Kongsberg Simrad SP60, Руководство пользователя

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Basic theory
Blocking
The movement of your vessel through the water will often
— especially in higher sea states — cause air bubbles to be
generated, and these bubbles will move along the hull. This is
called blocking. In order to prevent this noise from disturbing
your sonar operations, it is important to lower the sonar
transducer as far down below the hull as possible.
Check the noise yourself!
If you are bothered with acoustic or electric noise, you can easily
run a few simple tests to identify the cause of the problem.
Check acoustic noise
1 Click the
Setup
tab to open the menu.
2 Click the
Test
button to open the
System test
menu.
3 Click the
Test config
button, and select
Noise and VR
in the
parameter dialogue.
4 Click the
Close
button in the parameter dialogue to close it.
5 Observe the
Echo level
button on the
System test
menu, and
read the noise level.
The level your read in the button is the current noise in the
direction of the cursor. The noise is provided in dB, and the
number should be as negative as possible. For example, a reading
of –50 dB means that you have less noise than if you read –40 dB.
In order to reduce the noise, try to adjust the propeller pitch and
the number of revolutions.
Check electrical noise
1 Switch off all electric equipment that can cause electrical
noise.
2 Switch the equipment on again one at the time, and check
the sonar every time.
With luck, you will spot which of your electrical systems that
create the noise. To deal with the problem, consult your dealer
and/or a certified ships electrician.
Layers and deflections
Your sonar operations may also be disturbed by environmental
situations that you are unable to control. Two typical conditions
are temperature and salinity layers, and deflections caused by
increasing or decreasing water temperature.
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