Sharp LC-20B6US Operation User manual

LC-20B6U-S
SERVICE MANUAL
In the interests of user-safety (Required by safety regulations in some countries) the set should be restored
to its original condition and only parts identical to those specified should be used.
MODEL LC-20B6U-S
SHARP CORPORATION This document has been published to be used for
after sales service only.
The contents are subject to change without notice.
LCD COLOR TELEVISION
CONTENTS
»IMPORTANT SERVICE SAFETY PRECAUTION.........................................................................................2
»SPECIFICATIONS ........................................................................................................................................5
»OPERATION MANUAL .................................................................................................................................6
»DIMENSIONS ...............................................................................................................................................8
»REMOVING OF MAJOR PARTS ..................................................................................................................9
»ADJUSTING PROCEDURE OF EACH SECTION .....................................................................................14
»TROUBLE SHOOTING TABLE ..................................................................................................................28
»MAJOR IC INFORMATIONS ......................................................................................................................33
»CHASSIS LAYOUT .....................................................................................................................................48
»BLOCK DIAGRAM......................................................................................................................................50
»OVERALL WIRING DIAGRAM ...................................................................................................................52
»DESCRIPTION OF SCHEMATIC DIAGRAM .............................................................................................54
»SCHEMATIC DIAGRAM .............................................................................................................................55
»PRINTED WIRING BOARD ASSEMBLIES ................................................................................................81
»REPLACEMENT PARTS LIST....................................................................................................................90
»PACKING OF THE SET............................................................................................................................103
Page
S64T8LC20B6US

LC-20B6U-S
2
CAUTION: FOR CONTINUED
PROTECTIONAGAINSTARISK OF
FIRE REPLACE ONLY WITH SAME
TYPE F3701 (2.0A, 250V), F3702
(1.25A, 250V), AND F6701 (6.3A,
250V) FUSE.
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SAFETY NOTICE
Many electrical and mechanical parts in LCD television
have special safety-related characteristics.
These characteristics are often not evident from visual
inspection, nor can protection afforded by them be
necessarily increased by using replacement components
rated for higher voltage, wattage, etc.
Replacement parts which have these special safety
characteristics are identified in this manual; electrical
componentshaving such features are identified by "å"
IMPORTANT SERVICE SAFETY PRECAUTION
ËService work should be performed only by qualified service technicians who are thor-
oughly familiar with all safety checks and the servicing guidelines which follow:
and shaded areas in the Replacement Parts Lists and
Schematic Diagrams .
For continued protection, replacement parts must be
identical to those used in the original circuit.
The use of a substitute replacement parts which do not
have the same safety characteristics as the factory
recommended replacement parts shown in this service
manual, may create shock, fire or other hazards.
WARNING
1. For continued safety, no modification of any circuit
should be attempted.
2. Disconnect AC power before servicing.
BEFORE RETURNING THE RECEIVER
(Fire & Shock Hazard)
Before returning the receiver to the user, perform
the following safety checks:
1. Inspect all lead dress to make certain that leads are
not pinched, and check that hardware is not lodged
between the chassis and other metal parts in the
receiver.
2. Inspect all protective devices such as non-metallic
control knobs, insulation materials, cabinet backs,
adjustmentandcompartmentcoversorshields,isolation
resistor-capacitornetworks,mechanicalinsulators, etc.
3. To be sure that no shock hazard exists, check for
leakage current in the following manner.
•Plug theAC cord directly into a 110~240 voltAC outlet,
andconnect the DCpower cable intothereceiver's DC
jack. (Do not use an isolation transformer for this test).
•Using two clip leads, connect a 1.5k ohm, 10 watt
resistor paralleled by a 0.15µF capacitor in series with
all exposed metal cabinet parts and a known earth
ground, such as electrical conduit or electrical ground
connected to an earth ground.
•Use anAC voltmeter having with 5000 ohm per volt, or
higher, sensitivity or measure the AC voltage drop
across the resistor.
•Connect the resistor connection to all exposed metal
parts having a return to the chassis (antenna, metal
cabinet, screw heads, knobs and control shafts,
escutcheon, etc.) and measure the AC voltage drop
across the resistor.
All checks must be repeated with the AC cord plug
connection reversed. (If necessary, a nonpolarized
adaptor plug must be used only for the purpose of
completing these checks.)
Anyreadingof0.75V peak(thiscorresponds to0.5mA.
peakAC.)ormoreisexcessiveandindicatesapotential
shockhazardwhichmustbecorrectedbeforereturning
the monitor to the owner.
A V
DVM
AC SCALE
1.5k ohm
10W
TO EXPOSED
METAL PARTS CONNECT TO KNOWN EARTH
GROUND
0.15 µF
TEST PROBE

