Simrad ES80 Reference Manual page 433

Description
Occasionally, difficult environmental,
water or bottom conditions may
inhibit "bottom lock". The ES80
needs this "bottom lock" to locate the
correct depth, and to stay on it during
the operation, even if the depth
changes continuously. The
parameters are provided
Detection
to rectify this.
The
Bottom Detection
provide separate limits for minimum
and maximum depth. These limits
may be used to obtain "bottom
lock" on the depth when the ES80
is transmitting.
The
Bottom Backstep
echo the depth shall be detected.
Tip
If you have problems with bottom detection, you may consider disabling it. This can be
useful if you only wish to study targets in the water column.
If you use an Olex system, you can take advantage of the
detect seagrass. Decrease the bottom backstep value (make it more negative) so that
the bottom is detected at the top of an area of seagrass. The Olex will then detect the
real bottom, and the result is the height of the seagrass.
Details
Bottom Detection
This is an "on/off" switch. Select the box to enable the function.
Maximum Depth
The search for the bottom echo extends down to this depth whenever bottom
track is lost.
Use a slightly larger depth value than the deepest spot you expect to visit. This will
prevent annoyingly long ping intervals every time the bottom track is lost. A depth
value of either 0 (zero) or less than the minimum depth disables the bottom detector.
Note
If you set maximum depth to a value identical or smaller than the minimum value,
the bottom detection algorithm will be disabled. The ES80 will not detect the
bottom at all, and the displayed depth will be 0.00 m.
406273/C
Bottom
parameters
parameter allows you to manually modify where on the bottom
Functions and dialog boxes
parameter to
Bottom Backstep
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