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data received in this window without any processing (so called “raw” data). It is more complicated
for perception than the fish signs, however it provides more additional data for an experienced
user.
In RTS window one can take notice of the echo-signals located in the beam zone. For
example, vertically falling load (feedbox) will be clearly seen in RTS, but it will not be detected
as the fish and we will not see the fish contour on the screen.
In FISH ID
mode the bottom will be displayed in the form of the long dark strip, and in
respect of its thickness one can judge the bottom nature.
The light strip in one pixel will be present in the neat bottom line. It is this very strip that
shows the place from where the measurement and calculation of the depth value is performed.
Everything that is located above this strip will be referred to the near bottom structures. Soil density
provides additional data displayed under the depth figures. For instance, figures 1-5 is typical of
the muddy bottom, and 15-20 – for the hard bottom. To be precise, this value does not characterize
the bottom density as such but the strength of the signal reflected from it: the bigger they are, the
better the bottom reflects the signal and the smaller the depth is (because with the distance increase
the signal weakens).
For correct definition of the fish the properly set sensibility level has a significant
importance. With exaggerated sensibility level (especially in summer on a moving boat) when the
sonar can register even the weedy water, thermo-cline or suspended particles, it is quite possible
that these irregularities can appear on the screen in the form of the fish symbols. Stakes of tiny fish
can also cause appearance of big fish contours in the screen. Reducing of sensitivity will enable
to filter out these “disturbing” factor. It is impossible to provide specific recommendations
regarding setting the sensitivity level as condition at the reservoirs differ considerably.
In Praktik sonar, in FISH ID mode, fish of three sizes can be displayed. In the process of
the unit development and identification algorithms adjustment we used the fish of the following
sizes: carp 150g - for small fish contour, 500-700g- for average contour and carp for 1kg for big
Summary of Contents for Praktik 6 Pro 2
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