Wells-Gardner D9100 Computer Monitor User Manual


 
7-3.8 Purity and Convergence Adjustment (continued)
Check the purity of the red and blue raster by adjusting the bias
controls.
Obtain a white raster, referring to “CRT GRAY SCALE
ADJUSTMENT”
Proceed with convergence adjustment.
2. Convergence adjustment:
Change to a crosshatch pattern with a color signal generator.
Adjust the BRIGHTNESS and CONTRAST controls for well
defined pattern.
Adjust two tabs of the 4-pole magnets to change the angle between
them and superimpose red and blue vertical
lines in the center of the picture screen.
Turn both tabs at the same time keeping their angles constant to
superimpose red and blue horizontal lines at the center
of the screen.
Adjust two tabs of 6-pole magnets to superimpose red/blue line
with green one. Adjusting the angle affects the vertical
lines and rotating both magnets affects the horizontal
line.
Repeat adjustments 3,4 and 5, keeping in mind red, green
and blue movement, because 4-pole magnets and 6-pole
magnets interact and make dot movement complex.
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