Hitachi 26LD8000TA User manual

SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.
LCD Television
July 2005 Digital Media Division
YK No.019E
SERVICE MANUAL 26LD8000TA
Be sure to read this manual before servicing. To ensure safety from fire, electric shock, injury, harmful radiation
and materials, various measures are provided in this LCD TV. Be sure to read cautionary items described in
the manual before servicing. These servicing instructions are for use by qualified service personnel only. To
reduce the risk of electric shock, do not perform any servicing other than that described in the operating
instructions unless you are qualified to do so.
Caution
1. Features --------------------------------------------------3
2. Specifications--------------------------------------------4
3. Component names -------------------------------------5
4. Service point ---------------------------------------------7
5. Adjustment -----------------------------------------------8
6. Troubleshooting--------------------------------------- 16
7. Self-diagnosis function ------------------------------ 21
8. Block diagram ----------------------------------------- 23
9. Wiring diagram ---------------------------------------- 25
10.Circuit diagram ---------------------------------------- 26
11.Printed wiring board diagram ---------------------- 42
12.Disassembly diagram-------------------------------- 46
13.Replacement parts list------------------------------- 48
Contents
1. Replacement work should be started after the Panel Module and the AC/DC Power supply have become
sufficiently cool.
2. Special care should be taken when working near the display area in order not to damage its surface.
3. The Panel Module should not be touched with bare hands in order to protect its surface from blemishes
and damage.
4. It is recommended that you use clean soft gloves during the replacement work in order to protect not only
the display area of the Panel Module but also yourself.
Service Warning

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CAUTION FOR SAFETY
Please read this page before repair the TV.
The following safety precautions are designed to help you stay safe and prevent accidents during the repair
work.
zPlease take note of these cautionary flags.
Warning This means "Potential to sustain injury or even death."
Caution This means "Potential to sustain breakage or irreparable damage."
zAlso note these cautionary icons
This means "CAUTION" This means "MUST"
This means "POTENTIAL ELECTRIC
SHOCK" This means "DO NOT"

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WARNING
Follow instructions. Must use same types of wires and components.
The cabinet, chassis, and labels are parts
that require attention. You must follow the
caution notes and safety instructions
presented throughout this User Manual to
prevent damage to them or injury to
yourself.
Prevent electric shock.
The TV uses special tubes and tapes
made from insulated materials. Moreover,
some materials are kept from making
contact with the PWB for the sake of
safety.Internal leads are kept from hot
parts or high voltage parts by means of
clamps or other measures. As such, you
must restored these parts to their original
conditions in order to prevent electric
shock or fire.
Perform safety check when done.
Exercise caution while working on the
device as the TV contains high voltage
parts and
supply.It is possible to sustain severe
injury or death if you accidentally touch
the wrong parts.You must disconnect the
power supply while servicing,
reassembling, or change parts. If you
touch a live connection it is possible to
sustain severe injury or death.
Use recommended components.
Every part (such as removed screws,
components, and wiring) must be
restored to their prior conditions after
servicing.Be sure to check everything that
was repaired for damage or mistakes.
Also measure the insulated impedance
with a meg-ohm meter to confirm that the
impedance value is more than 4M ohm.If
the impedance value is less than 4M
ohm, then electric shock or fire may
result.
Use only the recommended components
or componentst that structurally identical
to the originals. This is to ensure safety
and reliability. Pay special attention to
parts in the parts list and circuit diagrams
marked with . If you use
non-recommended components, then
electric shock or fire may result.

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PRECAUTIONS
zCleaning the TV’s LCD screen panel
Before cleaning the TV, turn it off and disconnect the power plug from the power outlet. To prevent scratching
or damaging of the LCD screen face, do not knock or rub the surface with sharp or hard objects. Clean the
screen with a soft cloth moistened with warm water and dry with a second soft cloth. If it is not enough, then
use a cloth with mild detergent. Do not use harsh or abrasive cleaners.
zCleaning the TV's cabinet
Use a soft cloth to clean the TV's cabinet and control panel. When excessively soiled, dilute a neutral
detergent in water, wet and wring out the soft cloth in it, gently clean the cabinet, and then wipe it down with a
dry soft cloth.
Never use acid/alkaline detergents, alcoholic detergents, abrasive cleaners, powder soaps, OA cleaners, car
wax, glass cleaners, and so on. They will cause discoloration, scratches or cracks.
1. Features
zEnhanced definition LCD display panel
The 26-inch color LCD display panel, with a resolution of 1366 (H) x 768(V) pixels, creates a widescreen
picture. This panel features a thin form factor and can be hung on a wall with an optional wall mounting kit.
zHigh Performance Digital Processor
This panel displays a wide range of personal computer signals from 640 x 480, 800 x 600 SVGA to 1280 x
768 WXGA.(RGB Analog input).
zEasy-to-use remote control and on-screen display system
The included remote control operates all TV functions. Futhermore, the on-screen display system shows
the status of the control settings in an easy-to-view fashion.
zPower saving system
When connected to a VESA DPMS-compliant PC, the TV cuts its power consumption while idle.

