Simrad EK15 Reference Manual page 214

Simrad EK15
The biomass is automatically calculated based on choices you make in the
Calculation Interval
of pings, or a portion of the echogram view. The data is then taken from an
echo area starting immediately after the transmit pulse, and ending just over
the detected depth.
If you have limited your vertical range (using the
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.
b
Bottom
The echogram is related to the detected bottom. Stop depth (lower echogram
boundary) and vertical range are manually selected by the
buttons on the
Range
a successful bottom detection.
The biomass calculation is made in the same way as for
c
Pelagic
This echogram is nearly identical to the
biomass is calculated in a different manner.
The biomass calculations are not restricted by the bottom detection. This
means that the bottom echo will be included in calculations if it appears within
the chosen range.
3
Bottom TVG
Use this field to set up the TVG for the bottom detector.
4
User TVG
Use this spin box to define your own TVG curve.
Note
For this choice to take effect, the TVG type must be set to "User".
5
Apply to all
Click this box if you wish to implement your changes to all the echograms presently
in use on the EK15.
Topics
• Echogram; Lines tab on page 208
• Echogram; Echogram tab on page 210
• Echogram; Horizontal Axis tab on page 213
Related procedures
• Adding horizontal markers to the echogram on page 65
• Adding vertical markers and annotations to the echogram on page 66
• Selecting TVG gain in the Echogram dialog box on page 67
212
dialog box; within a given time frame, a defined number
menu. The echogram is only drawn for pings having
Main
Surface
and
Range Start Range
Start Depth
echograms.
Surface
echogram. However, the
and
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