LC-20B6U-S
3
PRECAUTION: POUR LA
PROTECTION CONTINUE
CONTRE LES RISQUES
D'INCENDIE, REMPLACER LE
FUSIBLE PAR UN FUSIBLE DE
MEME TYPE F3701 (2.0A, 250V),
F3702 (1.25A, 250V) F6701 (6.3A,
250V).
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AVIS POUR LA SECURITE
Denombreuses pièces, électriques etmécaniques,dans
lestéléviseurs présentent des caractéristiques spéciales
relativesàlasécurité,qui ne sont souvent pas évidentes
à vue. Le degré de protection ne peut pas être
nécessairement augmentée en utilisant des pièces de
remplacement étalonnées pour haute tension,
puissance, etc.
Les pièces de remplacement qui présentent ces
caractéristiques sont identifiées dans ce manuel; les
pièces électriques qui présentent ces particularités sont
PRECAUTIONS A PRENDRE LORS DE LA REPARATION
ËNe peut effectuer la réparation qu' un technicien spécialisé qui s'est parfaitement
accoutumé à toute vérification de sécurité et aux conseils suivants.
identifiées par la marque " å" et hachurées dans la
liste des pièces de remplacement et les diagrammes
schématiques.
Pour assurer la protection, ces pièces doivent être
identiques à celles utilisées dans le circuit d'origine.
L'utilisation de pièces qui n'ont pas les mêmes
caractéristiques que les pièces recommandées par
l'usine, indiquées dans ce manuel, peut provoquer des
électrocutions, incendies, radiations X ou autres
accidents.
AVERTISSEMENT
1. N'entreprendre aucune modification de tout circuit.
C'est dangereux.
2. Débrancher le récepteur avant toute réparation.
VERIFICATIONS CONTRE L'INCEN-DIE ET
LE CHOC ELECTRIQUE
Avant de rendre le récepteur à l'utilisateur, effectuer
les vérifications suivantes.
1. Inspecter tous les faisceaux de câbles pour s'assurer
que les fils ne soient pas pincés ou qu'un outil ne soit
pas placé entre le châssis et les autres pièces
métalliques du récepteur.
2. Inspecter tous les dispositifs de protection comme les
boutons de commande non-métalliques, les isolants,
ledosducoffret,lescouverclesoublindagesderéglage
etdecompartiment,lesréseauxderésistance-capacité,
les isolateurs mécaniques, etc.
3. S'assurer qu'il n'y ait pas de danger d'électrocution en
vérifiant la fuite de courant, de la facon suivante:
•Brancher le cordon d'alimentation directem-ent à une
prise de courant de 110-240V. (Ne pas utiliser de
transformateur d'isolation pour cet essai).
•Al'aide de deux fils à pinces, brancher une résistance
de 1.5kΩ10 watts en parallèle avec un condensateur
de 0.15µF en série avec toutes les pièces métalliques
exposées du coffret et une terre connue comme une
conduite électrique ou une prise de terre branchée à la
terre.
•Utiliser un voltmètre CA d'une sensibilité d'au moins
5000Ω/V pour mesurer la chute de tension en travers
de la résistance.
•Toucher avec la sonde d'essai les pièces métalliques
exposéesqui présentent une voiederetour au châssis
(antenne, coffret métallique, tête des vis, arbres de
commande et des boutons, écusson, etc.) et mesurer
la chute de tension CA en-travers de la résistance.
Touteslesvérificationsdoiventêtrerefaites aprèsavoir
inversélaficheducordond'alimentation.(Sinécessaire,
une prise d'adpatation non polarisée peut être utilisée
dans le but de terminer ces vérifications.)
Tous les courants mesurés ne doivent pas dépasser
0,5 mA.
Dans le cas contraire, il y a une possibilité de choc
électrique qui doit être supprimée avant de rendre le
récepteur au client.
A V
DVM
ECHELLE CA
1.5k ohm
10W
0.15 µF
SONDE D'ESSAI
AUX PIECES
METALLIQUES
EXPOSEES
BRANCHER A UNE
TERRE CONNUE

LC-20B6U-S
4
Precautions for using lead-free solder
1 Employing lead-free solder
"All PWBs" of this model employs lead-free solder. The LF symbol indicates lead-free solder, and is attached on
the PWBs and service manuals. The alphabetical character following LF shows the type of lead-free solder.
Example:
2 Using lead-free wire solder
When fixing the PWB soldered with the lead-free solder, apply lead-free wire solder. Repairing with conventional
lead wire solder may cause damage or accident due to cracks.
As the melting point of lead-free solder (Sn-Ag-Cu) is higher than the lead wire solder by 40°C, we recommend
you to use a dedicated soldering bit, if you are not familiar with how to obtain lead-free wire solder or soldering bit,
contact our service station or service branch in your area.
3 Soldering
As the melting point of lead-free solder (Sn-Ag-Cu) is about 220°C which is higher than the conventional lead
solder by 40°C, and as it has poor solder wettability, you may be apt to keep the soldering bit in contact with the
PWB for extended period of time. However, Since the land may be peeled off or the maximum heat-resistance
temperature of parts may be exceeded, remove the bit from the PWB as soon as you confirm the steady soldering
condition.
Lead-free solder contains more tin, and the end of the soldering bit may be easily corroded. Make sure to turn on
and off the power of the bit as required.
If a different type of solder stays on the tip of the soldering bit, it is alloyed with lead-free solder. Clean the bit after
every use of it.
When the tip of the soldering bit is blackened during use, file it with steel wool or fine sandpaper.
Be careful when replacing parts with polarity indication on the PWB silk.
Indicates lead-free solder of tin, silver and copper.
Lead-free wire solder for servicing
Part No, ★Description Code
ZHNDAi123250E J φ0.3mm 250g(1roll) BL
ZHNDAi126500E J φ0.6mm 500g(1roll) BK
ZHNDAi12801KE J φ1.0mm 1kg(1roll) BM
LFa

