User manual

Chapter Two Installation
Man_805U Rev 1.9 Page 13
2.2.2 Yagi antennas.
A Yagi antenna provides high
gain in the forward direction,
but lower gain in other
directions. This may be used to
compensate for coaxial cable
loss for installations with
marginal radio path.
The Yagi gain also acts on the
receiver, so adding Yagi
antennas at both ends of a link
provides a double improvement.
Yagi antennas are directional.
That is, they have positive gain
to the front of the antenna, but
negative gain in other
directions. Hence Yagi antennas
should be installed with the
central beam horizontal and
must be pointed exactly in the
direction of transmission to
benefit from the gain of the
antenna. The Yagi antennas
may be installed with the
805U
Antenna installed
with drain holes
down
Coax feed looped
at connection
90
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