WeatherHawk 240 Signature Wireless Weather Station - Manual (Page 6)

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Wireless Communications
Transmission Ranges
Site your WeatherHawk within the spread spectrum radio transmission range. Typical line-of-sight (LOS)
transmission ranges are listed below:
Up to ½ mile (0.8 km)for the WeatherHawk 916/922/520/521
Up to ¼ mile (0.4 km)for the WeatherHawk 240
Up to 7 miles if optional higher gain antennas are installed on both the WeatherHawk station and
the RF4xx Base Station
a. The transmission ranges assume standard WeatherHawk antennas are used at the computer
site. User-supplied, higher gain antennas at the base station and/or on the WeatherHawk can
effect the transmission range.
b. The ranges assume no obstructions are in the line-of-sight. Line-of-sight is defined and
described below.
Line-of-Sight
Line-of-sight is defined as a straight path between a transmitting and receiving antenna that is unobstructed
by intermediate topography or obstructions (see Figure 2). A clear line-of-sight is required to achieve the
optimum transmission range. The affect of obstructions on the transmission range can vary. Therefore if
obstructions lie within the line-of-sight, you should test your radio transmissions before permanently
installing your WeatherHawk station (see Testing Radio Transmissions on next page).
Figure 2: Line-of-sight examples. As the dotted line indicates, Station 1 has a clear line-of-sight with
the Computer Site. The mountain obstructs Station 2’s line-of-sight and would attenuate the RF signal
or prevent wireless communications completely.
Station 1
Station 2
Computer Site