LC-20B6U-S
5
SPECIFICATIONS
Items
LCD panel 20.1'' Advanced SuperView & BLACK TFT LCD
Number of dots 2,359,296 dots XGA
Video color systems N358, N443, PAL, PAL-M, PAL-N, SECAM, PAL-60
TV Standard (CCIR) NTSC/PAL-M/PAL-N
TV function TV Tuning System PLL 181 ch.
STEREO MTS+SAP
CATV 125 ch.
Y/C FILTER 3DY/C FILTER
Brightness 430 cd/m
2
Viewing angles H: 170°V: 170°
Audio amplifier 2.1 W ×2
Speakers ø2.1 in. (ø5.7 cm), 2 pcs.
COMPONENT1 COMPONENT1-IN, AUDIO-IN
COMPONENT2/AV1 COMPONENT2/AV1-IN, AUDIO-IN, S-VIDEO-IN
Terminals AV-IN2 AV-IN2/AV-OUT
PC-IN PC Connector: 15-pin mini D-sub PC AUDIO: Mini-jack for stereo (ø3.5 mm)
Antenna F-Type
Headphone Mini-jack for stereo (ø3.5 mm)
OSD language English/Spanish/French
Power supply DC 12V, AC 110-240V, 50/60Hz (AC adapter), AC 110-125V (AC cord)
Power consumption 81 W (0.5 W standby) :AC 120V
71 W: DC 12V
Weight 19.0 lbs.(8.6 kg), w/o accessories
Accessories Remote control, Battery (× 2), Antenna cable, AC adapter, RGB cable, AC cord,
Cable holder, Cable clamp, Operation manual, Registration card
Model LC-20B6U
ËAs a part of policy of continuous improvement, SHARP reserves the right to make design and specification changes for product improve-
ment without prior notice.The performance specification figures indicated are nominal values of production units.There may be some
deviations from these values in individual units.

LC-20B6U-S
6
OPERATION MANUAL
Part Names of Main Unit
Controls
•INPUT,CH (
)/( ),VOL (–)/(+) and MENU on the main unit have the same functions as the same buttons on the remote control.
Fundamentally, this operation manual provides a description based on operation using the remote control.
HEADPHONE jack
Plug the headphone mini-plug into the Headphone
jack located on the front of the main unit.
OPC (Optical Picture Control) sensor
Remote sensor
OPC indicator (Optical Picture Control)
The OPC indicator lights up green when the “OPC”is set to “ON”.
POWER/WAKE UP TIMER indicator
POWER indicator lights up green when the power is on, and red
when in the standby mode (the indicator will not light when the
main power is off), and orange when the wake-up timer is set (the
indicator will light when in the standby mode).
To change the vertical angle of the LCD TV
set, tilt the screen up to 5 degrees forward or
10 degrees backward. The LCD TV set can
also be rotated up to 25 degrees to right and
left. Please adjust the angle so that the LCD
TV set can be watched most comfortably.
MAIN POWER
Upper control panel
INPUT
MENU
CH (Channel)
( )/( )
VOL (Volume)
(–)/(+)
Speaker
Speaker
Listening with Headphones
•Plug the headphone mini-plug into the HEADPHONE jack located on the rear of the main unit.
•Headphones are not included in the supplied accessories.
•No sound is heard from the main unit speakers when a headphone mini-plug is connected into the HEADPHONE jack.
"
On-screen display
20
VOLUME
Adjust the sound volume
using VOL (
+
)/(
–
)on the
remote control.
Headphones
Terminals
Carrying handle
RearView
Y
P
B
P
R
AUDIO (L)
AUDIO (R)
VIDEO
AUDIO (R)
AUDIO (L)
AV-IN2/OUT
ANT. (Antenna terminal)
POWER INPUT
(DC 12V)
P
R
P
B
Y/VIDEO
AUDIO (L)
AUDIO (R)
S-VIDEO
COMPONENT2/AV1
COMPONENT1
ANALOG RGB
AUDIO
PC-IN
How to Fix the Cables
•Pull the cables connected to each terminal through the holes and close the left and right terminal covers.
Push the cables into the grooves of the support cover. Insert the cable holder (supplied) from above the
support cover and fix the cables.
Terminal cover
Cable holder
Terminal cover
Support cover
Cable clamp
Whä÷the cables cannot be
pushed into the grooves of
the support cover, use the
cable clamp (supplied) to fix
them. The cable clamp can
be attached by pushing it
into the hole on the stand.

