AOC L42W761 User manual

42’’ LCD TV AOC L42W761
1
Service
Service
Service
Horizontal Frequency
31~60kHz
TABLE OF CONTENTS
Description Page Description Page
SAFETY NOTICE
ANY PERSON ATTEMPTING TO SERVICE THIS CHASSIS MUST FAMILIARIZE HIMSELF WITH THE
CHASSIS AND BE AWARE OF THE NECESSARY SAFETY PRECAUTIONS TO BE USED WHEN SERVICING
ELECTRONIC EQUIPMENT CONTAINING HIGH VOLTAGES.
CAUTION: USE A SEPARATE ISOLATION TRANSFOMER FOR THIS UNIT WHEN SERVICING
R FOR TH
UNIT WHEN S
6.3.IR Board………………………………………….......33
6.4.Connector Board……………………..……….......34
6.5.Key Board……………………………….……….......34
7. White-Balance, Luminance Adjustment...................35
8 Block Diagram.……...........................................37
9. Schematic……………...…….……..………………..38
9.1 Main Board…….………..….…………….….......38
9.2. Power Board…………….……….………….......54
9.3. IR Board…………….……….………….…….......55
9.4. Key Board…………….……….………….......56
9.5. Side Board…………….……….……….…….......57
9.6. Audio Board…………………………………………58
10. Exploded View..…......................................59
11. BOM List……………….…………………………….60
Table Of Contents.......……..............................…........1
Important Safety Notice.......................................……......2
Revision List.…........................................……......3
1. General Specification..............................………........4
2. Operating Instructions…………………….……….......5
2.1. The Use Of Remote Control…….………….…….......5
2.2. To Use The Menus...…………………….……….......6
2.3. How To Connect…….…………………….……….....13
2.4. Front Panel Control Knobs……………….……….....15
3. Input/Output Specification…………....................…....16
4. Mechanical Instructions…………………….................18
5. Repair Flow Chart ……………………….…….…….....23
6. PCB Layout ………………..………………....….......28
6.1.Main Board…………..………………….……….......28
6.2.Power Board……………..………….……….......30

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Important Safety Notice
Proper service and repair is important to the safe, reliable operation of all AOC Company Equipment. The service
procedures recommended by AOC and described in this service manual are effective methods of performing service
operations. Some of these service operations require the use of tools specially designed for the purpose. The
special tools should be used when and as recommended.
It is important to note that this manual contains various CAUTIONS and NOTICES which should be carefully read in
order to minimize the risk of personal injury to service personnel. The possibility exists that improper service
methods may damage the equipment. It is also important to understand that these CAUTIONS and NOTICES ARE
NOT EXHAUSTIVE. AOC could not possibly know, evaluate and advise the service trade of all conceivable ways in
which service might be done or of the possible hazardous consequences of each way. Consequently, AOC has not
undertaken any such broad evaluation. Accordingly, a servicer who uses a service procedure or tool which is not
recommended by AOC must first satisfy himself thoroughly that neither his safety nor the safe operation of the
equipment will be jeopardized by the service method selected.
Hereafter throughout this manual, AOC Company will be referred to as AOC.
WARNING
Use of substitute replacement parts, which do not have the same, specified safety characteristics might create
shock, fire, or other hazards.
Under no circumstances should the original design be modified or altered without written permission from AOC.
AOC assumes no liability, express or implied, arising out of any unauthorized modification of design.
Servicer assumes all liability.
FOR PRODUCTS CONTAINING LASER:
DANGER-Invisible laser radiations when open AVOID DIRECT EXPOSURE TO BEAM.
CAUTION-Use of controls or adjustments or performance of procedures other than those specified herein may
result in hazardous radiation exposure.
CAUTION -The use of optical instruments with this product will increase eye hazard.
TO ENSURE THE CONTINUED RELIABILITY OF THIS PRODUCT, USE ONLY ORIGINAL MANUFACTURER'S
REPLACEMENT PARTS, WHICH ARE LISTED WITH THEIR PART NUMBERS IN THE PARTS LIST SECTION OF
THIS SERVICE MANUAL.
Take care during handling the LCD module with backlight unit
-Must mount the module using mounting holes arranged in four corners.
-Do not press on the panel, edge of the frame strongly or electric shock as this will result in damage to the screen.
-Do not scratch or press on the panel with any sharp objects, such as pencil or pen as this may result in damage to
the panel.
-Protect the module from the ESD as it may damage the electronic circuit (C-MOS).
-Make certain that treatment person’s body is grounded through wristband.
-Do not leave the module in high temperature and in areas of high humidity for a long time.
-Avoid contact with water as it may a short circuit within the module.
-If the surface of panel becomes dirty, please wipe it off with a soft material. (Cleaning with a dirty or rough cloth may
damage the panel.)

