Installation
2.1.7 Yagi antennas
Yagi antennas are directional and have positive gain to the front of the antenna and
negative gain in other directions. You can use the gain to:
Compensate for coaxial cable loss for transmitter unit; and
Increase receiver sensitivity for receiver units.
You should install Yagi antennas with the central beam horizontal and pointed directly
in the transmission direction to benefit from the antenna gain.
Yagi antennas usually have a drain hole on the folded element. You should
position the drain hole at the bottom when installing the antenna.
You can install Yagi antennas to be either:
NOTE
Vertically polarised – with the elements in a vertical plane; or
Horizontally polarised – with the elements in a horizontal plane.
If both stations are using Yagi antenna we recommend using horizontal polarisation. If
you are using a Yagi antenna to communicate with a Dipole or Collinear antenna we
recommend using vertical polarisation.
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