Rockwell Automation 6156 Industrial 14 inch CRT Monitors - Manual (Page 18)

Industrial 14” CRT Monitors 18
Publication 6156-2.0
The monitor is factory preset and normally requires no manual
adjustment for vertical or horizontal alignment. However, four
screwdriver adjustable size and position controls are provided to
permit adjustment if it should ever become necessary. Adjust
controls using a non–metallic insulated 1/8” (3mm) flat screwdriver
passed through the hole(s) of the rear cover. With a suitable full
screen image on display, adjust the Vertical Size for a height of 7.5”
and the Horizontal Size for a width of 10.0”. Adjust Vertical and
Horizontal Position controls as necessary to center the image on the
screen.
Degauss
The monitor is equipped with an automatic degaussing system to
remove residual magnetism from the CRT’s shadow mask at
power-up. Degaussing helps keep the screen free of any color
impurities which might otherwise result from magnetism picked up
by the shadow mask from the earth’s magnetic field when the
monitor is moved.
In addition, a degauss push button is provided on the rear panel. This
manual control can be used if color impurities appear on the screen
while the monitor is in operation.
Note: The internal degauss will not prevent color impurities caused
by local magnetic fields. Make certain the monitor’s enclosure is free
of residual magnetism.
Tip: For best results, perform a manual degauss only after allowing
at least 15 minutes to pass following power-up or a previous manual
degauss.
Raster Rotation
A raster rotation allows for corrections to any display misalignment
which might be present as a result of interaction between the monitor
and an external, low level uniform magnetic field, such as the earth’s
magnetic field.
All CRT displays are affected by the earth’s magnetic field and by
similar low level uniform fields. Generally, the effects of such a field
on the display vary with the display’s spatial orientation relative to
the field lines. For, example, when the Bulletin 6156 Industrial
Monitor’s screen is facing West, the effects of the earth’s field are
minimal, but when the screen is rotated toward the North or South
the display itself can exhibit a small amount of rotation, so that its
top and bottom edges are no longer parallel to the edges of the panel.
"