Display And Operating Modes; Echo Mode; Autofish Mode - Navman F400 Installation And Operation Manual

The FISH400 has five modes of operation.
These are Echo, Echo + Analogue Scope,
AutoFish, AutoFish + Analogue Scope and
Navigate.

Echo mode

The Echo mode displays the return signals as
they are received from the transducer. Fish
appear as arches and not as fish symbols. The
length of the arch will indicate the relative size of
the return echo and size of the fish.
The Echo mode enables the unit to display
echoes caused by surface turbulence, thermal
layers, plankton or transducer noise when the
boat is moving. This mode is very useful for the
experienced user.
The digital display in this sample window is
indicating the depth of the bottom. The display
units are also user selectable
NAVMAN Fishfinder User Manual

Autofish mode

The Autofish mode automatically analyses the
return echoes and displays echoes with fish
icons (the bigger the echoes, the bigger the
icon!).
The return echo is caused when the sonar beam
strikes the air stored in the fishes swim bladder.
Certain types of fish have larger swim bladders
than normal so the size of the icon is not always
a reliable way to indicate the relative size of the
fish.
In the Autofish mode, unnecessary surface
noise is reduced from the top of the screen. This
mode is recommended when your boat is moving
along at higher speeds.
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