Chroma Gain Adjustment - Hitachi VM-H675LA Service Manual

6) Refer to display 4-4.
7) VM-H675LA/H675LA(K):
Press 0 (ZERO) C to input the data.
VM-E575LA/E575LA(K)/E573LA/E573LA(K):
Press 0 (ZERO) C to input the data.
VM-H775LE:
Press 1 (ZERO) 6 to input the data.
VM-E578LE(AU)/E578LE(SW)/E575LE:
Press 0 (ZERO) D to input the data.
8) Press [Enter] key.
Perform adjustment according to the computer
displayhereafter.
See "4. Error Messages" if an error message
appears on the computer display.
(3) Chroma Gain Adjustment (Figs. 2-1, 2-2, 2-3)
Purpose:
To set the color saturation under the reference color
temperature.
Incompleted Phenomenon:
Color of the picture is denser than that of the subject.
Color of the picture is lighter than that of the subject.
Equipment/Jig:
Oscilloscope (Vectorscope)
Test Point:
Video Out Jack
Display & Figs
Display 4-1
ADJUSTMENT MENU
***********************************************************
ADJUSTMENT
***********************************************************
[1] AUTO IRIS CONTROL
[2] WHITE BALANCE
[3] CHROMA GAIN
[ESC] RETURN TO MAIN MENU
Please select [1] - [3] or [ESC]
Display 4-4
<< WHITE BALANCE ADJUSTMENT >>
INPUT DATA OF OFFSET FOR Mg-G --> 00
Display 4-5
<< ADJUSTMENT OF CHROMA GAIN >>
ROUGH ADJUSTMENT
[U] CHROMA GAIN UP
[D] CHROMA GAIN DOWN
FINE ADJUSTMENT
[Crt] + [U] CHROMA GAIN UP
[Crt] + [D] CHROMA GAIN DOWN
[ENTER] SAVE & RETURN TO MENU
[ESC] QUIT
3 - 6
Condition:
Procedure:
1) Refer to display 4-1.
2) Press 3 key.
3) Rerer to dispaly 4-5.
4) WhenUsing an Oscilloscope:
5) Press [Enter] key, and the display changes as 4-6 and
6) Press any key to return to ADJUSTMENT MENU
Display 4-6
<< ADJUSTMENT OF CHROMA GAIN >>
DATA WRITING INTO EEPROM
Display 4-7
<< ADJUSTMENT OF CHROMA GAIN >>
ADJUSTMENT FINISHED
PRESS ANY KEY
RED
BURST
100%
Fig. 2-2 [For VM-H675LA/H675LA(K)/
E575LA/E575LA(K)/E573LA/E573LA(K)]
Attach a C12 filter.
Point at a color bar chart.
Press the U and D keys to set the red level to
around 470 mVp-p.
Press the [Ctrl] key and hold it down, then press
the U and D keys so the red level is 470 mV ±
20 mVp-p. (Fig. 2-1)
When Using a Vectorscope:
Press the U and D keys to set the red vector to
around 170 % of the burst.
Press the [Ctrl] key and hold it down, then press
the U and D keys so the red vector is 170 % ± 5 %.
(Figs. 2-2, 2-3)
4-7.
display.
RED
BURST
170%
± 5%
100%
Fig. 2-3 [For VM-H775LE/E578LE(AU)/
E578LE(SW)/E575LE]
470mV
± 20mV
Fig. 2-1
RED
170%
± 5%