Canon D78-5311, Руководство по обслуживанию

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[G offset adjustment]
6. Connect an oscilloscope to test point "TP25G1" (+) and chassis ground (-).
7. Select item no. "12" of group no. "3" and change data value to adjust it so that
waveform "a" (black signal part) has the maximum amplitude.
[B offset adjustment]
8. Connect an oscilloscope to test point "TP25B1" (+) and chassis ground (-).
9. Select item no. "13" of group no. "3" and change data value to adjust it so that
waveform "a" (black signal part) has the maximum amplitude.
2.9 PC Gain Adjustment
1. Receive the 16-step gray scale computer signal.
2. Set to
COMPUTER mode.
3. Enter the service mode.
[R gain adjustment]
4. Connect an oscilloscope to test point "TP25R1" (+) and chassis ground (-).
5. Select item no. "3" of group no. "2" and change data value to adjust it so that
waveform "a" has the minimum amplitude.
[G gain adjustment]
6. Connect an oscilloscope to test point "TP25G1" (+) and chassis ground (-).
7. Select item no. "4" of group no. "2" and change data value to adjust it so that
waveform "a" has the minimum amplitude.
[B gain adjustment]
8. Connect an oscilloscope to test point "TP25B1" (+) and chassis ground (-).
9. Select item no. "5" of group no. "2" and change data value to adjust it so that
waveform "a" has the minimum amplitude.
Part 3: Adjustment
3-13
Black Level
(a)
Fig. 3-5
White Level
(a)
Fig. 3-6