Triplett CableRater- PN: 3279 - Manual (Page 17)

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Coaxial cable, however, always has increasing Loss as frequency increases. This
effect must be considered, and compensated for if necessary. Various methods
of compensation are available... like amplifiers with frequency ‘tilt’ adjustments,
or inline tilt compensators. Tilt compensation is often used when cable runs
exceed several hundred feet.
Important Note:
Occasionally, the CableRater may indicate that a longer cable has less Loss. This
is possible if the longer cable in question is made with premium materials and
superior construction techniques. However, if the cable is less than 30ft long, its
more likely that the CableRater is “lying”. “Standing Waves” can occur when
measuring the cable Loss. These Standing Waves in the cable can make the
Loss appear to be a little higher or lower than it really is. Usually, the effect
causes less than 2dB of error in the measurement, often less than a few tenths
of a dB of error.
If a measurement indicates that several cables of slightly different length (for
example 10, 11, and 12ft) show losses that seem contradictory to their length,
the likely cause is Standing Waves. This is a well documented phenomenon, and
not a reason for concern (i.e. the cables are not bad).
9.6 Testing Loss in a Splitter
Splitters are used to ‘split’ one Cable TV signal into multiple signals. They are
manufactured in different shapes and sizes, and are commonly available to split
the signal in as many as 16 ways. When the signal is split, the resulting multiple
signals are lower in level than the original signal. The splitters have Loss. In
general, the Loss for all types of splitters is about the same for a given number
of outputs. Figure 7 shows some typical Losses experienced by splitters with
different numbers of outputs.
e p y T r e t t i l p S B d n i s s o L
y a w 2 5 . 3
y a w 3 5 . 5
y a w 4 7
y a w 6 9
y a w 8 1 1
y a w 6 1 6 1
Figure 7
Typical Splitter Losses