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5. Adjustment

5-1 VLSBIAS/15V voltage adjustment

Shift to Item of VLS BIAS cursor up/down key, and select the value by cursor right/left key. Connect the
digital voltage meter to MAIN PWB TP4101/No.30 pin of panel gate socket CN4102, and adjust to be
15.00±0.05V by the cursor up/down key.

5-2 GRAY LEVEL/14.5V voltage adjustment

Shift to Item of GRAY LEVEL by cursor up/down key, and select the value by cursor right/left key. Connect
the digital voltage meter to MAIN PWB TP4104/near IC4105, and adjust to be 14.50±0.05V by cursor up/
down key.
This adjustment should be correctly made because this power voltage is a reference voltage of tonal
voltage.

5-3 COMBIAS adjustment

Shift to Item of COMBIAS by cursor up/down key, and select the value by cursor right/left key. If the value is
varied by cursor up/down key, the test pattern is made, so adjustment should be made so that the flicker
near the screen center becomes minimum.

5-4 Background adjustment

With AVC center connected, start the set and adjust the display background.
Sequence:

~

Display the screen for adjustment/High-side 200 gradation & Low-side 48 gradation.

~

Adjust ROFFSET, GOFFSET and BOFFSET to allow 200-gradation patterns as a standard.
Adjust the chromaticity of High pattern/screen left to be x=0.278 and y=0.283.

~

Adjust R GAMMA, G GAMMA and B GAMMA to allow 48-gradation patterns as a standard.
Adjust the chromaticity of Low pattern/screen right to be x=0.235 and y=0.230.

The above adjustment can be made in the following method:

~

Adjustment with RS-232C

~

Prepare the personal computer with
WINDOWS95/98/Me/2000/xp inputted and provided with COM port/RS-232C, together with RS-232C
cross cable.

~

Start the set with RS232C cable connected.

~

Start the terminal software. The free ware normally found on the Internet is allowed.

~

The following should be set:
Baud rate        9600
Data             8bits
Parity            None
Stop              1bit
Flow control       None

~

If they are set correctly, press ENTER key on the personal computer. "ERR" appears atop the terminal
software.

~

In this state, enter the command, listed below, and "ENTER" on the keyboard for adjustment.
Press "ENTER" and make sure that "OK" appears on the terminal software.
If "ERR" appears, try again.

RS232C commands list

Command

MSET1001

MOFR

~~~~

MOFG

~~~~

MOFB

~~~~

MGAR

~~~~

MGAG

~~~~

MGAB

~~~~

MINF0000

MINF0001

MINF0002

Function

Background adjustment started.

R OFFSET value adjusted.

G OFFSET value adjusted.

B OFFSET value adjusted.

R GAMMA value adjusted.

G GAMMA value adjusted.

B GAMMA value adjusted.

R GAMMA table displayed.

G GAMMA table displayed.

B GAMMA table displayed.

Remarks

Adjustment ended at a value other than 1001.

Range: 0000~0256

Range: 0000~0256

Range: 0000~0256

Range: 0020~0180

Range: 0020~0180

Range: 0020~0180

Lamp error detection

[1] Function

This LCD color TV set is equipped with automatic power-off (lamp error detection) function. This safety
measure serves if the lamp or the lamp circuit gets in trouble.
If by any chance the lamp or the lamp circuit gets in trouble, or if the lamp error detector gets activated for
any other reasons, the following happens.

1

Turn on the power, but it comes off in about 23 seconds. (The power LED indicator at the front of the set
turns from green to red, and it starts flashing in red, repeating on for 250 ms and off for 1 sec.)

2

If the action 

1

 above occurs 5 times in a row, the power fails to turn on. (The power LED indicator starts

flashing in red, repeating on for 250 ms and off for 1 sec.)

[2] Measures

2-1. Turn off the lamp error detector and check the trouble.

With the "MAIN POWER" switch off, hold down the "INPUT SELECT" and "VOL UP" keys and press the
"MAIN POWER" switch. Now the "display process mode" (<K> appears onscreen) gets started. Then
press on any key, and Page 1 of "Display adjustment mode" appears onscreen.
In so doing, the lamp and lamp circuit can be checked for anything unusual.
Also look at the 4th line "L ERR RESET" on Page 1 of "Display adjustment mode" to see if the value is
more than 1. If so, it means a lamp error has been detected.

2-2. Reset the lamp error counter.

When the lamp and lamp circuit have been checked for trouble, reset the lamp error counter.
Using the "CURSOR UP/DOWN" key, move the cursor to the 4th line "L ERR RESET" on Page 1 of
"Display adjustment mode". Using the "CURSOR RIGHT/LEFT" key, select the value of "L ERR RESET".
Now press the "CURSOR UP/DOWN" key, and the counter will be back to 0.

Finally do the performance check and make sure no lamp error is detected.

Display adjustment process   Page 1

Individual display-related parameters 

Reset to 0

SERVICE

→

GRAYLEVEL

   COMBLAS
   VLSBLAS
   L ERR RESET
   LCD
   PATTERN
   SOUND AND FAN
   OTHER
     VER M1.

~~

37HV4
076
077
064
    5

CEEP6

•

List of process adjustment modes (Display)

Process mode contents   Page 0

LCD     Page 1

LCD     Page 2

LCD     Page 3

LCD     Page 4

Others     Page 2

PATTERN     Page 1

SOUND     Page 1

Others     Page 1