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2. Specifications
Display
dimensions Approx. 26.005nches (604 (H) x 323 (V) mm, diagonal 600.53mm)
Panel
Resolution 1366 (H) x 768 (V) pixels
Net dimensions 661.9 (W) x 522.5 (H) x 266.9(D) mm (With Base)
Net weight 18 kg (With Base)
Temperatur Operating: 0°C to 40°C, Storage: -15°C to 50°C
Ambient
conditions Relative umidity Operating: 20% to 80%, Storage: 20% to 90% (non-condensing)
Power supply AC100 - 240V, 50/60Hz
Power consumption/at standby <120W / <1W
Audio output Build in 10W + 10W (4 Ω)
(RGB input)
Input terminals RGB1-VGA audio input terminal (3.5mm Stereo Mini Jack)
RGB1-VGA analog RGB input terminal (D-sub 15-pin)
Video signals 0.7 V
Input signals
Sync signals
H/V separate, TTL level [2kΩ]
H/V composite, TTL level [2kΩ]
Sync on green, 0.3 Vp-p [75Ω]
Recommended signal 5 modes
(Video input)
Input terminals
AV1 : Component input (Y-PbPr/Y-CbCr) (RCA)
AV1 : L/R audio input terminal(RCA)AV1 : L/R audio input terminal(RCA)
AV2 : Component input (Y-PbPr/Y-CbCr) (RCA)
AV2 : L/R audio input terminal(RCA)AV1 : L/R audio input terminal(RCA)
AV3 : Composite video input terminal(RCA)
AV3 : S video input teminal
AV3 : L/R audio input terminal(RCA)
AV4 : Composite video input terminal(RCA)
AV4 : S video input teminal
AV4 : L/R audio input terminal(RCA)
Input signals
Video signals
AV1 : NTSC-M / PAL
AV2 : NTSC-M / PAL
AV3 : NTSC-M / PAL / SECAM
AV4 : NTSC-M / PAL / SECAM
Video output Signal OUTPUT(TV): composite video TV-output terminal (RCA)
OUTPUT(TV): L/R audio TV- output terminal (RCA)
Recommended signal 5 modes
(TV RF input)
Input signals Input terminals Analog RF input terminal (NTSC/PAL/SECAM)
zIt takes at least 30 minutes to attain the maximum picture quality.
Applicable video signals for each input terminal
RCA D-sub
Signal Type
Terminal Composite
S-video component
RGB Remarks
AV1
{480i/480p/1080i/720p inputs (PAL).
AV2
{480i/480p/1080i/720p inputs (PAL).
AV3 {{
AV4 {{
RGB {
({: Avaliable)

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3..Component names
¾[Main unit]
Control panel
zAn Adjustment buttons are located on the top of
the control panel
zIndications for each button's function can be found
on the inside of the control panel cover.
1. SUB-POWER 4. VOL X7.MENU
2. PROGRAM S4. RIGHTX7.ENTER
2. UP S5. VOL W
3. PROGRAM T5. LEFT W
3. DOWN T6. INPUT Normal Button Action
6.EXIT Button Action when MENU engaged
The main power switch is located at the right
side of the back.

