GME PG-28, Руководство пользователя

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RASTER (Red) RASTER (Blue) RASTER (Black)
COLOR BARS
Eight equal width vertical color bars are displayed at 100% amplitude, 100% saturation in the
order from left to right: White, Yellow, Cyan, Green, Magenta, Red, Blue, and Black.
The COLOR BARS video pattern serves as the fundamental pattern used for most testing,
troubleshooting and adjustments in video equipment. Use this test pattern to check and test
the video device’s ability to produce fully saturated primary and secondary colors. It is often
used as the reference for color adjustment and compensation. When troubleshooting, analysis
of the colors bars pattern helps television service personnel to pinpoint color related problem
to specific circuits. This pattern can also be use as a reference for troubleshooting color
amplifier or color demodulator problems inside the display device.
CROSS HATCH & DOT
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This pattern displays a series of horizontal and vertical straight white lines that forms a grid
of 16 x 12 squares of the same size.
This pattern is used to check and adjust dynamic convergence of the display. Observe the
horizontal and vertical lines to detect color fringing resulting from misconvergence. An
example that the display is misconverged is when the white lines become separated Red,
Green, and Blue lines. Adjust the display’s RGB convergence control to align the colors to
overlap so the horizontal and vertical lines appear as white lines.
This pattern can also provide a convenient reference for making vertical and horizontal
linearity adjustments. Each square should be the same size.
CROSS HATCH pattern is also useful for checking pincushion (bow) distortion and display
geometry such as picture centering, size, and trapezoid (keystone) correction. For trapezoid
correction, adjust the TV’s display control so that the pattern’s edges are parallel to the edges
of the display screen. For pincushion correction, the horizontal and vertical lines should be
adjusted to be straight.