KVH Industries FB250, Installation Manual

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Chapter 2: Installing the system
8 Placing the antenna
2.2 Placing the antenna
2.2.1 Obstructions
The antenna rotates 360° and down to –25° for the TracPhone FB500 and
-60° for the TracPhone FB250 in pitch and roll, to allow for continuous
pointing even in heavy sea conditions. Any obstructions within this volume
can cause signal degradation.
The amount of degradation depends on the size of the obstruction and the
distance from the antenna. As a rule of thumb any obstruction that covers an
angle of less than 3° at the antenna has limited effect. The table below gives a
guideline for obstruction sizes that will cause limited degradation.
Distance of Obstruction Size of Obstruction
3 m 16 cm
5 m 26 cm
10 m 52 cm
20 m 104 cm