Raymarine QUANTUM 2 Installation Instructions Manual page 31

In systems with multiple MFDs, the Radar should be connected to the MFDs
that are located closest to it, or to the MFDs with the clearest line of sight
to the Radar.
The maximum distance between MFD and Radar will vary depending on the
installation environment (i.e. obstructions and interference).
Example 1 — Open air, line-of-sight in optimum conditions
In optimum open air, clear line-of-sight conditions a reliable connection is
possible at distances up to 100 m (328 ft). However, there are many factors
that can influence this, so a pre-installation site survey should always be
performed. For reliable Wi-Fi performance the signal strength should be
better than –75dBm. The closer the signal is to zero the better the Wi-Fi
performance will be (e.g. –40dBm is better than –75dBm). You can assess
the potential signal strength at the desired location during the Pre-installation
Site Survey using a Wi-Fi Analyzer app on your smart device.
Location requirements
Example 2 — Signal passing through Fiberglass coach roof
In the example above the maximum distance with acceptable Wi-Fi
performance is 15 m (49 ft), due to the heavy fiberglass coach roof that the
signal has to pass through.
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