Hall Research UV1-CV - Manual (Page 10)

Miniature VGA over CAT5 Extension System
8
Figure 3.1
When using a long cable with no compensation, any solid horizontal lines tend to
smear to the right. For example in the image shown, observe the dark black line at
the bottom of the window and see how it is smearing to the right (not changing to
white abruptly as it should). This is the effect of long cable on the signal.
You can turn the trim-pot to
eliminate these streaks as shown on
the second picture. If you add too
much compensation to the signal,
then an opposite effect may be
observed, i.e. black lines smear to
the right as white lines or vice-versa.
The third picture shows the case
where too much compensation is
added.
In general, when using long cables,
the image quality is a function of
resolution and refresh rate. If
possible, set the refresh rate to 60
Hz at any resolution.
Also for best results at long
distances, try to use standard
Category-5 Cable (instead of CAT5e
or CAT6 since CAT5e and CAT6
cables may have widely dissimilar
twist ratios of the wire pairs in the
cable that may result in noticeable
color skew).
No-Compensation
Too much Compensation
Perfect Compensation