hazards
of trying to roll a cart with small casters across thresholds
or deep pile carpets.
7.Caution customers against the use of a cart or stand which
has not been listed by underwriters laboratories, inc. For
use with their specific model of television receiver or
generically approved for use with T.V.’ s of the same or
larger screen size.

2. Specification
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Power Requirement AC 120V, 60Hz
Power Consumption 210watts
General Dimensions(W/H/D) 41”W x 26.2”H x 24.6”D
Weight 81Kg (178.61bs)
Antenna One 75ohm external input terminal for
UHF/VHF/Cable
Screen Size 34”(diagonal), 16:9 Aspect Ratio
Picture Display Format DTV : 1080I @ 33.75KHz
NTSC/DVD : 480p @ 31.5KHz
Horizontal Resolution 800 Lines
Sound System Dolby Pro Logic
Sound NTSC Audio Multi CH TV Stereo(MTS) /
Second Audio Program(SAP)
Audio Power 8W/ch (Main L/R), 5W/ch (Center)
Rear
RF Antenna Input
NTSC A/V In 2each (Video/L/R)
1each (S-Video/Video/L/R)
NTSC A/V Monitor Out 1each (Video/L/R)
Inputs/ HD Component In 1each (Y/Pb/Pr)
Output DVD Component In 1each (Y/Cb/Cr)
Surround Channel Out 1each (SL/SR)
Sub woofer Out 1each
Side
NTSC A/V In 1each (S-Video/Video/L/R)
Headphone 1each (L/R)

3. Remote control overview
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The remote control has the following functions:
Power button
Press to turn the HDTV Monitor (and other equipment) on and off
DTV button
Press this button repeatedly to display HD Component Video.
TV/VIDEO button
Press to view components you have connected to the HDTV Monitor.
Press this button repeatedly to display:
*TV mode
*Video1
*Video2
*Video3
*DVD
VCR Control Board
Basic VCR functions are operated with buttons on this board.
Direct Channel Selection Board
Pressing the numbers on this board, you can select program channels of
the screen directly.
Mode buttons
Press to select which equipment you wish your remote control to
operate:
*TV
*CATV (cable box)
*VCR
Menu button
You can adjust the picture, sound and many other functions.
Volume buttons
Press to raise and lower the volume on your HDTV Monitor.
Channel buttons
Press to select channels.
Mute button
Press to mute the HDTV Monitor sound.
PIP Search buttons
Simultaneous window selection is possible through buttons of this board,
and various layouts of the windows can be selected according to the
user’s need or desire.
TV/CATV button
This button is used to convert reception modes between aerial and
cable transmission systems.
STILL button
Press to pause the screen temporarily.
WIDE button
Press to convert the screen aspect ratio between 4:3 and 16:9 and vice
versa.
ADD/ERASE button
Press to operate channel memory functions.
SLEEP button
Press to operate set up time memory for an automatic turn off.
Surround button
Press to choose one of the “Pro Logic” modes.

4. Limited Warranty
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Daewoo Electronics Corporation of America Inc. (also known as DECA) warrants this product to be free from defects in
material and workmanship and agrees to remedy any such defect.
This warranty covers 3 years labor and 3 years parts from the date of original purchase.
This warranty applies only to product purchased from authorized DECA dealer and used within the boundaries of U.S.A.
This warranty does not apply to product that has been improperly installed, subjected to usage for which the product was
not designed, misused or abused, damaged during transportation, or which has been altered in any way that affects the
reliability or detracts from its performance.
How you get warranty service
Warranty service can only be provided by an authorized DECA service center. For the closest authorized service center
to you, please contact your Dealer. In order to receive warranty service you must provide the authorized service center
with a copy of proof of purchase, signifying the date of purchase and the name of the Dealer from whom you purchased
the product.
Statutory warranties
The purchase may have rights under existing provincial or federal laws, and where any terms of this warranty are
prohibited by such laws, they are deemed null and void, but the remainder of the warranty shall remain in effect.
If you require further assistance, please call:
1-800-DAEWOO-8

