Simrad SH90 - REV A, Руководство оператора

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Simrad SH90
What is RCG?
RCG
means Reverberation Controlled Gain . This is a
two-dimensional filtering of the received echoes in order to
suppress unwanted surface and bottom reverberation.
If you select Strong , the bottom echoes will disappear altogether
if the bottom is flat, while schools of fish close to the bottom
will be easier to see.
Note that scattered fish may be more difficult to spot if the RCG
function is active, as these can be misinterpreted as reverberation.
It is therefore important that you use the RCG with great care if
your are searching for scattered fish.
About tilt
The sonar beam can be tilted vertically in steps of 1 degree, and
the chosen tilt is shown on the sonar picture. At 0 degrees tilt
you will transmit the sonar beam in parallel with the sea surface,
while 60 degrees tilt will direct it almost straight down.
Figure 15 Tilt
(CD015005D)
C
B
A
The challenge will always be 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 will easily be disguised
by the bottom echoes, but a strong RCG setting will help. As
the distance from the bottom to the fish increases, the fish will
be easier to see when the RCG removes the bottom echoes.
However, this assumes that the fish echoes are considerably
stronger than the bottom echoes.
If you use a very small tilt (C) you will not be bothered by bottom
echoes. If the sea surface is gusty, you will however easily see
echoes from the waves. These echoes will normally be rather
weak, and will hardly move in relation to your vessel.
70
323773/C