LC-20B6U-S
7
Part Names of Remote Control
DISPLAY
Displays the receiving channel and
the current time for 10 seconds.
AV MODE
Selects preferred AV MODE.
BACKLIGHT
Adjusts the brightness of the screen.
'/"/\/|(Cursor control)
Selectsa desired item on the screen.
MENU
Displays the menu screen.
INPUT
Switches the input source
between COMPONENT1,
COMPONENT2 (or AV1), AV2,
PC and TV mode.
CC
Displays Closed Caption subtitles.
FLASHBACK
Returns to the previous channel.
CH ( )/( )
Selects channel.
Channel Select
Sets the channel.
POWER
Switches the Liquid Crystal Television power on or off.
TV Signals in Your Region
This product is factory set to comply with the TV broadcasting system in the United States. For Brazil, Argentina and Uruguay,
set the color system according to the country before using this product by following the table below.
U.S.A. Color: NTSC NTSC (N358) NTSC (N358)
TV ch: US ch US ch US ch Not required or N/A
Canada, Mexico, Color: NTSC NTSC (N358) NTSC (N358)
Latin America TV ch: US ch US ch US ch Not required or N/A
Brazil Color: PAL-M NTSC (N358) NTSC (N358) Set color system to
TV ch: US ch US ch US ch PAL-M
Argentina, Color: PAL-N NTSC (N358) NTSC (N358) Set color system to
Uruguay TV ch: US ch US ch US ch PAL-N
•The 3 Dimensional Y/C separation circuit* only works when the color system is set to N358 in TV mode and Video mode.
* The 3 Dimensional Y/C separation circuit is used to remove flickering and color bleeding.
* The 3 Dimensional Y/C separation circuit does not function when S-VIDEO or COMPONENT signals are played.
TV broadcasting
system
Factory setting of color system User setting
TV Video TV/Video
Country
PIC. FLIP
Sets the orientation of the picture.
SLEEP
Sets the sleep timer.
ENTER
Executes a command.
MENU RETURN
Returns to the previous screen.
MUTE
Mutes the sound.
AUDIO ONLY
Outputs audio without screen image.
VOL (+)/(–)
Sets the volume.
MTS
Selects audio settings.
Installing Batteries in the Remote Control
Before using the LCD TV set for the first time, install the two “AAA”size batteries supplied in the remote control. When the
batteries become depleted and the remote control fails to operate, replace the batteries with new “AAA”size batteries.
1
Open the battery cover.
2
Insert two “AAA”size batteries.
3
Close the battery cover.
ËPlace batteries with their
terminals corresponding
to the (+) and (–)
indications in the battery
compartment.
Caution!
Precautions regarding batteries
ËImproper use of batteries can result in a leakage of chemicals and/or explosion. Be sure to follow the instructions below.
•Place batteries with their terminals corresponding to the (+) and (–) indications.
•Different types of batteries have different characteristics. Do not mix batteries of different types.
•Do not mix old and new batteries. Mixing old and new batteries can shorten the life of new batteries and/or cause old
batteries to leak chemicals.
•Remove batteries as soon as they are depleted. Chemicals that leak from batteries can cause a rash. If chemical
leakage is found, wipe it off with a cloth.
•The batteries supplied with the LCD TV set may have a shorter operating time due to storage conditions.
•If the remote control is not to be used for an extended period of time, remove the batteries from the remote control.
Preparation
ËEngaging the lower
claw with the remote
control, close the
cover.
ËSlide the cover while
pressing the ( ) part.
+
–
+
–

LC-20B6U-S
8
DIMENSIONS
Unit: inch (mm)
16
11
/
64
(410.5)
12
5
/
32
(308.4)
10
9
/
32
(261)
15
31
/
64
(393)
17
51
/
64
(452)
2
21
/
64
(59)
8
23
/
64
(212)
15
1
/
8
(384)
26
1
/
2
(673)
(including rubber foot)
17
23
/
32
(450)
7
1
/
64
(178)
2
59
/
64
(74)
9
39
/
64
(244)
(including rubber foot)
1
27
/
32
(47)
3
15
/
16
(100)
3
15
/
16
(100)

LC-20B6U-S
9
REMOVING OF MAJOR PARTS
1. Remove the four lock screws from the stand, and detach the stand.
2. Remove the terminal covers (left and right).
3. Remove the three terminal screws.
4. Remove the twelve lock screws from the cabinet B.
5. Cabinet A is order of
5-1
thru
5-6
, and detach the cabinet B.
6. Remove the four lock screws from the stand angle, and detach the reinforcement angle.
7. Disconnect all the connectors from all the PWBs.
Cabinet B
4
3
1
2
2
5-6
Cabinet A
Terminal Cover (S)
Terminal Cover (L)
Stand
5-4
5-3
5-2 5-1
5-5
P4050
CN1
SC1201
SC701
P2003
SC3403
P6701
P3302 P3404
P3303
P4001
P3703
SC2001
P3704
P6707
P6702
P6703
P6704
P6705
P6706
Operation PWB
Reinforcement Angle
Main PWB
R/C, LED PWB Inverter PWB
6
777
7
7
7
7
7
7 7
7
Analog PWB

LC-20B6U-S
10
8. Remove the two lock screws from the operation panel (top cover), and detach the operation panel (top cover).
9. Remove the two lock screws from the operation PWB, and detach the operation PWB.
10. Remove the two lock screws from the R/C, LED PWB, and detach the R/C, LED PWB.
11. Remove the two lock screws each from the speaker boxes (left and right), and detach both the speaker boxes.
Speaker Box (R)
R/C, LED PWB
Analog PWB
Main PWB
Speaker Box (L)
Inverter PWB
Operation panel (Top Cover)
Operation PWB
11 9
8
11
10

