Black Limit Adjustment (Pk-064 Board); Contrast Adjustment (Pk-064 Board) - Sony Cyber-shot DSC-P71 Service Manual

7. Black Limit Adjustment (PK-064 Board)

Set the maximum amplitude of the RGB decoder for driving the
LCD to the specified value.
If deviated, the LCD screen image will be blackish or saturated
(whitish).
Mode PLAY
Signal Arbitrary
Measurement Point Pin 8 of CN903 (PANEL COM)
Measuring Instrument Oscilloscope
Adjustment Page A
Adjustment Address 86
Specified Value A = 8.30 ± 0.07 Vp-p
Adjusting method:
Order Page Address Data
1 0 01 01
2 A 02 03
3 4 F1 08
4 A 86
5 A 86
Note 1: Adjust it between data 00 and 0F.
Note 2: Check that the adjusted value of D range is within speci-
fied value after this adjustment is performed.
If not, perform the adjustment again.
Processing after Completing Adjustments:
Order Page Address Data
1 A 02 00
2 4 F1 00
3 0 01 00
A
V
Fig. 5-1-20
Procedure
Press PAUSE button
Change the data and set the
voltage (A) to the specified
value. (Note 1)
Press PAUSE button.
Procedure
Press PAUSE button

8. Contrast Adjustment (PK-064 Board)

Set the level of the VIDEO signal for driving the LCD to the speci-
fied value.
If deviated, the LCD screen image will be blackish or saturated
(whitish).
Mode
Signal
Measurement Point
Measuring Instrument
Adjustment Page
Adjustment Address
Specified Value
Adjusting method:
Order Page Address Data
1 0 01
2 A 02
3 4 F1
4 A 8A
5 A 8A
Note: Adjust it between data 00 and 7F.
Processing after Completing Adjustments:
Order Page Address Data
1 A 02
2 4 F1
3 0 01
10 steps peak
A
Pedestal
A: Between the pedestal and 10 steps peak
5-37
DSC-P71/P71M
PLAY
Arbitrary
Pin 9 of CN903 (VG)
External trigger: Pin 8 of CN903
(PANEL COM)
Oscilloscope
A
8A
A = 2.50 ± 0.05 Vp-p
Procedure
01
03 Press PAUSE button
03
Change the data and set the
voltage (A) to the specified
value. (Note)
Press PAUSE button.
Procedure
00 Press PAUSE button
00
00
2H
Fig. 5-1-21