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Revision List
Version
Release Date
Revision Instructions
TPV Model
A00
July-20-2007
Initial Release
E427AZNK2WE1NN

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1. General Specification
Items
Specification
LCD Panel
Panel Type
T420XW01 V500 TW AUO
Driving system
TFT-LCD AUO Panel
Aspect Ratio
16: 9
Resolutions
1366 x768
Active Area
930.25 (H) x 523.01(V)
Pixel Pitch
0.681 mm (H) X 0.681 mm(V)
Display colors
16.7 million
Panel Typical Brightness:
500 cd/㎡
Panel Typical Contrast：
1500:1
Color Temperature
Cool / Warm/normal
Input
H-Frequency
31KHz to 60KHz
V-Frequency
50Hz to 75 Hz
TV Function
TV Standard
NTSC/M
Color systems
NTSC
Video Inputs
AV
RCA x 1
Audio L/R x 1
S-Video
Y ,C x 1
Audio L/R x 1
COMPONENT
Y, Pr/Cr, Pb/Cb x 1
Audio channel L / Rx 1
AUDIO
Headphone Mini-jack for stereo (3.5ø)
HDMI INPUT:
Suggested scan rates: 1080i, 720p, 480p, 480i
OSD language
English. French. Spanish
Wall Mount
VESA 400 x 200 mm
Weight
24.5 kg
Dimensions
(Include Stand)
1050 mm(W) x 767 mm(H) x 290mm(L)
Power
Power Supply
AC100V~240V, 50/60Hz
Power Consumption
≤250W
Environment
Operating Temperature
+ 0 °C ~ + 40 °C
Storage Temperature
-10 °C ~ + 50 °C
Operating
10% ~ 85%
Supplied Accessories:
1pcs Power cord, 1pcs Remote control(with two AA alkaline batteries), 1pcs User
manual, 1pcs Signal cable, 1pcs Pc Audio cable
NOTE: This TV set does not provide HD video Output.

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2. Operating Instructions
2.1. The Use of Remote Control
2.2 To Use the Menus

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SETUP MENU
VIDEO MENU
1. Press the MENU button to display the main menu
2. Use the cursor up/down to select a menu item.
3. Use the cursor left/right to enter a submenu.
4. Press the OK button to enable/disable the function.
5. Press the MENU or EXIT button to exit the menu. Press the MENU button to enter the main OSD (On Screen
Display). Adjust the items including Setup menu, Video menu, Audio menu and Feature menu. However, some
function items in the menus may only be enabled in the particular source modes.
The Setup menu in TV mode shows as below. In others source modes, the Setup menu only shows Menu
Language and Aspect Ratio items.
1. Tuning Band: Select TV source signal from the Air (antenna) or Cable (CATV).
2. DTV Signal: Show the intensity of the received DTV signal.
3. Auto Ch Search: Automatically scan all NTSC / ATSC TV channels and then store in the channel table. In
channel scan process, the OSD can display the number of channels which had been found.
4. Add on Ch search: Add channels which are new found.
5. Manual Channel Set: Show the channel setup table. User can choose to display the ATSC or NTSC TV channels
and then edit (add/delete) the channel numbers.
6.Channel Labels: Show the NTSC or ATSC TV channel label menu for user modifying channel labels specifically.
7. Menu Language: Select the menu display language. (English /Spanish /French)
8. Aspect Ratio: Select the display aspect ratio. (Normal / Zoom / Wide / Cinema)
9. Favorite Channel Mode: when favorite channel mode on user can edit favorite channel table in favorite channel
set option.

