Campbell Scientific RF401A-Series Spread Spectrum Radios - Manual (Page 27)

RF401A-Series Spread Spectrum Radio
directional antenna may make a significant difference. Keep in mind that
commercial tower sites and urban areas tend to evolve over time meaning that
sources of interference may develop over time.
10.2 Antenna Selection, Placement, and Mounting
Antenna selection and placement can play a large role in system performance.
Often directional antennas are preferred over omnidirectional antennas when
possible as RF energy can be more selectively directed and received and higher
gains can be realized without the consumption of additional power.
Additionally, a good rule of thumb is to place antennas as high as possible.
Giving an antenna a higher elevation often increases the amount of area and
distance it can “see” and cover with “line of sight”. Sometimes performance
can be improved by even slightly changing the horizontal or vertical position of
the antenna.
10.3 Antenna Cables
• Routing
o Route all conductors and cables in a neat, orderly fashion. Avoid
routing directly over or across system components.
o Avoid routing conductors carrying low level analog signals in close
proximity and parallel to conductors carrying digital signals or
switched voltage levels.
• Bend Radius
o The RF cable used to interconnect the radio and antenna has a
specified minimum bend radius. Exceeding it will lead to a
degradation of system performance: extra losses, high VSWR, etc.
• Strain Relief
o Avoid cable chaffing and connector fatigue by strain relieving all
conductors and cables that span a distance of more than 12 inches or
have a potential for relative motion due to vibration or wind.
• Connectors
o All exposed RF connectors should be weatherproofed. A good
method is to apply overlapping wraps of a good quality mastic tape,
extending several inches beyond either side of the connection, then
cover the mastic tape with tight, overlapping wraps of a good quality
vinyl tape.
o Maintain electrical connectors in a clean, corrosion-free condition by
means of a periodic application of a good quality aerosol-based
contact cleaner.
11. Operation
The following settings are available for the RF401A-series radios. Configure
them as appropriate for your application.
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