When a signal radiates from a fault in
the cable, it propagates in a pattern of
waves. As the signal’s strength
increases and decreases along the
wave, the level of the wave will rise
and fall. The field technician should
remember that wave fluctuations do
not indicate the existence of multiple
leakage points in the cable.
The ability to accurately detect leak-
age levels can only be achieved
through knowledge of RF signals and
through field experience. The field
technician should have a general
understanding of how RF frequency
reacts in the environment when
released from a cable source. The list
provided below give examples of how
leakage detection can be deceptive to
the experienced and inexperienced
technician.
• A large leak can mask a smaller
one (troubleshoot one leak at a
time).
• Leaks may radiate from the true
source down the cable, strand
and down guys.
• Radio signals may bounce off
buildings and other surfaces cre-
ating false readings.
• A leak may be active one day and
seem to disappear the next day.
• Very strong leaks may overload a
detection meter (use scan or
spectrum mode)
• Metal objects can distort radia-
tion patterns received by your
antenna.
• Sometimes a slight change in posi-
tion of a damaged cable or connec-
tor will cause leaks to subside.
Consequently, the leak source
must still be found and fixed
because it will undoubtedly return.
2-2
~ Common Leakage Sources
Your first step toward locating a
potential leakage site is to combine
common sense with knowing where to
look. Leakage can occur at any point
in a cable system, but the experienced
technician is able to pinpoint a general
location by following the cable or visu-
ally recognizing typical cable egress
indicators. Once the general area of a
leak is identified, the field technician
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