Filter
Top Products
SENSITIVITY
Big
rocks or
stumps
on a smooth bottom send back
signals
above
the
The
sensitivity key
on the X-55A controls the
ability
of the unit to
pick up
echoes. A low
sensitivity
level excludes much of the bottom
information,
fish
signals,
and other
target
information.
High sensitivity
levels enables
you
to see this
detail,
but itcan also clutterthe
screen with
many
undesired
signals. Typically,
the best
sensitivity
level shows a
good
solid bottom
signal
with
Grayline
and some surface clutter.
When the X-55A
is in the Automatic
mode,
the
sensitivity
is
automatically
adjusted
to
keep
a solid bottom
signal
displayed, plus
a little more. This
gives
it the
capability
to show fish and other detail.
However,
situations occur where it
becomes
necessary
to increase or
decreasethe
sensitivity.
This
typically happenswhen you
wish to see more
detail,
so an increase in
sensitivity
is indicated. The
procedure
to
adjust
it
is the same whether the unit is
in
the
automatic or manual mode.
To
adjust
the
sensitivity, press
the SENS
key.
The
sensitivity adjust
menu
appears
at the bottom of the screen.
The
sensitivity
menu
has left and
right arrows, plus
a horizontal bar
graph.
The
graph gives
a visual indication of the
sensitivity
level. The number
above the INC arrow
also
shows
the
percentage
of
sensitivity
in use.
To increase
the
sensitivity
level, press
the
right
arrow
key.
As
you press
the
key,
the
menu's bar
graph
will
grow
wider and the
percentage
will
increase
in value. You can also see the difference on the chart record as
it scrolls. When the
sensitivity
is at the desired
level,
release the
key.
To decrease
the
sensitivity
level, press
the
key adjacent
to the left arrow.
The bar
graph
and
percentage
will decrease. When the
sensitivity
is at the
desired
level,
release the
key.
When
you
reach either the
maximum or
minimum
limit,
a
tone
sounds.
bottom
level
signal.
The
height
of the
signal depends
on
thetarget's
height.
Asyou
pass
overa
post,
it should be
clearlyvisible
as a short
lineextending
above the bottom
signal.
Asteep slope
returns a wide
signal,
the
steeperthewider. Signals
returned
from a
high
underwater cliff are
usually
the widest of all.
WATER TEMPERATURE AND THERMOCLINES
Water
temperature
has an
important-if
not
controlling-influence upon
the
activities of all fish. Fish are cold blooded and
their bodies are
always
the
temperature
of the
surrounding
water.
During
the
winter,
colder water
slows down their metabolism. At this
time,
they
need about a
fourth as
much food as
they
consume in the summer.
Most
fish don't
spawn
unlessthe
watertemperature
is within rathernarrow
limits. A surface
temperature
meter
helps identify
the
desired surface
water
spawning temperatures
for various
species.
Trout
can't survive in
streams
that
get
too warm. Bass and other
fish
eventually
die out when
stocked in lakes that remain too cold
during
the
summer. While some fish
have a
widertemperature
tolerance than
others,
each has a certain
range
within
which it tries to
stay. Schooling
fish
suspended
over
deep
water lie
at the level that
provides
this
temperature.
We assume
they
are the most
comfortable
here.
Thetemperature
of water in the lake is seldom constantfrom
topto
bottom.
(See
the
picture
on the next
page.) Layers
of
different
temperatures
form,
and the
junction
of a warm and cool
layer
of water is
called a thermocline.
The
depth
and thickness of the thermocline can
vary
with the season or
time
of
day.
In
deep
lakes there
may
be two
or more at different
depths.
Thermoclines are
important
to fishermen because
they
are areas where
fish are active.
Many
times bait fish will be above
the thermocline while
larger game
fish will
suspend
in or
just
below it.
The X-55A can detectthis invisible
layer
in the
water,
butthe
sensitivitywill
probably
have to be turned
up
to
see it.
When the Fish l.D. mode is
off,
the
depth
of the water will affect the size
and
shape
of the fish arch due to the
cone
angle
diameter. For
example,
if the cone
passes
over a fish in shallow
water,
the
signal displayed
on the
X-55A
may
not arch at all.
This is due to the narrow cone diameter and the
resolution limitations of the
display.
14
39
PDF compression, OCR, web-optimization with CVISION's PdfCompressor