5. Service Modes
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1.Entering to Service Mode
With the service remote control
2. Function of each service mode
1) S1 : Heat Run mode.
2) S2 : Screen Voltage Control mode
The vertical deflection is down, and a horizontal line appears on the screen.
3) S3 : Sound Controls mode
4) S4 : Video Controls mode
5) S5 : Picture Quality Controls Mode : Fixed Data
S1 : Heat Run S2 : Screen Voltage S3 : Sound Controls
S4 : Video Controls S5 : Picture Quality S6 : Geometry S7 : PIP
S8 : White Balance
Auto power on mode Exit
S9 : Sub Picture & Sub Audio S10 : Option S12 : Factory Setting
Full white mode
•Equalizer : 60Hz, 250Hz, 1KHz, 3.5KHz, 10KHz
•Main Volume : 0 63 31
•Balance control : -31 31 0
•Center Volume : 0 63 31
•Tint : 0 63 31
•Brightness : 0 48 24
•Contrast : 0 48 24
•Color : 0 63 31
•Sharpness : 0 63 31
LIM 1
SYS 3
AGI 0
DCO 1
CLP 0
CLM 0
ABM 0
ABT 3
HSE 0
•Don’t adjust above the mode, these are to adjust data of RGB Video Process IC (CXA2101).
FIX 0
VTC 0
HWI 0
HDT 0
HSM 0
CTI 3
LRG 15
GAM 15
PAB 0
BLK 0
SHP 3
PRE 3
LTI 0
VML 2
VMD 0
DCT 2
DPI 2
AKB 0

Service Modes
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6) S6 : Geometry Adjustment mode
NTSC/DVD
After receiving Air or external video, adjust geometry.
DTV
After connecting HD component at the DTV Input, adjust geometry.
7) S7: PIP Adjustment
•Press “PIP” button twice until the screen becomes two windows.
•Adjust below items so that the picture qualities of sub screen may be just the same with the main screen.
8) S8: White Balance Adjustment mode
9) S9 : Sub picture quality & Sub audio adjustment mode
HDUTY H Duty 16
HPOSI H Position 60
SPINW Side Pin W 24
SPIN Pincusion 48
HSIZE H Size 42
VSIZE V Size 73
VPOSI V Position 62
VSLIN V S Linearity 31
VCLIN V C Linearity 23
TRAPE Trapezoid 29
SPINS Side Pin S 33
FOCUSPH H Focus Phase 32
FOCUSPA H Focus Amplitude 32
MOIRE 16
VSMAX V Size Max 31
HPOSI H Position 67
HSIZE H Size 40
VSIZE V Size 63
VPOSI V Position 97
Brightness +16
Contrast 48
Sharpness 64
Tint +0
RDRV Drive R 31
GDRV Drive G 31
BDRV Drive B 31
RCUT Cut off R 64
GCUT Cut off G 64
BCUT Cut off B 64
SUB-CONT 15 Sub Contrast available
SUB-BRIG 1 Sub Brightness available
SUB-SHP 3 Sub Sharpness available
SUB-COR 15 Sub Color available
SUB-TINT 15 Sub Tint available
PRE-FM 56 RF Audio Level Don’t adjust
PRE-SCART 25 Don’t adjust
PRE-SCART 1 38 Don’t adjust
NOR HP 20 The horizontal position of OSD available
DTV HP 10 The horizontal position of DTV OSD available
STEREO ID 32 Stereo detection sensitivity Don’t adjust
RF P-MUTE 3 When channel UP/DN, Video mute time available

Service Modes
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10) S10 : Option Adjustment mode
11) S12 : Factory Setting
3. Selecting the adjusting items
Pressing of Channel button changes the adjustment items. ( button for reverse order)
4. Adjusting the data
Pressing of VOLUME button changes the value of data. ( button for reverse order)
5. Exit from Service Mode
Press again to make service mode exit.
Caption English Fixed
CALMP 10 Don’t adjust
OSD POS 15 The horizontal position of Caption OSD available
EPOS 15
V POS 144 The Vertical position of Caption OSD available
POTION America / Korea Fixed
PC INPUT off Fixed
CIP-CT 27 The horizontal PLL speed of Video Process IC (VPC3230) Don’t adjust
CIP-BR 27 Don’t adjust
CIP-CR 22 Don’t adjust
CIP-CB 0 Don’t adjust
Dolby Ext off Dolby External L/R Mode Don’t adjust
CH 2
TV/VIDEO TV
TV/CABLE TV
Volume 20
Center Volume 0
PIP OFF
Equalizer Center
Auto Picture Standard
Auto Sound User
Wide 16:9
Zoom 16:9
Caption OFF
Child Lock OFF

