Panasonic WX-SA250P Operating Instructions Manual page 36

Antenna location
When the area size is equal to the antenna coverage area
When the size of the area is equal to √2 times the antenna coverage area (for example, when one side of the area is
30 ft, 60 ft or 120 ft as shown in the figure below), even a slight shift in the antenna location will result in an error. The
reason for this is that the antenna coverage area is equal to the area size, so it is not possible to cover the four corners
of the area with slight shifting.
In such a case, do not change the antenna location from the recommended antenna location, and instead change the
antenna settings ("How to change the settings of placed antennas" (page 33)). For example, change the antenna type
or transmission output.
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