LC-20B6U-S
11
12. Remove the two lock screws from the inverter PWB, and detach the inverter PWB.
13. Remove the five lock screws from the main PWB, and undo the claws a and b. Detach the main PWB by lifting
the area around the claws and pulling the PWB out.
14. Remove the four lock screws from the analog PWB, and undo the claws c and d. Detach the chassis frame (right)
from the analog PWB by pulling out the terminals. In the same way, undo the claws e and f, and detach the
chassis frame (left) from the analog PWB by pulling out the terminals.
Note: When detaching the main PWB and analog PWB, be careful not to break the PWB-fixing claws.
Inverter PWB
Main PWB
Analog PWB
f
Chassis Frame (L)
Chassis Frame (R)
13
14
12
e
a
b
c
d

LC-20B6U-S
12
»Precautions in handling the liquid crystal panel
1. Handle it in a clean room. (above 50% humidity)
2. The worker must wear an earth band.
3. Be careful not to drop, vibrate and shock the panel.
4. Use an ionizer. (within 30 cm)
15. Remove the three lock screws from the liquid crystal panel, and detach the liquid crystal panel unit.
16. Remove the prism sheet (H), (V), diffusion sheet and diffusion plate.
17. Remove the lamp unit from the lamp holder (top). Then detach the (bottom)-left and (bottom)-right lamp holders.
18. Remove the upper and lower reflection sheets from the back shield.
Lamp Holder (Bottom)-Left
(LHLDZA368WJKZ)
Lamp Holder (Top)
(LHLDZA365WJKZ)
Lamp Unit
(KLMP-A034WJZZ)
Reflection Sheet (Bottom)
(PSHEPA206WJZZ)
Lamp Holder (Bottom)-Right
(LHLDZA367WJKZ)
Back Shield
(PSLDMA448WJFW)
Lamp Holder (Top)
(LHLDZA365WJKZ)
Diffusion Sheet
(PSHEPA204WJZZ)
Prism Sheet (H)
(PSHEPA203WJZZ)
Diffusion Plate
(PCOVUA035WJZZ)
Prism Sheet (V)
(PSHEPA208WJZZ)
20" LCD Panel Unit
15
Reflection Sheet (Top)
(PSHEPA205WJZZ)
18
16
17

LC-20B6U-S
13
Step Part No. Description
1 QCNW-C459WJQZ ExtensionCable 60-pin Main (SC2001)-Analog (SC3403)
2 QCNW-C461WJQZ Extension Cable 15-pin Main (SC701)-Analog (P3704)
3 QCNW-C458WJQZ Extension Cable 80-pin Main (SC1201)-LCD Panel
»Precautions in servicing the B side (backside) of the main PWB unit
1. Disconnect the FFC from between the main PWB (SC2001) and the analog PWB (SC3403), and then connect the
service-specific extension FFC (flat cable) (QCNW-C459WJQZ).
2. Disconnect the SC701 side of the lead from between the main PWB (SC701) and the analog PWB (P3704), and
then connect the service-specific extension cord (QCNW-B461WJQZ).
3. Disconnect the FFC for connection between the main PWB (SC1201) and LCD panel unit, and then connect the
service-specific extension FFC (flat cable) (QCNW-C458WJQZ).
4. Remove the lock screws from the main PWB, detach the PWB from the chassis frame, and then turn it over to
service.
CN1
SC1201
SC701
SC3403
SC2001
P3704
Main PWB
Main PWB
(Side-B)
Inverter PWB
31 2
4
Analog PWB

LC-20B6U-S
14
ADJUSTING PROCEDURE OF EACH SECTION
1. Pre-adjustment preparations
Use the specific AC adaptor or a stable DC power supply as power source.
LC-20B6U AC adapter: UADP-A065WJPZ
DC power supply: 12 (V), 6.6 (A) or more
(1) How to enter the adjustment process mode
The following two methods are available.
»Whileholdingdown the "INPUT" and "VOLUME (–)" keys on the set, turn ON the power and pressthe "CH (Ù)"
and "VOLUME (–)" keys at once.
»Turn ON the power with either of KEY4 (pin (81) of microprocessor) and KEY5 (pin (82) of microprocessor)
staying at "L".
(2) Key operation in adjustment process
ËBasic operation
»Select a station with the station-selection UP/DOWN key.
»Switch the input with the input selector key.
»Usingthe cursorUP/DOWN key,selectan itemtobe adjusted.(When the cursorDOWN keyispressed withthe
cursor placed on the bottom item, the cursor will move to the top item on the next page. When the cursor UP
key is pressed with the cursor placed on the top item, the cursor will move to the bottom item on the previous
page.)
»Adjust the selected item with the volume UP/DOWN key or the cursor RIGHT/LEFT key
»Pressing the menu key will move the cursor to the next item. (When the menu key is pressed with the cursor
placed on the bottom item, the cursor will move to the top item on the next page.)
»Pressingthemanualmemorykeywillreturnthecursortothetopitem. (Whenthemanualmemorykeyispressed
with the cursor placed on the top item, the cursor will move to the top item on the previous page.)
»Pressing the auto preset key will move the cursor to the top item on the next page.
ËHierarchical structure
»When the ENTER key is pressed with the cursor placed on an item other than I2C DATA on page 9, the setting
page corresponding to the selected item will appear.
»To exit each setting page, press the "Previous Screen" key.
Initialization
1. Set both pins (81) and (82) of IC2001 (microprocessor) to GND and turn ON the power
2. Check the model name (A625). *Note: MODEL cannot be changed.
3. Inch size selection
Check INCH SIZE (20) * Note: INCH SIZE cannot be changed.
2.Adjusting procedure
(1)AD converter level adjustment
1D3 input
1) D3 75% color bar signal input
Device name: LEADER LT446
Signal name: COLOR BAR 75%
Setting: 01: 1920 x 1080 / 60i
H: 33.72kHz, V: 29.97Hz
2) Set AUTO GAIN-OFFSET1 on page 7 of the adjustment process menu to ON.
2PC input
1) VGA 75% color bar signal input
Device name: LEADER LT446
Signal name: COLOR BAR 75%
Setting: 07: 640 x 480 / 60P
H: 31.47kHz, V: 59.94Hz
2) Set AUTO GAIN-OFFSET2 on page 8 of the adjustment process menu to ON.

