User's Manual

Exalt Installation and Management Guide
EX-i Series (TDD) Digital Microwave Radios
206501-019 31
2016-05-24
line showing that the loss characteristics and VSWR are within the specified limits specifically at your
operating frequency. In addition to factory-built transmission line, self-terminated transmission line can
suffer the same issues.
The manufacturers of transmission line typically offer instruction and certification for transmission line
termination, and may also provide videos illustrating the process. There is no amount of extra care,
education, precision, and effort that can be overstated for this process.
Once the transmission line is connected to the antenna, traverse the exact route provided by the site
planner. There is often a need for a small excess of transmission line near the antenna to accommodate
both the need for extra slack as the antenna is loosened and moved for the alignment process, and to
accommodate a drip loop for the transmission line and the initial transmission line securing hardware
and grounding near the antenna. In addition, the transmission line is typically very stiff, and can provide
undue pulling force on the antenna connector. Take care to align the cable with the connector so that it
does not provide any torque or strain on the connector.
Consult your transmission line manufacturer for the proper transportation, hoisting, securing, and
grounding process. Always be very mindful of the entire length of transmission line to ensure that the
transmission line is never twisted, kinked, or over-bent beyond the specified bend radius. Once a
transmission line is over-bent or kinked, it will likely never recover its specified characteristics, even
after straightening, and will often be completely unusable.
The opposite end of this primary transmission line typically terminates at the building or enclosure
egress point. This is where to locate the RF lightning arrestor. Ensure that a proper termination to the
connector-type of the lightning arrestor is made at this location. A drip loop may be required and proper
securing hardware and grounding must be accommodated.
As soon as practical, weatherproof the connected ends of the transmission line to the antenna and
lightning arrestor. This process should be delayed as long as possible to ensure that all systems are
working properly before applying the weatherproofing. Once weatherproofing is applied, it may have
to be removed for testing or installation modification. With this in mind, if the installation is occurring
during inclement weather, take extra care at all times to ensure that no moisture enters any connector at
any time. If moisture is suspected to have compromised the antenna or transmission line, it may render
those devices useless without any means for remedy except for full replacement.
Indoor Mounting
On rare occasions the antenna can be mounted indoors behind a window. In these cases, there would
not be a need for drip loops or an RF lightning arrestor. Use a very short transmission line connected
directly between the antenna and the radio mounted nearby. The weatherproofing process can also be
omitted.
RF Lightning Arrestor
RF lightning arrestors provide a direct path to ground for lightning strikes that may couple to or directly
hit the outdoor transmission system or antenna structure. The RF lightning arrestor prevents any
associated voltage and current from entering the building or enclosure, where it might harm the radio
equipment, other equipment, or humans.
The following lightning arrestors are examples of proper devices for Exalt Digital Microwave Radios:
Caution! Always follow the manufacturer’s termination process EXACTLY, and only use
the manufacturer’s authorized tools and connectors for a given transmission line type.