Sony VPH-G90U Service Manual page 90

Adjusting the Registration
3 Green SKEW and BOW adjustments
Adjust the bow-like or skew distortion of the horizontal and vertical center
lines to make them parallel to the screen edges.
A Horizontal line adjustment
If the horizontal line of the picture is as shown by the dotted line in the
illustrations below, adjust it with the corresponding arrow key so that it is
perpendicular to the vertical line (bold line illustrated on the left).
1
Press the BOW key.
The CROSS HAIR pattern appears.
You can also change to the 9 × 9 HATCH pattern by pressing the
PATTERN key.
2
Reset the FINE bow data.
See "Resetting the Data" on page 138.
3
Adjust the distortion as illustrated below with the V and v keys.
4
Press the SKEW key.
5
Reset the FINE skew data.
See "Resetting the Data" on page 138.
6
Adjust the distortion as illustrated below with the V and v keys.
98
Adjustments
V : The left and right ends of the horizontal line curve
upward while the center remains unchanged.
v : The left and right ends of the horizontal line curve
downward while the center remains unchanged.
V : The horizontal line rotates counter-clockwise,
rotating around the center.
v : The horizontal line rotates clockwise, rotating
around the center.
7
Repeat steps 1 to 6 until the horizontal lines become parallel to the
screen edges.
Each time you press the BOW or SKEW key, the COARSE mode and
FINE mode are selected alternately, and you can use the two modes
appropriately. The adjustment data is stored for each mode separately.
While you hold down the arrow key in the FINE mode, "f" is
displayed around the adjustment position.
B Vertical line adjustment
If the vertical line of the picture is as shown by the dotted line in the
illustrations below, adjust it with the corresponding arrow key so that it is
perpendicular to the horizontal line (bold line illustrated on the left).
1
Press the BOW key.
The CROSS HAIR pattern appears.
You can also change to the 9 × 9 HATCH pattern by pressing the
PATTERN key.
2
Adjust the distortion as illustrated below with the B and b keys.
B :The upper and lower ends of the vertical line
curve towards the left while the center remains
unchanged.
b :The upper and lower ends of the vertical line
curve towards the right while the center remains
unchanged.
3
Press the SKEW key.
4
Adjust the distortion as illustrated below with the B and b keys.
B :The vertical line rotates counter-clockwise,
rotating around the center.
b :The vertical line rotates clockwise, rotating around
the center.
5
Repeat steps 1 to 4 until the vertical lines become parallel to the screen
edges.
Each time you press the BOW or SKEW key, the COARSE mode and
FINE mode are selected alternately, and you can use the two modes
appropriately. The adjustment data is stored for each mode separately.
While you hold down the arrow key in the FINE mode, "f" is
displayed around the adjustment position.
99
Adjustments