LC-20B6U-S
15
(2)Adjustment of TAMP
1) 75% standard color bar signal reception
2) If the reading of "YDATA" on page 2 of the adjustment process menu falls outside the range shown in the table
below, adjust "NTSC TAMP" on this page so that the reading of "YDATA" falls within this range.
* Note that settings may vary with models.
3) Set "PAL-M TAMP" and "PAL-N TAMP" to the same value to which "NTSC TAMP" is set.
Reference
(Page 2 of adjustment process menu)
Model LC-20B6U-S
Setting 157-160
0
2
1
|
2
C
T
Y
T
N
P
P
3
O
A
D
A
T
A
A
4
M
M
A
M
S
L
L
5
P
T
P
C
-
-
6
B
A
M
N
7
I
L
H
T
8
A
A
T
T
9
S
M
A
A
10
P
P
11 12 13 14 15 16 17 18 19 20 21
4
1
1
1
22
2
5
5
6
9
9
9
23
7
7
9
0
5
5
5
24 25 26
0
1
2
3
4
5
6
7
8
Y Data
(White 75%)

LC-20B6U-S
16
(3)Adjustment of white balance
1) How to adjust the white balance
1Select the component -480i input.
2Adjust "R CUTOFF2" and "B CUTOFF2" so that "White 20%" takes on the following WB target values.
Caution: "G CUTOFF2" should be fixed.
3Adjust two strong colors of "R/G/B-GAIN" downward so that "White 80%" takes on the WB target values.
Caution: Any one of "R/G/B-GAIN" should be fixed at 64.
4Repeat steps 2and 3so that "White 20%" and "White 80%" takes on the target values.
5Enter the values of "R/B_CUTOFF2" and "R/G/B-GAIN" set in steps 2to 4in the corresponding items of
"Composite adjustment", "Component -1080i adjustment" and "PC-VGA adjustment" shown below.
6Selectthecompositeinputandcheckthat"White20%"and"White80%"arewithintheinspectionspecifications
on the next page.
Caution: The component Ys output signal of the automatic regulator should be used also when the composite
input is selected. In the case of the CVBS output, the signal level is different.
7If "White 20%" and "White 80%" are not within the inspection specifications, make the adjustment described
in steps 2to 4.
8Select the component -1080i input and check that "White 20%" and "White 80%" are within the inspection
specifications on the next page.
9If "White 20%" and "White 80%" are not within the inspection specifications, make the adjustment described
in steps 2to 4.
0SelectthePC-VGA inputand checkthat "White20%" and"White 80%"are withinthe inspectionspecifications
on the next page.
qIf "White 20%" and "White 80%" are not within the inspection specifications, make the adjustment described
in steps 2to 4.
2) Adjustment value
•Composite adjustment...RGB CUTOFF2 and RGB-GAIN on page 3 of adjustment process menu
•Component -480i adjustment...A RGB CUTOFF2 and A RGB-GAIN on page 4 of adjustment process menu
•Component -1081i adjustment...D RGB CUTOFF2 and D RGB-GAIN on page 5 of adjustment process menu
•PC-VGA adjustment...PC RGB CUTOFF2 and PC RGB-GAIN on page 5 of adjustment process menu
3) WB target value (numeric values for MINOLTA CA-210)
Adjustment value Adjustment specifications
White 80% x=0.295 ±0.006
y=0.305 ±0.006
White 20% x=0.292 ±0.006
y=0.301 ±0.006
Remarks The numeric values shown above are for MINOLTA CA-210.
(Reference) White 80%...luminance: 220 cd/m2, About 8000K
White 20%...luminance: 9 cd/m2, About 8400K
4) WB adjustment range
R/G/B CUTOFF2: –20 to +20 (G CUTOFF2 fixed at 0)
R/G/B GAIN: 36 to 64 (One of the colors fixed at 64)

