381295/B
67
Related topics
Controlling the gain and range settings, page 63
Adjusting the intensity of the echo presentations
The effect of the
Gain
adjustment is minimized if you apply
RCG
(Reverberation
Controlled Gain) and
AGC
(Automatic Gain Control). The
Display Gain
is applied
towards the end of the filter sequence in the SN90. This means that you can use
Display Gain
if you are not completely satisfied with the results of the automatic gain
functionality.
Context
Display Gain
controls the "amount" of echo that is displayed, in other words the
"strength" or "intensity" of the echo presentation. The function thus increases or
decreases the presentation of the echo colours. Use this parameter together with
Gain
to
adjust the SN90 sensitivity.
For all practical purposes, adjusting
Display Gain
has the same effect as adjusting
Gain
.
Adjust the
Display Gain
so that you can see the targets without too much noise and
reverberation. The chosen setting is a matter of personal preferences.
Procedure
1
Open the
Display
menu.
2
Select
Display Gain
.
3
Adjust the setting to fit your requirements.
To change the setting, move the cursor to
either side of the button. Select the
left
side
of the button to
decrease
the value. Select the
right
side of the button to
increase
the
value. Select the middle of the button to open it.If you have a keyboard connected
to the SN90, type the requested value.
Related topics
Controlling the gain and range settings, page 63
Improving the recognition of fish and schools using receiver filters, page 79
Changing the tilt
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.
Summary of Contents for SN90
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