Simrad SN90, Руководство оператора

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38
381295/B
4 Select
Gain
.
5 Make the necessary adjustment.
The following methods can be used to adjust this setting:
a Select [
+
] or [
-
] to choose the requested setting.
b Place the cursor on the button. Press and hold the left mouse button. Move the
cursor horizontally over the button. Release the mouse button when requested
value is shown.
c Select the middle of the button to open it. If you have a keyboard connected to
the SN90, type the requested value.
6 Open the button and select
Apply to all
if you wish to use the chosen setting in all
the views in the current presentation mode.
Related topics
Starting normal operation, page 26
Changing the vertical angle of the sonar beams
In order to detect fish or schools in the water column you may need to change the angle of
the sonar beams. The sonar beams can be tilted electronically from -80 to 80° in 1° steps.
Context
The current tilt is shown with a solid line in the Vertical view. In the Horizontal view, the
current settings for range, gain and tilt are shown in the top left corner of the view.
At 0° tilt the sonar beam is transmitted parallel with the sea surface, while 80° tilt will
direct it towards the bottom.
The challenge is to find a tilt that prevents the fish echoes to be "buried" in reverberation
and bottom echoes.
• If you use a high tilt value (A) the fish are easily disguised by bottom echoes. A
strong RCG (Reverberation Controlled Gain) setting will remove the bottom echoes.
Simrad SN90 Operator Manual