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AUDIO MENU
The Video menu in most source modes shows as below. It provides several video adjustment items for user fine
tuning the video display. Only in VGA source modes, the Video menu simply provides Contrast, Brightness, Back
light and Settings (Preset) items.
1. Contrast: Video contrast adjustment, the tuning range is 0 ~ 100.
2. Brightness: Video brightness adjustment, the tuning range is 0 ~ 100.
3. Sharpness: Video sharpness adjustment, the tuning range is -50 ~ 50.
4. Color: Video color chroma adjustment, the tuning range is 0 ~ 100.
5. Tint: Video tint adjustment, the tuning range is R50 ~ G50.
7. Settings: Restore the default video settings.
English
The Audio menu in TV mode shows as below. It provides audio adjustment for user to modify the audio setting.
Except in ATSC TV mode, some audio adjustment items for user to modify the audio setting. Excepting in ATSC TV
mode, the Audio Language option is disable in others source modes. The audio language setting is only available
in ATSC TV source. Furthermore, the Bass and Treble tuning items are only enabled while the SRS option set “Off”
(tune-off the SRS sound effect). The Default states of Bass and Treble items are enabled as well as SRS option set
“Off”.
1. Audio Language: Change the audio language setting on ATSC TV programs. The number of the supported
audio languages depends on the ATSC TV programs.
2. Bass: Bass tone adjustment, the tuning range is 0 ~ 63. (The default state is enabled)
3. Treble: Treble tone adjustment, the tuning range is 0 ~ 63. (The default state is enabled)
4. Balance: Audio balance adjustment, the tuning range is L31 ~ R31.
5. Digital Audio Output: Digital audio output format selection, user can choose RAW (default) or PCM format.
6. SRS: Choose to turn on / off the SRS sound effect. The default value is Off.
7. TV Speaker: Choose to turn on / off the TV internal speaker. The digital audio output signals、earphone output

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FEATURE MENU
signals and the composite L/R audio output signals will not be turn-off even though the TV speaker is off. The default
setting is On.
8. Settings: Restore the default audio settings.
The Feature menu in TV mode shows as below. It provides certain optional control functions such as time set, sleep
timer, video noise reduction, parental control (V-chip) and close caption style setting. This menu gives users the
most flexibilities to satisfy their generally demands. According to the various requirements in different source modes,
certain features should be hidden (disable) on the menu. The details footnotes will be described clearly below.
1. Time Set: Set current time. This sub-menu includes Time Zone and Time items.【Time Zone】item provides user
to set current time zone, such as: Pacific、Alaska、Hawaii、Eastern、Central and Mountain. 【Time】item provides
user to set the time clock.
2. Sleep Timer: Enable or disable the TV standby timer. User can set the TV standby timer as off / 5 min / 10 min /
15 min / 30 min / 45 min / 60 min / 90 min /120 min / 180 min / 240 min. Timer starts to count down after cursor
leaving the sub-menu. (At the moment, the item shows 『** min Left』and the cursor highlights on the Feature icon.)
3. Advanced Video Menu: Provide the Noise Reduction setting 、Color Temperature and 3D Y/C filter options
for enhancing video quality.
【Noise Reduction】gives four NR effect degrees, such as: Low、Mid、High and Off. The default setting is off.
【3D Y/C】provides On / Off switches. The default setting is On.
【Color Temp】gives three color temperature modes as: Normal、Warm and Cool. The default mode is Warm.
【Setting】restores the default advanced video option settings.

