Sony GV-A500 Service Manual page 103

10. V-COM Adjustment (PD-88 baord)
Set the DC bias of the common electrode drive signal of LCD display
to the specified value.
If deviated, the LCD display will move, producing flicker and
conspicuous vertical lines.
Mode Playback pause
Signal Alignment tape:
LP mode operation check
(WR5-8NLE (NTSC))
(WR5-8CLE or WR5-4CL (PAL))
Color bar portion
Measurement point
Check on LCD display
Measuring instrument
Adjustment page D
Adjustment address 59
Adjusting method:
1) Set page: 0, address: 01, data: 01.
2) Playback the alignment tape and set to the playback pause mode.
3) Change the data of page: D, address: 59. When the data is
increased from the initial value, vertical lines with intervals of
3 dots between them will be seen. Take the data at this times as
DA. When decreased from the initial value, the same vertical
lines will be seen. Take the data at this times as D
4) Convert D and D to decimal numbers to obtain D
A B
(Refer to Table 5-1-5. "Hexadecimal notation-decimal notation
calculation table".)
5) Calculate D ´ using the following equation (decimal
C
calculation).
D ´ = (D ´ + D ´) ÷ 2
C A B
6) Convert D ´ to hexadecimal number to obtain D
C
7) Set page: D, address: 59, data: D
of the adjusting remote commander.
8) Set page: 0, address: 01, data: 00.
Fig. 5-3-35.
.
B
´ and D
A
.
C
and press the PAUSE button
C
Enlaargement
3 dots between
11. White Balance Adjustment (VC-197 baord)
Correct the white balance.
If deviated, the LCD screen color cannot be reproduced.
Mode
Signal
Measurement point
Measuring instrument
Adjustment page
Adjustment address
Specified value
Note : Check the white balance only when replacing the following
parts. If necessary, adjust them.
1. LCD panel
2. Light induction plate
3. IC801
Adjusting method:
1) Set page: 0, address: 01, data: 01.
2) Check that the LCD screen is not colored. If colored, change
the data of page: D, address: 55 and 56 so that the LCD screen
´.
B is not colored.
Note : To write in the non-volatile memory (EEPROM), press
the PAUSE button of the adjusting remote commander
each time to set the data.
3) Set page: 0, address: 01, data: 00.
5-44
VTR stop
10-step stair-step signal or color bar
signal whose chroma and burst signals
are turned off
Check on LCD screen
D
55, 56
The LCD screen should not be
colored.