Sharp LC-30AA1H, Service Manual

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LC-30AA1M
LC-30AA1H
5. Adjustment
5-1.VLS BIAS (13V) voltage adjustment (R4231)
Connect a digital volt meter to TL4122 (or C4180+) on the LCD Control PWB and make a adjustment with
the R4231 so that the voltage becomes 13.00V±0.05V.
5-2.COM BIAS adjustment
Shift to the "COM BIAS" item with the cursor UP/DOWN key and select a numeric value with the cursor
RIGHT/LEFT key.
Changing the numeric value with the cursor UP/DOWN key will make appear the test pattern. Make an
adjustment so that the flicker near the center of the screen is minimized.
5-3.Background adjustment
Start up the set with the AVC System connected and adjust the background of the monitor.
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Procedure
-1) Display the adjustment screen (200-level gray scale on High side, 48-level gray scale on Low side).
-2) Adjust "R OFFSET", "G OFFSET" and "B OFFSET" so that the 200-level gray scale pattern becomes
normative.
Adjust the chromaticity of the High pattern (in the left portion of the screen) so that x = 0.290 and y =
0.299.
-3) Adjust "R GAMMA", "G GAMMA" and "B GAMMA" so that the 48-level gray scale pattern becomes
normative.
Adjust the chromaticity of the Low pattern (in the right portion of the screen) so that x = 0.276 and y
= 0.278.
The above-mentioned adjustments can be made according to the following procedure.