6. General Adjustment
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In the majority of cases, a high definition digital television will need basic adjustments such as high voltage, screen
voltage, focus, white balance, sub brightness, and geometry. All adjustments should be performed after heat-running the
set for at least 20 minutes.
1. Press the S1 button on the service remote control, and then full white pattern will appear on the screen.
2. Press the S1 button twice, and then the pattern will disappear.
High Voltage Adjustment
1. Operate the set for at least 20 minutes.
2. Connect the probe of high voltage meter to CRT ANODE.
3. Adjust the variable register RV801 on the power assembly so that high voltage may be to be between
31.5KV ~ 32.5KV.
Screen Voltage Adjustment
1. Press the S2 button on the service remote control.
Vertical deflection will be down, and a horizontal line will appear on the screen.
2. Turn the variable screen volume of FBT to adjust screen voltage, at the point that a horizontal line only just appears.
Focus Adjustment
1. Tune on RETMA pattern.
2. Turn the variable focus volume of FBT so that the center area of screen is sharp scanning line.
3. Turn the variable volume R522 on the CRT assembly so that the edge of screen may be sharp scanning line.
White Balance Adjustment
1. Input the Black & white signal to the HD Component jack on the rear panel.
<Black & White Pattern>
2. The color temperature is the following.
•x=0.270 0.005 y=0.270 0.005
•Color temperature : 13,214°K
3. Light Area Adjustment
1) Press S8 button.
2) On the center of light area, attach the sensor of a white balance meter.
3) To be Y=100, turn the Light Beam control volume on the White & Black pattern generator.
4) To adjust the white balance of light area, select Drive R, G, B with CHANNEL Up or Down buttons, and adjust
individual values with VOLUME Up or Down buttons.
4. Dark Area Adjustment
1) On the center of dark area, attach the sensor of a white balance meter.
2) To be Y=15, turn the Dark Beam control volume on the White & Black pattern generator.
3) To adjust the white balance of dark area, select Bias R, G, B with CHANNEL Up or Down buttons, and adjust
individual values with VOLUME Up or Down buttons.
4) Repeat two processes above until the white balance is completed.
Dark Area Check
Light Area Check

General Adjustment
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Sub Brightness Adjustment
1. Tune on RETMA Pattern.
2. Press S9 button.
3. The following OSD menu will appear on the screen, and the data are initial values before adjusting.
4. To be between Step 10% and 20% on the Contrast Chart, perform fine adjustment of sub brightness.
SUB-CONT 15
SUB-BRIG 1
SUB-SHP 3
SUB-COR 15
SUB-TINT 15
PRE-FM 56
PRE-SCART 25
PRE-SCART1 38
NOR HP 20
DTV HP 10
STEREO ID 32
RF P-MUTE 3
40% 30% 20% 10%
50% 0% 0% 5%
60% 70% 80% 100%

General Adjustment
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Geometry
1. To adjust V-Position, H-Size, H-Position and so forth, tune on RETMA Pattern.
2. To adjust Pincushion, Trapezoid and so forth, tune on Cross Hatch signal.
3. Screen Mode should be on 16:9 mode, and the Video Mode should be on Normal mode.
4. Press S6 button to adjust Geometry.
Item Screen Image Adjustmant Procedure
1) Receive NTSC RETMA signal.
2) The Screen mode should be selected on 16:9
mode
V Size Max. 3) Adjust Vertical Size so that over scanning rate may
be 105%.
4) Check if the center circle is not only circular on 16:9
mode but also on 4:3 mode.
Over Scanning Rate: 105%
1) There is no need to adjust.
2) Check if the value of data is “0”.
Vertical
Size
1) Receive NTSC RETMA signal.
2) The Screen mode should be selected
on 16:9 mode.
Vertical Adjust Vertical Position so that the circle of
Position RETMA signal may be centered in the vertical
direction.
1) Receive NTSC RETMA signal.
2) The Screen mode should be selected
V C Linearity on 16:9 mode.
3) When the center area of RETMA signal’s circle is
C type in the vertical direction, adjust VC
Linearity so that vertical interval may be the same.