LC-20B6U-S
17
3.Factory setting
(1) Factory adjustment procedure
While holding down the "INPUT" and "VOLUME (–)" keys on the set, turn ON the power and press the "CH (ù)"
and "VOLUME (+)" keys at once.
(2) DESCRIPTION OF FACTORY SETTINGS
ITEM SETTING
OTHER THAN MENU
STARTUP OF EZ SETUPAT POWER-ON ON
SELECT LANGUAGE ENGLISH
CH-SETTING ON
AUTO CLOCK ON
LAST CHANNEL 2ch
LAST TV/INPUT TV
FLASH BACK 2ch
VOLUME 20
MENU-PICTURE
AV MODE DYNAMIC
OPC OFF
BACKLIGHT BRIGHT (17)
CONTRAST 56
BRIGHTNESS 0
COLOR +2
TINT 0
SHARPNESS +4
ADVANCED COLOR TEMP. MIDDLE
RED 0
GREEN 0
BLUE 0
I/P SETTING PROGRESSIVE
NOISE CLEAN OFF
FILM MODE OFF
QUICK SHOOT ON
MENU-AUDIO
TREBLE 0
BASS 0
BALANCE 0
WIDE SOUND OFF
SPEECH EMPHASIS OFF
PC SOUND SELECT PC
FOR STANDARD FOR MOVIE FOR GAME
OFF OFF OFF
BRIGHT (17) BRIGHT (17) NORMAL(9)
50 50 50
000
0+20
000
000

LC-20B6U-S
18
MENU-SETUP
CH-SETTING AIR/CABLE AIR
CH MEMORY SKIP ALL CH ON
MTS STEREO
CLOCK SET AUTO EDS CH AUTO
MENU DST OFF
TIME 12:00AM
TIME DISPLAY ON
COMP. 2/AV1 SELECT COMPONENT2
AV2 IN/OUT IN
V-CHIP BLOCK INPUT SECRET NO. CLEAR
MPAA G, PG, PG-13, R, NC-17, X ALL CLEAR
TV GUIDELINES TV-Y, TV-Y7, TV-G, TV-PG, TV-14, TV-MA ALL CLEAR
BLOCK CONTENT D, L, S, V, FV ALL CLEAR
CAN. ENGLISH RATINGS C, C8+, G, PG, 14+, 18+ ALL CLEAR
CAN. FRENCH RATINGS G, 8 ans+, 13 ans+, 16 ans+, 18 ans+ ALL CLEAR
STATUS OFF
CLOSED CAPTION OFF
COLOR SYSTEM (FOR TV) N358
COLOR SYSTEM (FOR AV 1 AND 2) AUTO
PC SETTING INPUT SIGNAL 1024 x 768
FINE SYNC. H. POS. 0
V. POS. 0
CLOCK 0
PHASE 0
LANGUAGE ENGLISH
MENU-OPTION
VIEW MODE 4 : 3
AUDIO ONLY OFF
SLEEP TIMER OFF
WAKEUP TIMER TIMER OFF
TIME 12:00AM
CHANNEL 2
VOLUME 20
NO SIGNAL OFF DISABLE
NO OPERATION OFF DISABLE
POWER MANAGEMENT OFF
PICTURE FLIP NORMAL

LC-20B6U-S
19
Page No. Item Initial Function Response precautions on servicing
Value (Do not change other items than designated.)
1 MODEL A625 MODEL NAME SELECTION CANNOT BE CHANGED.
INCH SIZE 20 INCH SIZE SELECTION
USED FOR INITIALIZATION. MUST NOT BE
CHANGED IN OTHER CASES.
IF CHANGED, IT IS NECESSARY TO PERFORM
DATA REWRITING AND READJUSTING
ERROR NO RESET 0 LAMP ERROR COUNT & RESET REFER TO LAMP ERROR DETECTION.
PUBLIC MODE OFF HOTEL MODE SETTING NOT USED
V-CHIP 1 VCHIP LINE MUTE SETTING NOT USED
CANADIAN VCHIP ON CANADIAN VCHIP SETTING NOT USED
EXT CONTROL OFF BUS UART OPEN NOT USED
BLUE BACK 0 BLUE BACKGROUND ON•OFF SETTING NOT USED
ROM AND GAIBU VERSION NUMBERS SHOULD BE DISPLAYED AT THE BOTTOM.
VIDEO ADJUSTMENT
2 COM BIAS 427 COMMON BIASADJUSTMENT NOT USED
TAMP L 157
Y LOWER LIMIT SETTING FOR TAMP ADJUSTMENT NOT USED
YDATA — Y UPPER LIMIT SETTING FOR TAMP ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
TAMP H 160 Y UPPER LIMIT SETTING FOR TAMP ADJUSTMENT NOT USED
NTSC TAMP 70 TAMP ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PAL-M TAMP 70 TAMP ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PAL-N TAMP 70 TAMP ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
BACKGROUND ADJUSTMENT
3 R CUTOFF 0 RED CUTOFFADJUSTMENT REFER TO METHOD OFADJUSTMENT.
G CUTOFF 0 GREEN CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
B CUTOFF 0 BLUE CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
GAIN1 64 WHITE BALANCE ADJUSTMENT REFERTO METHOD OFADJUSTMENT.
GAIN2 64 WHITE BALANCE ADJUSTMENT REFERTO METHOD OFADJUSTMENT.
REF 0 REFERENCE SETTING REFER TO METHOD OF ADJUSTMENT.
R CUTOFF2 0 RED CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
G CUTOFF2 0 GREEN CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
B CUTOFF2 0 BLUE CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
R-GAIN 64 WHITE BALANCE ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
G-GAIN 64 WHITE BALANCE ADJUSTMENT REFERTO METHOD OFADJUSTMENT.
B-GAIN 64 WHITE BALANCE ADJUSTMENT REFERTO METHOD OFADJUSTMENT.
525I/625I/525P/625P BACKGROUND ADJUSTMENT
4 A R CUTOFF 0
525I/625I/525P/625P RED CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AG CUTOFF 0 525I/625I/525P/625P GREEN CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AB CUTOFF 0 525I/625I/525P/625P BLUE CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AGAIN1 64 525I/625I/525P/625P WHITE BALANCE ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AGAIN2 64 525I/625I/525P/625P WHITE BALANCE ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
A REF 0 525I/625I/525P/625P REFERENCE SETTING REFER TO METHOD OF ADJUSTMENT.
AR CUTOFF2 0 525I/625I/525P/625P RED CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AG CUTOFF2 0 525I/625I/525P/625P GREEN CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AB CUTOFF2 0 525I/625I/525P/625P BLUE CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
A R-GAIN 64 525I/625I/525P/625P WHITE BALANCE ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
A G-GAIN 64 525I/625I/525P/625P WHITE BALANCE ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
A B-GAIN 64 525I/625I/525P/625P WHITE BALANCE ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
ADJUSTMENT PROCESS 1st LEVEL ITEM DEFAULT TABLE
BASIC SETTING

