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4
(7). Raster Distortion Adjustment
Test Point: Video Monitor Screen
Adjust:
Deflection Magnets
8
Supply Cross-hatch signal from the Video Signal
Generator to the Video Input Connector.
8
Adjust 8 magnets as shown in Fig. 4-3 so that the raster
distortion becomes minimum.
Fig. 4-3
8
The raster distortion against 8 magnets are as shown in
Fig. 4-4.
Fig. 4-4
(8). Centering and Horizontal Width Fine
Adjustment
Test Point: Video Monitor Screen
Adjust:
Centering Magnets
L304 (H-WIDTH)
Main Board
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust the Centering Magnets (See Fig. 4-1.) until the
raster becomes to the center of the monitor screen.
8
Adjust L304 so that the full Horizontal Width becomes plus
6 % ± 1 % overscanning.
8
Repeat adjusting the Centering Magnets and L304 until
satisfactory.
(9). Vertical Height and Vertical Linearity Fine
Adjustment
Test Point: Video Monitor Screen
Adjust:
VR202 (V-HEIGHT)
Main Board
VR204 (V-LIN)
Main Board
VR205 (SUB V-HEIGHT)
Main Board
Centering Magnets
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust VR202 so that the full Vertical Height becomes plus
6 % ± 2 % overscanning.
8
Adjust VR204 so that the circle portion of the Monoscope
pattern becomes nearly a true circle.
8
Adjust the Centering Magnets so that the Monoscope
pattern comes to the center of the monitor screen.
8
Repeat adjusting VR202, VR204 and the Centering
Magnets until satisfactory.
8
Set the TV Standard Selector (CCIR/EIA) to EIA position.
8
Adjust VR205 so that the proportion of the height of the
circle to the width becomes 1.25 as shown in Fig. 4-5.
Fig. 4-5
8
Set the TV Standard Selector (CCIR/EIA) to CCIR
position.
(10). Focus Adjustment
Test Point: Video Monitor Screen
Adjust:
VR104 (FOCUS)
CRT Board
8
Supply Monoscope pattern signal from the Video Signal
Generator to the Video Input Connector.
8
Adjust VR104 for best focus in the monitor screen.
600
1100
50
550
40
35
30
25
20
15
10
5
40 35 30 25 20 15 10 5
4
4
3
8
8
10
6
6
4
3
2
4
5
6
3
525 LINE
20
10
15
5
20
10
15
5
20
10
15
5
20
10
15
5
30
5
5
10 15
8
30
5
5
10 15
8
30
5
5
10
15
8
30
5
5
10
15
8
4
4
4
5
3
3
2
3
1
1.25
Width : Height = 1 : 1.25
Adjust eight magnets.
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