Skew adjustment – Adder Technology X2 User Manual
Page 22
21
Skew adjustment
The twisted pair cabling supported by the X2 Multi Screen modules (category 5,
or higher) consists of four pairs of wires per cable. Three of these pairs are used
by the modules to convey red, green and blue
video signals to the remote video monitor. Due
to the slight difference in twist rate between
these three pairs, the red, green and blue video
signals may not arrive at precisely the same time.
This is visible as separate colour shadows on high
contrast screen images. This effect is particularly
apparent when using higher screen resolutions
and some types of category 5e cables.
In this situation, the modules provide internal
skew adjustment that can help to rectify the
situation. The skew adjustment works by
delaying or advancing the timing of any of the red, green or blue colour signals
so that they are all delivered to the monitor at precisely the same time. For best
results a test pattern is provided and this should be displayed when using skew
adjustment.
Convergence test
pattern showing the
RGB crosses. In this
case, the green signal
can be seen out of
line with the other
two colours.
1 2 3 4 5 6 7 8
8
6
5
2
8
6
5
2
Data signal
Red
video signal
Green
video signal
Blue
video signal
7
3
4
1
7
3
4
1
To use skew adjustment
1 Insert the supplied Adder Installation CD-ROM into the CD player of the
computer.
2 Within Windows, use the My Computer
option (usually available as a desktop icon
or within the Start menu) to view the
contents of the CD-ROM. Double-click
the
Skew entry to display the standard
test pattern. If necessary, maximise the
application window so that the image fills
the screen.
The screen will show a series of fine red,
green and blue crosses which should all be
in line, vertically and horizontally. Skew affects the horizontal placement of
the colours and using this pattern it is much easier to discover which, if any,
colours are being adversely affected by the twisted pair cable run.
continued on next page