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3
(2). Horizontal Hold Adjustment
Test Point: Pin 2 of Deflection Coil
Adjust:
VR301 (H-HOLD)
Main Board
8
Disconnect the signal from the Video Signal Generator.
8
Connect the Frequency Counter to Pin 2 of the Deflection
Coil.
8
Adjust VR301 to obtain 15.400 kHz ± 50 Hz.
(3). Picture Tilt Adjustment
Test Point: Video Monitor Screen
Adjust:
Deflection Coil
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Loosen the Deflection Coil Holding Screw as shown in Fig.
4-1.
Fig. 4-1
8
Turn the Deflection Coil until the raster becomes straight
horizontally on the monitor screen.
8
Tighten the Deflection Coil Holding Screw carefully.
(4). Horizontal Width Coarse Adjustment
Test Point: Video Monitor Screen
Adjust:
L304 (H-WIDTH)
Main Board
8
Supply the Monoscope pattern signal to the Video Input
Connector.
8
Adjust L304 so that the full Horizontal Width becomes plus
6 % ± 2 % overscanning.
(5). Vertical Height and Vertical Linearity Coarse
Adjustment
Test Point: Video Monitor Screen
Adjust:
VR202 (V-HEIGHT)
Main Board
VR204 (V-LIN)
Main Board
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
Repeat adjusting VR202 and VR204 until satisfactory.
(6). Sub-Brightness Fine Adjustment
Test Point: Video Monitor Screen
Adjust:
VR101 (CONTRAST)
Main Board
VR102 (BRIGHT)
Main Board
VR103 (SUB BRIGHT)
CRT Board
8
Supply the Stairstep signal to the Video Input Connector.
8
Adjustment should be done after more than five minutes
warm-up.
8
Turn the CONTRAST Control and the BRIGHT Control to
their mechanical center position.
8
Turn VR103 so that the 8th step of the Stairstep signal
becomes cutoff and the 7th step becomes visibly bright as
shown in Fig. 4-2.
Fig. 4-2
8th step becomes cutoff.
7th step becomes visibly bright.
Loosen Deflection Coil Holding Screw.
Centering Magnets
Deflection Coil
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