Hitachi CMP5000WXJ Service Manual page 91

Input Signal Step
Adjust the black level of Red and Blue
signals to reference with black level
of Green signal
Black level of
Green signal
Video signal
Black level of
Red or Blue signal
Increase three steps of MAT CONT adjustment value of OFFSET-RGB1.
OFFSET mode: Select the RGB 1 mode by top and bottom keys
14
MAT CONT : 1 key
Increase three steps of adjustment value by right and left keys.
Increase two steps of MAT BRIGHT adjustment value of OFFSET-RGB1.
OFFSET mode: Select the RGB 1 mode by top and bottom keys
15
MAT BRIGHT : 2 key
Increase two steps of adjustment value by right and left keys.
Turn ACL SW setting to ON.
INITIALIZE mode
16
ACL SW : 3 key
Select ON by right and left keys.
Input a RGB (PC) signal to INPUT1 or INPUT2.
A signal pattern is only luminance signal such as lamp signal and a STEP signal.
1
And use the signal which black level (0IRE) and gradation can confirm.
• Recommended signal: VESA VGA@60Hz
Turn to standby once, and perform power supply ON with the factory mode once again.
2
MENU → SET → POWER ON
3
Take a trigger of oscilloscope with HD_PLL (3.3Vp-p) of K4805.
Measure the signal waveform of Green signal at K4603, and measure the black level (0IRE) of signal and signal
4
amplitude.
RGB (PC)
AD R LOW adjustment
signal
Measure the black level (0IRE) of Red signal at K4602, and adjust so that the level of AD R LOW to match the black
level (0IRE) of Green signal which measured with step 10 of video signal.
5
Adjustment error: ± 0.05V
OFFSET mode: Select the RGB 1 mode by top and bottom keys
AD R LOW : 9 key
Adjust by right and left keys.
AD R HIGH adjustment
Measure the signal amplitude of Red signal at K4602, and adjust so that the level of AD R HIGH to match the signal
amplitude of Green signal which measured with step 10 of video signal.
6
Adjustment error: ± 0.05V
OFFSET mode: Select the RGB 1 mode by top and bottom keys
AD R HIGH : 6 key
Adjust by right and left keys.
Adjusting Method
Adjust the signal amplitude of Red and Blue
signals to reference with signal amplitude
of Green signal
Green signal
waveform
Red or Blue
signal
Signal amplitude
waveform
of Green signal
Green signal
waveform
Red or Blue
signal
waveform
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