User's Manual

Trailblazer Installation and User Manual version 1.03
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2.1 Site Requirements and System Planning
2.1.1 Grounding
A ground is a low impedance electrical connection to earth that is used to dissipate
energy. Grounding your Trailblazer is very important for safety reasons as well as to
protect your system from damage due to lightning and static charge build up. Since
lightning strikes and surges follow the path of least resistance, all ground wires must be
as short and straight as possible and not be coiled or looped. Choose the largest
diameter ground wire your ground connectors will accept for good electrical
conductivity.
Recommended grounds are: the utility company ground, a ground rod, well casings,
and cold water pipes that are of continuous metal. A note of caution: sometimes the
metal-cold water pipes are repaired and/or extended with PVC piping hidden behind
drywall. The introduction of PVC material disrupts the material’s conductivity and thus
renders it unacceptable as a ground.
Unacceptable grounds are: sprinkler pipes, PVC pipes, conduit, buried wire, and any
ground that cannot be verified.
2.1.2 Lightning Protection
Lightning protection with a poor ground is the same as having no protection at
all!
Lightning is one of the most dangerous and unfortunately most frequently encountered
natural hazards to your Trailblazer. Ensure that your system is adequately protected. A
good connection to ground is indispensable for your lightning protection to work
correctly and thus preventing lighting and surge damage to your Trailblazer. The
Trailblazer system is equipped with on-board secondary active lightning protection
only. The lightning protection is only effective when the system is powered up. If you
power down your Trailblazer, disconnect the antennas and phone lines to prevent
damage from lightning strikes. Install primary lightning protection with a good ground
on all RF, data/voice line connections that have even a moderate outdoor line build out.
A good rule of thumb is that all lines entering or exiting a building need protection. Both
ends of the cables between buildings must be protected! See section 5.2 for detailed
specifications and usage information on primary lightning protection available from
Carlson Wireless.
2.1.3 Line of Sight: Is it enough?
Visual line of sight (LOS) is the straight, unobstructed line between the Base unit’s
antenna and the CPE’s antenna. In other words, when you stand next to one antenna,
you can see the other one. Because RF waves spread out three dimensionally rather
than in a straight line, LOS is important in microwave transmission but not adequate.
As the waves travel out from the transmitting antenna, the signal density decreases and
more three dimensional space around the visual LOS is necessary to be able to receive