Furuno WV-100 Operator's Manual page 17

The figure below is an example of echo during rainfall. This image is less reliable because no
stripes are visible, that is, the spectrum is broadened and there are no outstanding waves.
Wave spectrum
Difference for the wave result between this software and visual observation
The waves that can be detected by this software are gravity waves with a wave period of 4 sec-
onds or more. The waves with a short period, that is, the waves blown by the wind may not be
observed. Therefore, the visual wave direction and the analysis result may be different (see the
figure below).
Detection
sensitivity
4 sec.
2. PRINCIPLE OF OPERATION, HOW TO INTERPRET THE DISPLAY
Example image for low reliability
15 sec.
Wave period
11
Radar echo
: Wave radar (Detection sensitivity
for long period is high.)
: Visual observation (Detection
sensitivity for short period is high.)