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4. Password Set: Change the 4-numeral parental control password. Three steps are required for changing the
password: Enter Old Password -> Enter New Password -> Confirm New Password. Note: This item is only available
in TV, Composite and S-Video source modes. The default password is 『0 0 0 0』.
5. Parental Control: provide the parental Control (V-chip) function setting. Before entering the Parental Control
sub-menu, user has to key in the password first. Then enter the Parental Lock item, User can modify the restricted
table about MPAA or TV Rating respectively. While exiting the sub-menu, the parental control function is working.
The inhibitive channels or source signals can be un-lock through pressing the V-CHIP key on the remote control and
then key in the correct password. Note: This feature is only available in TV, Composite and S-Video source modes.
(The default password is: 0 0 0 0.)

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6. Digital Captions: Select the close caption options ( Service 1-6, Text 1-4 and CC 1-4) in digital TV mode. When
select service 1 to service 6 you can modulate parameters in the Digital Close Caption.
7. Digital Closed Caption: Provide numerous options for setting the close caption style. In the sub-menu. 【Style】
item can be set as Automatic or Custom mode. If Custom mode is selected, user can modify the detail styles
described below. The setting result will be shown immediately on the bottom side of the sub-menu OSD. Note: This
feature is only available in Digital TV (ATSC) mode.
【Size】: Digital close caption font size, which can be set as Small、Normal or Large.
【Font】: Digital close caption font style, which can be chosen as Default or Font 1 ~ 7.
【Text Color】: Giving Red / Green / Blue / Yellow / Magenta / Cyan / Black / White Colors.
【Text Opacity】: Giving Transparent / Translucent / Solid / Flashing modes.
【Background Color】: Giving Red / Green / Blue / Yellow / Magenta / Cyan / Black / White Colors.
【Background Opacity】: Giving Transparent / Translucent / Solid / Flashing modes.

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【Edge Effect】: The text edge effects, which gives None / Raised / Depressed / Uniform / Left Shadow / Right Shadow modes.
【Edge Color】: The colors of text edge effects, which provides Red / Green / Blue / Yellow / Magenta / Cyan / Black / White
Colors.
8. Component Set: This option only shows and is available in component mode, which provides fine tuning component display,
such as: 【H-Position】、【V-Position】and【Phase】. All these items are giving the tuning range from 0 to 100.【Setting】item
provides the default component setting values restoring.
9. VGA Set: This option only shows and is available in VGA mode, which provides fine tuning VGA display, such as :
【H-Position】、【V-Position】、【Clock】and【Phase】. All these items are giving the tuning range from 0 to 100.【Setting】
item provides the default VGA setting values restoring.
Care of the screen
Do not rub or strike the screen with anything hard as this may scratch, mar, or damage the screen permanently.
Unplug the power cord before cleaning the screen. Dust the TV by wiping the screen and the cabinet with a soft,
clean cloth. If the screen requires additional cleaning, use a clean, damp cloth. Do not use liquid cleaners or aerosol
cleaners.
Mobile telephone warning
To avoid disturbances in picture and sound, malfunctioning of your TV or even damage to the TV, keep away your
mobile telephone from the TV.
End of life directives
We are paying a lot of attention to produce environmentally friendly in green focal areas. Your new receiver contains
materials, which can be recycled and reused. At the end of its life specialized companies can dismantle the
discarded receiver to concentrate the reusable materials and to minimize the amount of materials to
be disposed of. Please ensure you dispose of your old receiver according to local regulations.
Regulatory Notices –Federal Communications Commission Notice
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15
of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed
and used in accordance with the instructions, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful
interference to radio or television reception, which can be determined by turning the equipment off and on, the user
is encouraged to try to correct the interference by one or more of the following measures:
1.Reorient or relocate the receiving antenna.