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¾[Remote Control]

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4.Service points
zLead-free solder
This product uses lead-free solder (unleaded) to help protect the environment. Please read these instructions
before attempting any soldering work.
Caution: Always wear safety glasses to prevent fumes or molten solder from getting into
the eyes. Lead-free solder can splatter at high temperatures (600℃).
Lead-free solder indicator
Printed circuit boards using lead-free solder are engraved with an label.
Properties of lead-free solder
The melting point of lead-free solder is 40-50℃higher than leaded solder.
Servicing solder
Solder with an alloy composition of Sn-3.0Ag-0.5Cu or Sn-0.7Cu is recommended. Although servicing with
leaded solder is possible, there are a few precautions that have to be taken. (Not taking these precautions
may cause the solder to not harden properly, and lead to consequent malfunctions.)
Precautions when using leaded solder
zRemove all lead-free solder from soldered joints when replacing components.
zIf leaded solder should be added to existing lead free joints, mix in the leaded solder thoroughly after the
lead-free solder has been completely melted (do not apply the soldering iron without solder).
Servicing soldering iron
A soldering iron with a temperature setting capability (temperature control function) is recommended.
The melting point of lead-free solder is higher than leaded solder. Use a soldering iron that maintains a high
stable temperature (large heat capacity), and that allows temperature adjustment according to the part being
serviced, to avoid poor servicing performance.
Recommended soldering iron:
zSoldering iron with temperature control function (temperature range: 320-450℃)
Recommended temperature range per part:
Part Soldering iron temperature
Mounting (chips) on mounted PCB 320℃±30℃
Mounting (chips) on empty PCB 380℃±30℃
Chassis, metallic shield, etc. 420℃±30℃
(1) IR PWB, KEY PWB, SW PWB,2* I/O PWB
(2) MAIN PWB
(3) POWER BOARD
The PWB assembl
y
which has used lead free solder

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5.Adjustment
5.1 SERVICE (FACTORY) MODE ACCESS
This model has a Factory Mode, where the technician can access and adjust some of the color temperature
settings. The Factory Mode has several different appearances, depending on the input signal.
Picture Setting
for Factory Model NTSC
Table1 TV
Table2 AV (composite)/SV(S-Video)
Table3 SV(S-video)
Table4 480i(component)
Table5 480p(component)
Table6 1080i/60(component)
Table7 720P/60(component)
Picture Setting
for Factory Model PAL
Table1 TV
Table2 AV (composite)/SV(S-Video)
Table3 SV(S-video)
Table4 576i(component)
Table5 576p(component)
Table6 1080i/50(component)
Table7 720P/50(component)
Preliminary
1. To access the Factory Mode, the TV must be
running.
Procedure
2. Press and hold the #3 and #4 button (PROGRAM Tand VOLUMES). ① ②
3. While continuing to hold the #3 and #4 button, press and hold the #1 button (SUB-POWER).
4. After both buttons have been held down for five (5) seconds, first release the #1 button, then release the
#3 and #4 button.
5. As stated previously, the input that the TV had selected at the time will determine which actual FACTORY
MODE display will show up. (See next page)

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zFACTORY MODE NAVIGATION
To navigate through the different menu items, use the Sor Tbutton on the remote control. The menu items
will be high-lighted green as navigation occurs. To access a particular adjustment parameter, use the
“ENTER” button on the remote control, which will cause a new menu to appear. To back up from the
FACTORY MODE, use the RETURN or EXIT button on the remote control. To leave the FACTORY MODE,
press POWER button on the remote control.
ENTER

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Menu Function Description
Video
Picture Mode OSD menu video mode default setting
Picture Display Contrast adjustment ( Back- end )
Brightness Display Brightness adjustment ( Back- end )
Tint Display Hue adjustment ( Back- end )
Color Display Saturation adjustment ( Back- end )
Detail Display Sharpness adjustment ( Back- end )
Backlight LCD backlight control ( Back- end )
Color
Temperature Color temperature default setting ( High or Low )
ADC
ADC Gain - R ADC input signal gain adjustment ( R/Pr ) , For D1 ~ D4 and PC only
ADC Gain - G ADC input signal gain adjustment ( G/Y ) , For D1 ~ D4 and PC only
ADC Gain - B ADC input signal gain adjustment ( B/Pb) , For D1 ~ D4 and PC only
TCD3
TCD3 Con. Video decoder contrast adjustment ( Front- end )
TCD3 Bri. Video decoder brightness adjustment ( Front- end )
TCD3 Hue Video decoder Hue adjustment ( Front- end )
TCD3 Sat. Video decoder Cr Saturation adjustment ( Front- end )
TCD3 Sat. Video decoder Cb Saturation adjustment ( Front- end )
YC Delay Video decoder YC delay adjustment ( Front- end )
Peaking Range
Video decoder sharpness peaking range ( Front- end )
Ypeak = Y + YH * (peak_gain/peak_range) where Y is the luma and YH
is the high frequency luma only
Peaking Gain Video decoder sharpness peaking gain ( Front- end )
Peaking Enable Video decoder sharpness peaking function enable ( Front- end )
Scalar
Scalar Con - R
Output R contrast factor adustment ( color temperature function )
Output R = (( 'Output R + (Scalar Off-R)) * (Scalar Con-R) + (Scalar
Bri-R)
Scalar Con - G
Output G contrast factor adustment ( color temperature function )
Output G = (( 'Output G + (Scalar Off-G)) * (Scalar Con-G) + (Scalar
Bri-G)
Scalar Con - B
Output B contrast factor adjustment ( color temperature function )
Output B = (( 'Output B + (Scalar Off-B)) * (Scalar Con-B) + (Scalar
Bri-B)
Scalar Bri - R Output R brightness factor adustment ( color temperature function )
Scalar Bri - G Output G brightness factor adustment ( color temperature function )