Item Screen Image Adjustmant Procedure
1) Receive NTSC RETMA signal.
2) The Screen mode should be selected on 16:9
V S Linearity mode.
3) When the center area of RETMA signal’s circle is
S type in the vertical direction, adjust VS
Linearity so that vertical interval may be the
same.
1) Receive NTSC RETMA signal.
2) The Screen mode should be selected on 16:9
mode
Adjust Horizontal Size for over scanning rate
Horizontal Size 106%. Check if the center circle of RETMA signal
is circle on Normal mode.
1) Receive NTSC RETMA signal.
2) The Screen mode should be selected on 16:9 mode
Horizontal 3) Adjust Horizontal Position so that the circle of
Position RETMA signal may be centered in the horizontal
direction.
1) Receive NTSC Cross Hatch signal.
2) The Screen mode should be selected on 16:9
mode.
Pincushion 3) When the vertical lines of the left and right side
are distorted such as the left figure, adjust
Pincushion so that the vertical lines may be
straight.
1) Receive NTSC Cross Hatch signal.
2) The Screen mode should be selected on 16:9
mode.
Side Pin W 3) When the vertical lines of the left and right side
are not straight but distorted in the W type, adjust
Side Pin W to correct the unbalanced vertical
lines.
1) Receive NTSC Cross Hatch signal.
2) The Screen mode should be selected on 16:9
Side Pin S mode.
3) When vertical lines of the left and right side is not
straight but distorted in the S type, adjust Side Pin
S to correct the unbalanced vertical lines.
General Adjustment
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General Adjustment
- 14 -
Item Screen Image Adjustmant Procedure
1) Receive NTSC Cross Hatch signal.
2) The Screen mode should be selected on 16:9
mode.
Trapezoid 3) When the screen shape is not rectangular but
trapezoid, adjust Trapezoid to correct the
unbalanced shape.
1) There is no need to adjust.
H Duty 2) Check if the value of data is “16”.
1) There is no need to adjust, and check if the value
of data is “32”.
H Focus Phase 2) Check that the focus on the right and left side is
clear.
1) There is no need to adjust, and check if the value
H Focus of data is “32”.
Amplitude 2) Check if the focus on the right and left side is clear.
400Vp-p
900Vp-p
60Hz
400Vp-p
900Vp-p
60Hz

7. Special Adjustment (When replacing new circuit boards)
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1. Power assembly
1) After replacing a new assembly, X Radiation Protection Circuit Test
When service has been performed on the horizontal deflection system, high voltage system or B+ system, the
X-Radiation Protection Circuit Test must be tested for proper operation as follows:
1-1) Operate the HDTV Monitor for at least 20 minutes.
1-2) Perform this test at the normal video and sound.
1-3) Check the cathode voltage of D837. Its voltage should be about 25VDC.
1-4) Connect a resister 24K(1/4W) with parallel to R873.
1-5) Then the set will be shut down, lighting up red to the power indicator.
1-6) If it is not, the circuit of X-Radiation Protection must be repaired before the set is returned to the
customer.
2) The rest adjustment idem are no need to adjust.
2. Main assembly
1) After replacing a new assembly, the rest adjustments are no need.
3. Video assembly
1) No need to adjust.

8. Troubleshooting charts
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No Picture
(NTSC Signal)
OSD is on the screen.
NO
Check OSD signal of I701.
R/G/B OSD : #64, 63, and 62
BL OSD : #61
Check OSD signal of UC107.
R/G/B OSD : #50, 51, and 52
BL OSD : #49
Check video signal of IA1.
Video1 :CVBS to #43, Y to #45,
and C to #47
Video2 :CVBS to #1
Video3 :CVBS to #7, Y to #9,
and C to #11
Check each
input signal.
When CVBS input, CVBS is to #34 of IA1.
When Y/C input, Y/C is to #37 and #39 of IA1.
When CVBS input, CVBS is to #88 of UC100.
Y/C signal of 3D comb filter is to #84 and #83 of UC100.
When Y/C input, Y/C is to #88 and #96 of UC100.
Y/C signal is to #73 and #71 of IC UC104.
Check below signal of UC104
-Y and C signal : #73, #71
-Picture Bus Y(MY0~MY7)
-Picture Bus C (MC0~MC7)
-V sync pulse (VSM) : #57
-Active video output (AVO) : #54
-Clock out (LLC2) : #27
Check below signal of UC106
-Picture Bus Y(MY0~MY7)
-Picture Bus C (MC0~MC7)
-V sync pulse (VSM) : #26
-Active video output (AVO) : #27
-Clock out (LLC2) : #18
-Y /Cb /Cr out: #87, 84, and 90
-H/V sync : #4, 5
Check below signal of UC107
R/G/B out : #35, 37, and 39
Check TV video signal of IA1.
CVBS of main tuner (TU01) : #41
CVBS of sub tuner (TU02) : #27
Check DVD signal to UC104.
Y/Cb/Cr : #5, 4, and 3
Check Tuner
(TU01 & TU02).
No Picture
(DVD Signal)
Check below signal of UC107
Y/Cb/Cr in : #69, 68 and 67
H/V sync : #66, 65
No Picture
(DTV Signal)
Check DTV signal of UC107
Y/Pb/Pr in : #5, 4 and 3
OSD
OSD
NO
END
AV Signal RF Signal

