Raster Position Adjustment; Flicker Adjustment; Ghost Adjustment; Nrsh Adjustment - Hitachi 50VS69A Service Manual

Final ASSEMBLY ADJUSTMENT

2-3 RASTER POSITION ADJUSTMENT

(1) Receive a static and symmetric image (Circle pattern signal).
(2) Recall Adjustment menu.
(3) Select 'V POSITION' by using the cursor stick (▲/▼ direction)
on handset. Adjust the vertical picture position where |E-F| <= 3mm
by using the cursor stick (
(4) Select 'H POSITION' by using the cursor stick (▲/▼ direction)
on handset. Adjust the horizontal picture position where |G-H| <= 3mm
by using the cursor stick (
NOTE : Refer to page 48 for display area spec.
2-4 FLICKER ADJUSTMEN T
ADJUSTMENT PROCEDURE
(1) SIGNAL: Internal signal from IC (50% raster signal with one dot
black lines)
(2) Red FLICKER ADJUSTMENT:
LCD ADJUST MODE
VCOM R xx
VCOM G xx
VCOM B xx
Press SELECT key, test pattern will be displayed.
Reduce the flicker by pressing cursor stick ◄► of handset.
The adjustment point is the weakest FLICKER position.
(3) GREEN FLICKER ADJUSTMENT:
to the "LCD ADJUST MODE". Select VCOM G and adjust by
same procedure as red flicker.
(4) BLUE FLICKER ADJUSTMENT:
to the "LCD ADJUST MODE". Select VCOM B and adjust by
same procedure as red flicker
Graphic representation of adjustment:
A djustment point
BACK TO ADJUSTMENTS
◄/►
direction).
◄/►
direction).
G
E
F
LCD ADJUST MODE → V.COM .
Press SELECT key to return
Press SELECT key to return
Adjustment range
ADJ.value

2-5 GHOST ADJUSTMENT

ADJUSTMENT PROCEDURE
(1) ADJ.SIGNAL Internal signal from IC (Black window pattern
with RGB raster signal)
(2) RED GHOST LCD ADJUST MODE → GHOST
ADJUSTMENT
LCD ADJUST MODE
GHOST R xx
GHOST G xx
GHOST B xx
Press SELECT key, test pattern will be displayed.
(3) Increase the I
H
until ghost appears at left side of the window pattern.
(4) Then, decrease the I
handset until ghost disappears.
(5) Finally, decrease the I
Example
(6) GREEN GHOST Press SELECT key to return to the "LCD ADJUST MODE".
ADJUSTMENT Select GHOST G and adjust same procedure as red GHOST.
(7) BLUE GHOST Press SELECT key to return to the "LCD ADJUST MODE".
ADJUSTMENT Select GHOST B and adjust same procedure as red GHOST

2-6 NRSH ADJUSTMENT

ADJUSTMENT PROCEDURE
(1) Complete FLICKER ADJUSTMENT before the adjustment.
(2) SIGNAL Internal signal from IC (Gray scale)
(3) Red NRSH ADJUSTMENT LCD ADJUST MODE → NRSH
Press SELECT key, test pattern will be displayed.
Reduce the vertical lines (12 dot width) by pressing the cursor
stick◄► of handset.
Press SELECT key to return to the "LCD ADJUST MODE".
(4) GREEN NRSH ADJUSTMENT Press "▼" of handset. The test pattern
will be changed from red to green.
Adjust the Green NRSH with same procedure as Red NRSH.
The Blue NRSH adjustment is not required.
(5) CHECK FLICKER Check that picture is not flickering. If there is,
re-adjust flicker.
42
2
C data by pressing cursor stick ► of handset
2 C data by pressing cursor stick ◄ of
2 C data by 3 steps
GHOST
GHOST data 10 11 12
-3 step -2 step -1 step Ghost
disappears
(3)
ADJUSTMENT POINT
LCD ADJUST MODE
NRSH HR xx
NRSH HG xx
LC67
.
(1)
13 14
Ghost
appears
(2)