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2.Increase the separation between the equipment and the TV.
3.Connect the equipment into wall power outlet on a circuit different from that to which the receiver is connected.
4.Consult the dealer or an experienced radio or television technician for help.
Modifications –
The FCC requires the user to be notified that any changes or modifications made to this device that are not
expressly approved by Norcent Technology Inc. may void the user’s authority to operate the equipment.
Cables –
Connections to this device must be made with shielded cables with metallic RF/EMI connector hoods to maintain
compliance with FCC Rules and Regulations.
Canadian notice –
This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment
Regulations.

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2.3 How to Connect
There are several ways to connect your TV. Please use the following chart to determine which connection is best
for you.
Once your equipment is connected, use the following procedure to view the input signal:
Press the source button on the remote controller to select the relevant source to view. (ex: Press VIDEO button to
select “Video1 Composite Rear” if you have connected a DVD player to Video1 Composite socket.) "HDMI, the
HDMI logo and High-Definition Multimedia Interface are trademarks or registered trademarks of HDMI Licensing
LLC."

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Note: The MUTE key on the remote control works on both TV internal speaker and the earphone output.

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2.4 Front Panel Control Knobs

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3. Input/Output Specification
3.1 RGB Signal input
15 - Pin Color Display Signal Cable
Pin No.
Description
Pin No.
Description
1
Red Video
9
Mandatory +5V Supply for PC Bypass
2
Green Video
10
Sync Ground
3
Blue Video
11
SDA(Remote Control)
4
SCL(Remote Control)
12
Bi-directional Data (SDA) for PC Bypass
5
Ground
13
H-Sync.
6
Red Video Ground
14
V-Sync.
7
Green Video Ground
15
Data Clock (SCL) for PC Bypass
8
Blue Video Ground
3.2 AV/S-Video/Component signal input
AV (Composite Video input)
Video1 / Video2
System
NTSC
Amplitude
1.0 V(p-p), negative sync.
Impedance
75 ohm terminated
S-Video (Y / C input)
S-Video1 / S-Video2
System
NTSC
Y signal amplitude
1.0Vpp (including sync)
C signal amplitude
0.286Vpp
Impedance
75 ohm terminated
Component (Y, Pb/Cb, Pr/Cr input)
Component1/Component2
System
1080i, 480p, 720p, 480i
Y signal amplitude
1.0Vpp (including sync)
Cr, (R-Y) / Cb, (B-Y)
Signal amplitude
±0.35Vpp, 75 ohm
Impedance
75 ohm terminated
Y = 0.299R + 0.587G + 0.114B
(R-Y)= 0.701R + 0.587G + 0.114B
(B-Y)=0.299R + 0.587G + 0.886B
1
6
11
15
5
10

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3.3 Compatible Mode Table
VESA MODES
Horizontal
Vertical
Mode
Resolution
Total
Nominal
Frequency
(KHz)
Sync
Polarity
Nominal
Freq.
(Hz)
Sync
Polarit
y
Nominal
Pixel
Clock
(MHz)
VGA
640x480@60Hz
800 x 525
31.469
N
59.940
N
25.175
640x480@72Hz
832 x 520
37.861
N
72.809
N
31.500
640x480@75Hz
840 x 500
37.5
N
75
N
31.500
SVGA
800x600@56Hz
1024 x 625
35.156
P
56.25
P
36.000
800x600@60Hz
1056 x 628
37.879
P
60.317
P
40.000
800x600@72Hz
1040 x 666
48.097
P
72.188
P
40.000
800x600@75Hz
1056 x 625
46.0875
P
75
P
49.5
XGA
1024x768@60Hz
1344x806
48.363
N
60.004
N
65.000
1024x768@70Hz
1328x806
56.476
N
70.069
N
75.000
1024x768@75Hz
1312x800
60.023
P
75.029
P
78.750
WXGA
1360x768@60Hz
1792x795
47.712
P
60.015
P
85.5

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4. Mechanical Instructions
1. Remove the base first with six screws in the base.
2. Remove the screws in red to remove the rear cover.

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3. Remove the speaker cover and the cover-shield.
4. Remove the screws in red to remove the two metallic bracket and button assemble.

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5. Remove the screws and pull out the connecters to remove the board.
.