Hondex HE-7300, Operation Manual

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2. HOW TO DISTINGUISH THE FISH SCHOOL
●
Important is comparison between display of fish school and catch
It is possible to distinguish the fish sort by display of fish school to some extent. But even if fish sort
is same, it's form making school is different according to difference of fishing ground and difference
of time (day and night, four seasons, variation of current).
The important thing to distinguish the fish sort is to know the sort according to their fishing ground
or fishing period and to find the useful point on the display by comparing between display of fish
school and actual catch.
3. HOW TO DISTINGUISH THE FISH VOLUME
●
Fish volume can be distinguished by density and size of fish school
As the harder density the transmitted wave is reflected strongly, you can distinguish the density of
fish school according to the strength of reflected echo (that is, different color). Normally we tend to
think the larger fish school on the screen the most fish volume. But when fish school are located
at the shallow depth and the deep depth, fish school at the deep depth is displayed bigger than at
the shallow depth. Because the transmitted wave spreads wider as it goes deeper and the reflected
wave spreads wider as it goes shallower. As this result, the deeper becomes the wider the width of
fish school becomes on the screen. The important thing to distinguish the fish volume is to judge
it according to size of fish school and the strength of reflected echo (color) while you keep "the
deeper fish school stays the bigger picture is displayed" in your mind.
Reflected
wave
Fish school B
Fish school A
Fish school A picture
(shallow)
Fish school B picture
(deep)
4. HOW TO DISTINGUISH THE NATURE OF BOTTOM
●
There are different natures of bottom such as rock, sand, mud or etc.
In case you distinguish the nature of bottom, you judge from the
thickness of bottom image and the situation of second reflection. At
the hard bottom like rock, reflection of transmitted wave becomes
strong and bottom image becomes thick and the second reflection
becomes easily to appear. On the other hand, at the soft bottom
like sand or mud the reflection becomes weak and bottom image
becomes thin and the second reflection becomes hard to appear.
<Rock>
<Sand or Mud>