BIRD SITE ANALYZER SA-1700EX, Руководство по эксплуатации

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Maintenance
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Appendix
This appendix provides general information about the
Site Analyzer including term definitions, fault location
equations, and fault location distance tables.
Definitions
Measure Match Mode
The Match Measurement mode shows the resonant
frequencies for an antenna or filter. It also confirms
that there are no impedance problems in the nonreso-
nant components such as cables, connectors, lightning
protectors, and jumpers.
Fault Location Mode
The Fault Location mode shows the location of any
problems in the antenna system. This is shown in
either feet or meters from the cable end connected to
the Site Analyzer.
Cable Loss Mode
The Cable Loss mode shows the insertion loss of a
coaxial cable. By comparing this with the manufac-
turer’s specs, it confirms that there are no problems
with the cable.
VSWR
VSWR units used to be the preferred way to measure
an antenna system. A good antenna has a VSWR of
less than 1.5:1 at its operating frequency.
Return Loss
Return Loss measures, in dB, how much of a wave is
reflected back to the source. It is now the preferred
method for measuring antenna systems. A good
antenna will have a return loss of –14 dB or less at the
operating frequency. The more negative the reading,
the better the antenna.