XOCECO LC23K6, Service Manual

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3.1 EEPROM initialization
Enter the first page of factory menu, select “clear eeprom” and then press “enter”, shut down the
unit after “ok” appears.
3.2 VGA/DVI channel adjustment
3.2.1 Preset VGA channel mode
Input VGA signal (PATTERN 5: Final Test) of K-7253, select TIME301(640*350/70Hz), press
“AUTO” to do the auto adjustment until the screen is filled with picture. Use the same method to do
auto adjustment for the following items:
TIME302 (720*400/70Hz) TIME303 (640*480/60Hz) TIME311 (800*600/60Hz)
TIME313 (1024*768/60Hz) TIME315 (640*480/75Hz) TIME316 (800*600/75Hz)
TIME317 (1024*768/75Hz) TIME319 (1280*1024/75Hz) TIME339 (1280*1024/60Hz)
3.2.2 ADC adjustment of VGA channel
Input K-7253 64 level gray-scale signal of TIME311 and PATTERN474, adjust ADC-gain to its
maximal (not above 18) to let the brightest two levels can be recognized.
3.2.3 White balance adjustment VGA/DVI channel
Input K-7253 64 level gray-scale signal of TIME311 and PATTERN474, enter white balance
adjustment menu; adjust the third and seventh levels using white balance.
Select 6500k of “mode”, adjustment offset_R, offset_G and offset_B, let the color coordinate of the
third level be 308 and 316 and its brightness be 12.5nit more or less. Adjust gain_R, gain_G and
gain_B, let the color coordinate of seventh level be 308 and 316.Adjustment offset_R, offset_G,
offset_B, gain_R, gain_G and gain_B repeatedly until the value of the two levels gray-scale be 308
and 316.
Select 9300k of “mode”, adjustment offset_R,offset_G and offset_B,let the color coordinate of the
third level be 285 and 290 and its brightness be 12.5nit more or less. Adjust gain_R,gain_G and
gain_B, let the color coordinate of seventh level be 285 and 295.
Select 12000k of “mode”, adjustment offset_R, offset_G and offset_B, let the color coordinate of the
third level be 270 and 283 and its brightness be 12.5nit more or less. Adjustment offset_R, offset_G,
offset_B, gain_R, gain_G and gain_B repeatedly until the value of the two levels gray-scale be 270
and 283.
Note: gain_R, gain_G, gain_B is value not above 128 and let its value 128 at least
.
3.3 Adjustment TV channel
3.3.1 Adjustment VCO, OPTION, sub-brightness and sub-contrast
input AV color bar signal(PM5518 COLOR BAR 100%) to VIDEO 1 terminal,enter the first page of
factory menu, press “enter” selecting “auto color” display “OK” after 2 seconds, then you can finish
the VCO adjustment; set the value of “option” to 9 and s-bright to 150 as well as S-contrast to 140.
set the MaxVolume according to its product standard. Set value of page VPC3230 to 0,0,3,3,3,3,0.
3.3.2 white balance adjustment of TV channel
Input AV signal (PM5518, NTSC system, 8 level gray-scale signal), enter adjustment menu of white
balance, adjust the third level and seventh level using white balance. Adjust offset_R, offset_G and
offset_B to let color coordinate of the third level be 285 and 290 and its brightness be about 12.5nit.
fixate gain_B, adjust gain_R, gain_G to color coordinate of the seventh level be 285 and 290. adjust