White Balance Adjustment - Hitachi C47-WD7000 Service Manual

SERVICE ADJUSTMENTS

2.16 WHITE BALANCE ADJUSTMENT

2.16.1 CHECK CUT OFF ADJUSTMENT
Adjustment preparation
Pre heat-run should be finished.
Adjustment procedure
(1) Go to "SERVICE item No10" and press [►] key to enter CUT OFF adjustment mode by using JIG R/C.
(2) Check the each line is just appearing.
(3) If some of line is/are brighter/darker than others, apply CUT OFF ADJUSTMENT again.
(4) Press [◄] key to return to normal mode.
2.16.2 WHITE BALANCE ADJUSTMENT
High brightness white balance
Service Item
Red : (R DRV)
Green: (G DRV)
Adjustment preparation
(1) Pre-heat 20 minutes or more before the adjustment.
(2) VIDEO control should be set Factory Preset condition.
(Contrast : MAX., others : center)
(3) Color temp. : COOL
(4) Signal (COMPONENT INPUT should be used in order to reduced digital noise.)
High Light white balance ADJ
Low Light white balance ADJ
* Use signal without color burst. If it is not possible, use PAL signal and turn off comb filter in User Menu.
(5) BLUE defocus ADJ. should be finished.
(6) The vertical incident illumination on the screen should be 20 Lux. or less.
Adjustment procedure
A) High Light W/B adjustment:
(1) Receive signal for High Light white balance ADJ.
(2) Adjust the white balance to below Data at the screen
White Balance Data
center by using JIG R/C. Use item No. 43(R DRV) to adjust x, item No 44 (G DRV)
to adjust y.
B) Low Light W/B adjustment
(1) Receive signal for Low Light white balance ADJ.
(2) Adjust the white balance to below Data by using R/C
White Balance Data
Use item No.45 (R CUT OFF) to adjust x, item No.47 (B CUT OFF) to adjust x AND y.
Do NOT change the item No.46(G CUT OFF) setting.
Repeat A & B two or three times.
Item No.
43
44
SIGNAL
WHOLE WHITE 100 IRE
WHOLE WHITE 25 IRE
High Light W/B
(x, y) = (0.266, 0.270)
Low Light W/B
(x, y) = (0.266,0.270)
63
Sub Brightness should be adjusted roughly
Before adjust the white balance.
Low brightness white balance
Service Item
Red : (R cut OFF)
Green: (G cut OFF)
Blue : (B cut OFF)
Item No.
45
46
47