Sharp LC-19SK25U Service Manual page 38

LC-19SK25U/U-W
LC-19SB25U/U-W
LC-19SB15U
LC-19D45U
3.5.3 Common bias Adjustment
1 Feed in built-in signal (See follow picture)
2 Adjust the "COM BIAS" setting so that the peak-to-peak of the wave be minimized.
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