SHARP LC27k6
Service Manual

Note: The white balance adjustment should be made in the mode of �Nature� picture. 2.2.1 EPROM Initialization Enter the first page of factory menu, push �ENTER� key after the selecting Clear EEPROM, shut off the power supply after the appearance of �OK�. 2.2.2 VGA and DV1 channels adjustment 2.2.2.1 VGA channel mode preset Input VGA signal of K-7253(PATTERN 5:Final Test),select TIME301 (640*350/70Hz), push �AUTO� key to automatically adjust to make the picture full of the screen, same, to automatically adjust respectively 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), and TIME339 (1280*1024/60Hz). 2.2.2.2 ADC adjustment of VGA channel Input the signal of 64 grades of grey density to K-7253 TIME311, PATTERN474, set the adc-gain to max.(Not exceeding 18) so that the brightest two grades are distinguishable. 2.2.2.3. White balance adjustment of VGA and DV1 channels Input the signal of 8 grades of grey density to K-7253 TIME311,PATTERN471, enter the adjustment menu of white balance. Use the white balance to adjust second and seventh grades. Select mode to be 6500K,adjust offset_R, offset_G, offset_B, to adjust the second grade color coordinate to be 313,329 and the brightness to be about 3.5 nit. Adjust gain_R, gain_G, gain_B so that seventh grade color coordinates are 313,329. Adjust offset_R, offset_G, offset_B and gain_R, gain_G, gain_B,again and again until two grads of grey density are all set to 313,329. Select mode to be 9300K,adjust offset_R, offset_G, offset_B,so that the second grade color coordinates are 285,293 and the brightness about 3.5 nit.Adjust gain_R, gain_G, gain_B so that seventh grade color coordinates are 285, 293. Adjust offset_R, offset_G, offset_B and gain_R, gain_G, gain_B, again and again until two grads grey density are all set to 285,293. Select mode to be 12000K.Adjust offset_R, offset_G, offset_B,so that the second grade color coordinates are 270,283 and the brightness about 3.5 nit. Adjust gain_R, gain_G, gain_B, so that the seventh grade color coordinates are 270, 283. Adjust offset_R, offset_G, offset_B and gain_R, gain_G, gain_B, again and again until two grads grey density are all set to 270,283. Notice: The value of gain_R, gain_G, gain_B should not exceed 128, and at least one of the values should be guaranteed to be 128 2.2.3 TV channel adjustment 2.2.3.1 Adjustment of VCO, OPTION, sub-brightness and sub-contrast Input the AV color bar signal(PM5518 COLOUR BAR 100%)to VIDEO 1 terminal, enter the first page of factory menu. Select auto color, push key �ENTER�. About two seconds later, OK is displayed, showing the adjustment is over. Adjust the value of Option to be 11,S-bright to be 124,S-contrast to be 140, and Max Volume to be 30. 2.2.3.2 White balance adjustment of TV channel Input AV signal (PM5518,NTSC system, eight grades of grey density signal), enter the adjustment menu of white balance. Use the white balancer to adjust the second and seventh grades. Adjust offset_R, offset_G, offset_B,so that the second grade color coordinates are 255,240 and the brightness about 3.5 nit. Fix gain_B to be 128, adjust gain_R, gain_G, so that the seventh grade color coordinates are 290, 285. Adjust offset_R, offset_G, offset_B and gain_R, gain_G again and again until two grads of grey

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