Canon D78-5382, Service Manual

Page: 55 / 126

2.7 Gain Adjustment [Component]
1. Receive the 16-step gray scale component video signal [480i] with
Video [Y, Cr, Cb]
mode.
2. Enter the service mode.
3. Connect an oscilloscope to test point "
TP505R " (+) and chassis ground (-).
4. Select item no. " 4 " and adjust the amplitude "a" to be minimum by changing the Data
value.
5. Connect an oscilloscope to test point " TP503G " (+) and chassis ground (-).
6. Select item no. " 5 " and adjust the amplitude "a" to be minimum by changing the Data
value.
7. Connect an oscilloscope to test point "
TP501B
" (+) and chassis ground (-).
8. Select item no. "
6
" and adjust the amplitude "a" to be minimum by changing the Data
value.
Fig. 3-6
2.8 Gamma Gain Adjustment [PC]
1. Receive the 16-step gray scale computer signal with
Computer [Analog RGB]
mode.
2. Enter the service mode.
3. Connect an oscilloscope to test point "
TP505R " (+) and chassis ground (-).
4. Select item no. " 13 " and adjust the amplitude "a" to be 4.0 ±0.1V by changing the
Data value.
5. Connect an oscilloscope to test point " TP503G " (+) and chassis ground (-).
6. Select item no. " 14 " and adjust the amplitude "a" to be 4.0 ±0.1V by changing the
Data value.
7. Connect an oscilloscope to test point "
TP501B
" (+) and chassis ground (-).
8. Select item no. "
15
" and adjust the amplitude "a" to be
4.0
±0.1V by changing the
Data value.
Fig. 3-7
(a)
(a)
White Level
Part 3: Adjustment
3-10