Pelagic Echogram; Trawl Echogram - Simrad ES70 - REFERENCE MANUAL REV A Reference Manual

Simrad ES70
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
dialog.
Echogram
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.
Related topics
• Start Range on page 114
• Range on page 113
• Echogram on page 158

Pelagic echogram

The pelagic echogram appears very similar to the surface echogram. However, the
biomass calculations are not limited by the bottom detection.
Example: In a pelagic echogram, set the
the echogram start from 20 meters below the sea surface (provided that the transducer
offset has been defined). Set
from 20 meters below the sea surface, and down to 60 meters below the transducer.
Provided that the depth is larger than 60 meters, the bottom contour is not shown.
Related topics
• Start Range on page 114
• Range on page 113
• Echogram on page 158

Trawl echogram

Trawl sensor systems communicate headrope depth and headrope-to-footrope distance
to the ES70 at regular intervals. The echogram covers the vertical opening of the
trawl including a small margin at each side. The headrope and footrope margins are
identical. Their size is selected in the
can be manually set in the
trawl opening, or when the measured headrope-to-footrope distance is unreliable. The
echogram is only drawn when trawl position information is available. The biomass
calculations are not limited by the bottom detection.
Related topics
• Start Range on page 114
• Range on page 113
• Echogram on page 158
46
Start Range
to 40 meters. The echogram will now show the area
Range
dialog. The headrope-to-footrope distance
Trawl
dialog for trawl sensor systems not measuring the
Trawl
Horizontal Axis
value to 20 meters. This will make
tab in the
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