NEC MultiSync FP1370 Service Manual page 56

6-4. Cut off Adjustment
1) Receive signal 23 All black
2) Open Menu (S), TAG8 "SUB BIAS" and push "RESET" SW.
Note: Do not touch a front panel key and do not come out from "SUB BIAS" since a picture can not be seen.
3) Connect the DVM with a high voltage probe at TP-G2 on the CRT PWB and adjust SCREEN
SAFTY
VR to obtain 700 Vdc ± 5 Vdc. (Use a high voltmeter whose maximum voltage is more than 1.5kV and
input resistance is more than 1000 MΩ.)
4) Set 00 channel x, y, Y modes of color analyzer CA-100 and make sure that the following values are preset.
x = 0.273
y = 0.300
Y = 0.2 cd/㎡
5) Set analyzer mode at color analyzer.
6) Open Menu (S), TAG8 " SUB BIAS " and adjust until raster appears with "+" and "-" SW.
The color that appears first is the reference color.
Adjust "+","-"SW so that its color analyzer indicated value is 20-80.
If color analyzer does not indicate 20-80, adjust "SUB BIAS" 255 and go to (7).
Then reference color is anything OK.
7) Open Menu (S), TAG8 and adjust the reference color bias so that its analyzer indicated value is 90-110.
8) Open Menu (S), TAG8 and adjust the other color biases so that its analyzer indicated value is 90-110.
9) When the indicated value of the reference color is over 110, repeat steps (7) to (8) so that it is 90-110.
10) Close menu.
6-5. Contrast Tracking Adjustment
1) Receive Signal 23.
2) Open Menu (S), TAG8 "CONT MAX/MIN". Adjust "+" SW so that the contrast is max.
3) Setting modes x, y, Y at the color analyzer, measures the window color temperature. This
measurement determines x=x1, y=y1.
4) Open Menu (S), TAG8 "CONT MAX/MIN". Adjust "-" SW so that the contrast is min.
5) Measure the window color temperature. This measurement determines x=x2, y=y2.
6) Open Menu(S), TAG8 "G BIAS", "R BIAS", "B BIAS" and make sure that the window color
temperature are the following values :
x2 = x1 ± 0.003
7) Open Menu (S), TAG8 "CONT MAX/MIN". Adjust "+" SW so that the contrast is max.
8) Measure the window color and confirm that the readings are the following values :
x1 = x2 ± 0.003
If not, repeat items 3) to 8).
9) Push "EXIT" SW twice.
Signal: No.23 (1600*1200@85Hz) All black
Signal: No.23 (1600*1200@85Hz)
Window Pattern (H: 33% V:33%)
y2 = y1 ± 0.003
y1 = y2 ± 0.003.
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