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User Manual
6.5
Can I always leave the Fish Finder in Full Auto/(auto
gain and auto range) mode?
Yes, but note that the full auto mode suits the 90% of the cases, however in
extreme situations the auto modes mail fail and thus it is necessary to switch
to the Manual mode.
6.6
What are extreme situations in which auto modes may
fail?
When the bottom is very deep, at high boat speed, when the bottom is very
shallow (< 5 feet), when the water is full of materials in suspension, with bad
sea conditions.
6.7
What should I do if the auto modes fail?
Failure of auto modes can happen for various reasons. Hereafter you can find
a range of possibilities.
6.8
Auto-range fails in very shallow waters displaying a
digital depth readout deeper than the actual value.
What should I do?
This usually happens if the STC is set to LONG or MID and the bottom is
shallow or SHORT if the bottom is very shallow causing the auto-range to
hook to the second or third echo from the bottom (since in shallow waters the
sound bounces more times back and forth the surface to the bottom). Try
decreasing the STC value to SHORT in shallow waters or to switch it to VERY
SHORT or OFF.
6.9
Auto range fails, and the digital depth readout displays
a very shallow reading. What should I do?
This usually happens if the STC is off or is set to a low value causing disturbs
from surface clutter to be stronger than bottom echoes. Try increasing the
STC value. As general rule STC has to be set as in shallow waters and LONG
in depth waters.
6.10 Auto-range fails in very deep waters displaying a digital
very shallow depth readout. What should I do?
The Fish Finder capability to detect the bottom decreases as the bottom depth
increase. If the bottom composition is soft as mud, if the sea conditions are
bad, if there are thermoclines or the water is full of materials in suspension it
can further decrease thus causing the digital depth readout to fail. When this
happens the auto-range algorithm also fails. To recover from this situation it
is necessary to switch to manual range mode and to set the manual depth
mode. When manual depth mode is selected the algorithm that calculates the
digital depth readout searches for the bottom within the range manually se-
lected by the user. At this point it is necessary to increase manually the range
until the bottom becomes graphically visible. If the echoes from the bottom
are strong enough, the Fish Finder shall look to the bottom giving a correct
depth reading and shall be possible to return in auto range mode. Please note
that if one or more of the conditions that reduce the echoes from the bottom
listed above is true the bottom may be not visible at all, in this situation a
