Exalt Installation and Management Guide
s-Series Digital Microwave Radios
26
201511
2008-02-27
Follow the antenna manufacturer‘s instructions for mechanical mounting of the antenna. Ensure that
there is enough room around the antenna for alignment activities (moving the antenna in vertical and
horizontal arcs). Also ensure that there is enough room for proper mounting of the ODU on the back
of a direct-mount antenna or for the flexible waveguide connection to a remotely mounted ODU.
Always mount remote- mount ODUs as close to the antenna as possible to minimize the length and
associated losses of the flexible waveguide.
At this point in the installation process, the antenna mounts are fully secured to the structure, the feed
of the antenna is securely mounted to the antenna (if the feed is a separate assembly), and the azimuth
and elevation adjustments are not completely tightened to allow antenna alignment. It is a good
practice to connect the ODU or flexible waveguide to the antenna connector as early in the process as
possible to reduce the opportunity for debris or moisture to enter either the antenna connector or
waveguide. The ODU and most antennas and waveguides have a piece of tape or cover that should
remain in place until all connections are made. Take extra care if the system is installed during
inclement weather to ensure that no moisture gets inside any connectors at any time.
Now the antenna can be aimed in the general direction required for the link. Use a compass, a
reference bearing, binoculars, or other similar device to point the antenna in the direction of the far-
end radio, and then slightly tighten the azimuth and elevation adjustments so that the antenna
maintains its general position and is safe to be left without additional securing. Refer to the Exalt
white paper,
Antenna Alignment
, for more information on antenna alignment techniques.
Installing the IDU-to-ODU Cable
The IDU-to-ODU cable is typically two or three separate cables separated by lightning arrestors.
Generally, a short male-to-male coaxial cable connects the ODU to the local lightning arrestor, which
must be properly grounded. The primary cable runs from the ODU lightning arrestor to the egress
point, where another lightning arrestor is mounted and grounded. The final cable runs from the egress
point to the IDU. The cables should traverse the exact route provided by the site planner.
If using a direct-mount antenna and ODU, there is often a need for a small excess of cable near the
antenna/ODU to accommodate both the need for extra slack for movement during antenna alignment
and for a drip loop for the cable and the initial cable securing hardware and grounding near the
antenna. The cable can be very stiff and can provide undue pulling force on the ODU connector.
Ensure that you align the cable with the connector not placing any torque or strain on the connector.
Consult your cable manufacturer for the proper transportation, hoisting, securing, and grounding
process. Always ensure that the entire length of cable never twists, kinks, or gets over-bent beyond
the specified bend radius. Once a cable is over-bent or kinked, it may never recover its specified
characteristics even after straightening, and may become unusable.
As soon as practical, weatherproof the connected ends of the cable to the ODU and the lightning
arrestors. Test the IDU-to-ODU connection prior to installing weatherproofing.
For the indoor cable run, a cable ladder or tray may be needed to secure the cable. In some cases, a
short flexible jumper allows ease of connection to the IDU
TO ODU
connector. A properly specified
90º connector can often eliminate this requirement. Ensure that there is enough space around the radio
to accommodate a gentle bend radius in the transmission line for a good direct connection. In all cases,
ensure that the cable is not applying any pulling force on the
TO ODU
connector on the IDU. Cables
can be very stiff and can damage the connector if not dressed properly. Follow the cable
manufacturer‘s instructions for the proper use of cable securing devices.
Summary of Contents for EX-11s
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