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Scalar Bri - B Output B brightness factor adustment ( color temperature function )
Scalar Off - R Output R offset factor adustment ( color temperature function )
Scalar Off - G Output G offset factor adustment ( color temperature function )
Scalar Off - B Output B offset factor adustment ( color temperature function )
Display
Disp MP BL Display sharpness band pass gain of peaking adjustment ( Back- end ) ,
OSD sharpness adjustment item
HSharp LP Display sharpness low pass gain of peaking adjustment ( Back- end )
Hsharp HP Display sharpness high pass gain of peaking adjustment ( Back- end ) ,
OSD sharpness adjustment item
Vsharp Display Vertical sharpness adjustment ( Back- end )
Black Ext. Start
Black stretch start-point control factor. Higher value means more black
stretch
( Back- end )
Black Ext.
Gain1 Black stretch gain1
Black Ext.
Gain2 Black stretch gain2
U Delay Display U delay ( comparing with Y )
V Delay Display Y delay ( comparing with V )
Color
Process
Skin Range
Low Skin color adjustment active range low
Skin Range
High Skin color adjustment active range high
Skin Gain Low Skin color adjustment gain of range low
Skin Gain High Skin color adjustment gain of range high
Skin Color
Enable Skin color adjustment function enable
Green Str.
Angle Green stretch active range ( UV domain green color active angle )
Green Str. Gain Green stretch gain
Green Str.
Enable Green stretch function enable
Blue Threshold Blue add function active threshold
Blue Circle
Range Blue add function active range
Blue Add Blue add function enable

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Enable
Blue Gain Blue add gain
zCOLOR TEMPERATURE ADJUSTMENTS
Following the procedures to make the color temperature adjustments. Note that a colorimetry meter (such as
a Minolta CA-210) is required to measure the actual screen color temperature.
Low : x=0.301 +/- 0.01, y=0.314 +/- 0.01 = Color Temp.: 7500K
High : x=0.266 +/- 0.01, y=0.264 +/- 0.01 = Color Temp.: 15000K
5.2 Firmware update
This model has a Debbug Mode, where the technician can debbug and update the firmware.
Preliminary
1.To access the Bebbug Mode, the TV must be
running.
Procedure
2. Press and hold the #2 and #5 button (PROGRAM Sand VOLUMET).
3. After both buttons have been held down for five (5) seconds, then release the #2 and #5 button.
4. Click IAPWriter.EXE
5. Following window will be shown after IAPWriter.EXE is executed.

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6. Load BIN file.
7. Click OK button

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8. Click Write Device icon
9. IAP is finished while following massage is shown.
10. After IAP is done, please disconnect and reconnect AC power switch and do initialization.

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5.3 Initialization
This model has a Initialization Mode, where the technician can initial the EEPROM.
Preliminary
1.To access the Bebbug Mode, the TV must be
running.
Procedure ①②
6. Press and hold the #4 and #5 button (VOLUMESand VOLUME T).
7. While continuing to hold the #4 and #5 button, press and hold the #1 button (SUB-POWER).
8. After both buttons have been held down for five (5) seconds, first release the #1 button, then release the
#4 and #5 button.
9. As stated previously, the input that the TV had selected at the time will determine which actual
INITIALIZATION display will show up. (See below)

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6.Troubleshooting
The flow chart shown below will help you to troubleshoot your TV set with it doesn’t display normally. Each
procedure offers a simple way to check for system errors. Before starting, ensure that there is a signal in and
that the TV is turned on.

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