Troubleshooting charts
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No Sound
(NTSC Signal)
Check audio signal of IA1.
Video1 : L to #44, R to #46
Video2 : L to #2, R to #4
Video3 : L to #8, R to #10
AV Signal RF Signal
Check the audio base-band signal to SIF of TU01.
Check audio signal of UC102.
-SIF to #67 -RF main L/R to #36, 37
Check audio signal of IA1.
-RF main L/R to #9, 11
-RF sub Mono to #25, 26
Check audio signal of IA1.
-Main L/R to #33, 32
-Sub L/R to #18, 16 (for the sub picture of PIP)
Check audio signal of UC102.
-Main L/R to #47, 48
(for RF and external audio 1,2,3)
-Sub L/R to #56, 57 (for Headphone L/R out) Check DTV L/R of UC102.
-L/R to #53, 54
No Sound
(DTV Signal)
Check L/R out of UC102.
L/R/C to #28, and 27
Check C out of UC103
C to #34
Check SL/SR/Woofer out of UC102.
SL/SR/W to #25, 24, and 27
Check Headphone L/R out of UC102.
L/R to #34 and 33
Check the volume control of
headphone to IA4.
Check audio Amp (I601).
L/R/C In to #1, 2, and 4
L/R/C Out to #12, 11, and 8
Check DVDL/R of UC102.
-L/R to #50, 51
No Sound
(DVD Signal)
END
Check Headphone L/R out of IA03
L/R to #7 and 1

Troubleshooting charts
- 18 -
No Raster
NO
I701 communicates with I402 on the IIC bus.
Check the #3 (SDA) and #4 (SCL) of I402.
5Vp-p
Check I701
and I402.
Vertical
Deflection
Check #17 (H-Drive output) of I402.
0.7Vp-p
31.5KHz (NTSC/DVD)
33.75KHz (DTV)
Horizontal
Deflection High Voltage
Drive
Check H Drive signal to emitter of Q411.
12Vp-p
31.5KHz (NTSC/DVD)
33.75KHz (DTV) Check
Q416, Q417
H Drive signal is output to pin 3 of I407.
12Vp-p
33.75KHz
Check # 9
(E/W ) of
IC402.
NO
H/D1
Trigger pulse is input to #2 of I407.
31.5KHz (NTSC/DVD)
33.75KHz (DTV)
2Vp-p
6Vp-p
The control voltage of H Drive is
input to #5 of I407.
60Hz
0.5Vp-p
7Vp-p
NO
NO

Troubleshooting charts
- 19 -
H/D1
60Hz
5Vp-p
90V
Horizontal Drive B+ to R481 is 90V 5Vp-p
If the impedance value of Q425's collector
is near zero Ω, the horizontal deflection TR
(Q425) is dead. Replace Q425.
NO
END
Check 200VA to PA14M. To No Power
NO
H Drive signal is output to Source of Q423.
200Vp-p
31.5 / 33.75KHz
The voltage waveform of Q425's
Collector is the following.
1,300 50Vp-p
High Voltage Drive
Check H Drive signal to emitter of Q402.
12Vp-p
33.75KHz
Check I403
and high
voltage
feedback
circuits.
NO
HVD1
Check pin 17 (H-Drive output) of I402.
0.7Vp-p
31.5 / 33.75KHz
Check I402
Trigger pulse is input to pin 2 of I401.
31.5 / 33.75KHz
2Vp-p
6Vp-p
60Hz
0.25Vp-p
7Vp-p
The control voltage of high voltage
feedback is input to #5 of I401
NO