Simrad SH90 - REV A, Руководство оператора

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Basic theory
Figure 14 Beam widths
A
Large
B
Normal
C
Narrow
The normal setting on the SH90 sonar is
Normal
. This setting is
basically designed for longer ranges.
You may also try setting
Auto
. This setting will automatically
adjust the beam width depending on the current range.
About Gain
You can adjust the gain in many different ways, but the most
important is the setting made by the
Gain
buttons on the
Operating Panel and on the
Horizontal
and
Vertical
menus.
If you have too much gain, you will see a sonar picture with too
many echoes. This is because the large amplification presents all
kind of noise and reverberation that the sonar picks up. If the
gain is smaller the noise and reverberation will disappear, but if it
the gain is too small the fish echoes may disappear as well. In
most cases you should try with a medium value.
On this sonar, you can adjust the horizontal and vertical gain
independent of each other. The horizontal gain is used when the
sonar operates in a horizontal mode, for example
Bow up or True
motion . If you switch to a mode with a vertical view, for example
True motion/Vertical , your sonar will need a different gain setting
for the beams directed towards the bottom.
To adjust the gain, see How to adjust the gain on page 25.
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