Simrad ME70 - REV C, Руководство оператора

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Simrad ME70
Procedure
1 Click the
Active
icon.
This icon is located under the
Main
menu. It is
used to open the
Active
menu.
2 Click
Echogram
to open the
Echogram
dialog box.
The
Echogram
dialog box allows you to set up the parameters controlling the
echogram presentation. The three tabs control the horizontal lines, the echogram
type with applied TVG, and how sample data are converted to pixel data.
Tip
You can also open this dialog box from the short-cut menu in the Echogram view.
3
On the
Lines
tab, observe the various vertical markers that can be enabled.
Note
The annotations are controlled on the
Annotation
dialog box, but to place the
annotations in the echogram, you must enable them in the
Echogram
dialog box.
4 Enable the vertical markers you wish to see.
5 Click
OK
to save the current settings and close the dialog box.
Selecting TVG gain (Backscatter) in the Echogram dialog box
Purpose
The TVG can be chosen using the
Echogram
dialog box (described here), or with the
TVG
button on the
Active
menu.
Description
TVG means Time Varied Gain .
The whole idea with TVG is that echoes from fish shall have the same echo level (colour)
independent of their depths.
The ME70 has a TVG range down to 15 000 meters, which for all practical purposes is
unlimited. The ME70 does not have a TVG compensated receiver like most other echo
sounders. In the ME70 the TVG is made in software after the echoes from the receiver(s)
have been converted to digital format. In order to make this work the receiver must
have very large dynamic range.
The following TVG settings are available:
1
Pr (No TVG)
: Power.
2
Sv (20 log TVG)
: Volume backscattering strength.
3
Sp (40 log TVG)
: Point backscattering strength.
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