LC-20B6U-S
20
Page No. Item Initial Function Response precautions on servicing
Value (Do not change other items than designated.)
1125I/750P BACKGROUND ADJUSTMENT
5 D R CUTOFF 0 1125I/750P
RED CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D G CUTOFF 0 1125I/750P GREEN CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D B CUTOFF 0 1125I/750P BLUE CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D GAIN1 64 1125I/750P WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D GAIN2 64 1125I/750P WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D REF 0 1125I/750P PREFERENCE SETTING REFER TO METHOD OF ADJUSTMENT.
D R CUTOFF2 0 1125I/750P RED CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D G CUTOFF2 0 1125I/750P GREEN CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D B CUTOFF2 0 1125I/750P BLUE CUTOFF ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D R-GAIN 64 1125I/750P WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D G-GAIN 64 1125I/750P WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
D B-GAIN 64 1125I/750P WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PC BACKGROUNDADJUSTMENT
6 PC R CUTOFF 0 PC RED CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PC G CUTOFF 0 PC GREEN CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PC B CUTOFF 0 PC BLUE CUTOFFADJUSTMENT REFERTO METHOD OFADJUSTMENT.
PC GAIN1 64 PC WHITE BALANCE ADJUSTMENT REFER TO METHOD OFADJUSTMENT.
PC GAIN2 64 PC WHITE BALANCE ADJUSTMENT REFER TO METHOD OFADJUSTMENT.
PC REF 0 PC PREFERENCE SETTING REFER TO METHOD OFADJUSTMENT.
PC R CUTOFF2 0 PC RED CUTOFFADJUSTMENT REFER TO METHOD OFADJUSTMENT.
PC G CUTOFF2 0 PC GREEN CUTOFFADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PC B CUTOFF2 0 PC BLUE CUTOFFADJUSTMENT REFERTO METHOD OFADJUSTMENT.
PC R-GAIN 64 PC WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PC G-GAIN 64 PC WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
PC B-GAIN 64 PC WHITE BALANCEADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
1125I/750P AD ADJUSTMENT
7 AD9883 DATA 0 AD9883 DATA WRITE AND READ NOT USED
AD9883 DATA WAIT WRITE AND READ EXECUTION NOT USED
AUTO GAIN-OFFSET1 OFF AD9883 GAIN AND OFFSET AUTO ADJUSTMENT OFF/RUN
REFER TO METHOD OF ADJUSTMENT.
AD R GAIN 30 1125I/750P INPUT RED GAIN ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AD G GAIN 125 1125I/750P INPUT GREEN GAINADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AD B GAIN 30 1125I/750P INPUT BLUE GAIN ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AD R OFFSET 64 1125I/750P INPUT RED OFFSETADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AD G OFFSET 50 1125I/750P INPUT GREEN OFFSET ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
AD B OFFSET 64 1125I/750P INPUT BLUE OFFSET ADJUSTMENT REFER TO METHOD OF ADJUSTMENT.
RGTAR E0 1125I/750P INPUT RED OFFSET ADJUSTMENT
NOT USED
GGTAR 98
1125I/750P INPUT GREEN OFFSET ADJUSTMENT
NOT USED
BGTAR E0
1125I/750P INPUT BLUE OFFSET ADJUSTMENT
NOT USED
RGCAL —
DISPLAY OF Y LEVEL CHROMA CALCULATED VALUE
NOT USED
GGCAL — DISPLAY OF Y LEVEL CHROMA CALCULATED VALUE NOT USED
BGCAL — DISPLAY OF Y LEVEL CHROMA CALCULATED VALUE NOT USED
ROCAL — DISPLAY OF Y LEVEL WHITE LEVEL CALCULATED VALUE OF CLAMP AREA NOT USED
GOCAL — DISPLAY OF Y LEVEL WHITE LEVEL CALCULATED VALUE OF CLAMP AREA NOT USED
BOCAL — DISPLAY OF Y LEVEL WHITE LEVEL CALCULATED VALUE OF CLAMP AREA NOT USED