Hitachi 50VS69A, Service Manual

Page: 46 / 122

III. ASSEMBLED P.W.B. ADJUSTMENT
2-9 Color Uniformity (White Uniformity)
COLOR UNIFORMITY data should not be adjusted. This data are adjusted by the factory
and MEMORY INITialize cannot erase these data. If and only if the customer request to
change the color uniformity, follow the instruction below.
(1) Heat run for 10 minutes or more after power on.
The four white signals generated from the internal IC
(3) Change only the step that are requested to change.
The screen is divided in 25 spaces. It can adjust for 4 different luminance levels. These
data is linearly interpolated on screen.
1. COLOR UNIFORMITY ADJUSTMENT PROCEDURE
Adjustable luminance level is divided in 4 (MIN (8%), MIDL (20%), MIDH (55%), and HMAX
(82%)).
FOR EXAMPLE
If a customer complains about the color uniformity at position 5 on the screen (luminance
level; MIDH), increase the BLUE (or GREEN or RED) value and adjust the color uniformity
of position 5.
I
2
C MENU
LCD ADJ > C.UNIF (MIDH) > POINT No.5
S TORE THE DATA TO TV SET
LCD ADJ > G/C WRITE
-
press for 2
-
3 second
After this procedure, this new data will be written back to E 2 PROM. It takes about 20
seconds.
1 2 3 4 5
6 7 8 9 10
11 12 13 14
15
17 18 19
20
21 22 23 24 25
16
ADJUST
MODE (LCD-PTV)
POINT No.5
R 00 ->increase this data
G 00 ->increase this data
B F7 ->increase this data
05 04 03 02 01 00 FF FE FD FC FB FA F9 F8
increase decrease
center
Final ASSEMBLY ADJUSTMENT
BACK TO ADJUSTMENTS
4
5
LC67