2
Unit Operation
SETUP MENU
—
CALIBRATION
Calibration
The Calibration Setup Menu allows the user to calibrate the
unit for Keel Offset, Water Type (salt or fresh) and Speed. These
calibrations help to ensure the Fishfinder 240 will provide the
most accurate readings at all times. To access the Calibration
Menu use the arrow keys to highlight the Calibration tab.
Keel O
Offset
The Keel Offset allows the user
to offset the surface reading for
the depth of a keel. Enter a posi-
tive number to offset a keel. It is
also possible to enter a negative to
compensate for a large vessel that
may draw several feet of water.
The Keel Offset will be reflected
only in the Depth reading .
Water T
Type
Since sound waves travel
through fresh and salt water at
different rates it is necessary to
select the Water Type to ensure
accurate readings on the unit.
To change the Water Type,
highlight the Water Type field
and press
E
. Use the
U
or
D
arrow to select the Water Type
then press
E
to accept the
selection.
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