LG 32LC6D (CHASSIS:LA75C) Service Manual ▷ View online
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factory mode will reach this basic requirement. The detail calibration method is shown at
section 1.4.1. After signal calibration, we can go to next step, color temperature alignment.
The default calibration values are as below
AV-CVBS NTSC
Tuner-CVBS NTSC
Contrast 134 156
Brightness 33
15
Saturation 173 209
Hue 128
128
Component NTSC
PC 1024x768@60Hz
Digital R Gain
642
702
Digital G Gain
636
700
Digital B Gain
643
708
Digital R Offset
1741
2033
Digital G Offset
2010
2033
Digital B Offset
1741
2033
Analog R Gain
0
0
Analog G Gain
0
0
Analog B Gain
0
0
Analog R Offset
240
128
Analog G Offset
192
128
Analog B Offset
240
128
Below are basic concepts of adjusting RGB gain/offset that can meet spec requirement. When
tuning white balance (color temperature), we manually adjust R, G and B gain and offset by
following below rules to satisfy spec requirement.
x
y
Red gain
↓ x
↓ -
Green gain
↓ - y
↓
Blue gain
↓ x
↑ y
↑
Red offset
↑ x
↑ -
Green offset
↑
- y
↑
Blue offset
↑ x
↓ y
↓
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Suggestion is not to adjust Green gain and offset, both will affect luminance and Gamma. We
adjust Red and Blue gain to check 85% white to see if it is within spec. Eventually the settings
of RGB gain/offset will converge to satisfy spec.
c) Maximum Luminance
After color temperature alignment, the maximum luminance should be greater than 360cd/m².
Condition:
Measurement Point: Center of screen
Measurement Distance: 50mm
Measurement Angle: 90 degree
Contrast: max (100)
Brightness: max (100)
Backlight: max (100)
Others: default
6.1.4 Alignment procedure in FA out processing
6.1.4.1 ADC Calibration
- In factory mode, choose “Factory Reset”
ĺ “Reset All NVRAM Setting”.
- Set Picture mode at Dynamic.
Using AV1-CVBS NTSC with Color Bar white 75% signal
a) Select input source AV1 of operation unit and plug in CVBS cable NTSC with Color Bar
signal (Astro PG1 Timing968, Pattern968).
b) Press first item in factory menu “Auto Calibration”
ĺ “Calibrate Video” to execute
calibration. (See picture 5~6)
c) The signal level from equipment (without any load) show as picture 7.
Picture 5 Picture 6
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Picture 7
Using PC 1024X768@60Hz with 16 Gray Level signal
a) Select input source PC of operation unit and plug in PC cable 1024x768@60Hz with 16
Gray Level signal (Astro PG1 Timing856, Pattern921).
b) Press first item in factory menu “Auto Calibration”
ĺ “Calibrate PC” to execute calibration.
(see picture 8~9)
c) The signal level show as picture 10-1~10-3. (respective R, G and B signals)
Picture 8 Picture 9
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Picture 10-1
Picture 10-2
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