Simrad ES70 - DOWNLOAD AND INSTALLATION REV B, Руководство оператора

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Simrad ES70
vertical range (using the
Range
and
Start Range
settings), the resulting area is used for
the biomass calculation. If the seabed is clearly defined with a unique bottom detection,
the bottom echo will not be included in the calculations. Therefore, if you switch the
bottom detector off, the bottom echo will be included in the calculation.
Bottom echogram
This echogram is related to the detected bottom. Stop depth (lower echogram boundary)
and vertical range are manually selected by the
Start Depth
and
Range
buttons on the
Main
menu. The echogram is only drawn for pings having a successful bottom detection.
Figure 15 Bottom echogram
A
This is the start depth of the
echogram.
In a bottom echogram it is normally
it is set up with
Start Range
set
to a relative small negative value.
The value defines how many meter
above the bottom the echogram will
start.
B
This is the bottom.
Since the echogram is related to
this bottom, it appears to be flat.
Fishes close to the bottom is then
easy to see.
The range from the start depth above the bottom and down to some distance below
the actual bottom is defined with the
Range
button on the
Main
menu.
Example 6 Start Range and Range in bottom related echogram
In a bottom echogram, set the
Start Range
value to –5 meters. This will
make the echogram start from 5 meters above the bottom. Set
Range
to
the 5 meters plus 10 = 15 meters. The echogram will now show the area
from 5 meters above the depth, and down to 10 meters “below” the
bottom. The bottom contour will appear as a flat line.
C This text identifies the transducer used to create the echogram.
D This is the scope view.
This view presents individual colour lines. The colour and length of each line
reflects the received echo amplitude.
E
By default, the “ping time” and the depth range is shown in the bottom left side of
the echogram. In the bottom right corner, the “ping time” is the same as current.
This information can be changed using the options on the
Horizontal Axis
tab in the
Echogram
dialog.
F This is the lower end of the depth range. It is normally a few meters below the
bottom contour, depending on the chosen range.
The biomass calculation is made in the same way as for
Surface
echograms.
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