History Screen Operation; Auto Range - Navman Fish 4430 Installation And Operation Manual

3-2 HISTORY screen operation

Select MAIN MENU - HISTORY to display the
HISTORY screen.
The HISTORY screen displays the most recent
echoes on the right of the screen and the
oldest echoes on the left. These eventually
disappear off the screen.
The vertical bar on the right edge of the screen
is the zoom bar. This shows the zoom range. To
adjust the zoom range (see section 3-4).
Fish symbol
with depth
Bottom
The HISTORY screen does not show a fixed
distance travelled by the boat; rather, it
displays what has passed below the boat
during a certain period of time. The actual
display depends upon the boat speed and the
depth of the water.
As the boat travels through shallow water, the
echoes have less distance to travel between
the objects and the boat. This means that
the HISTORY screen display moves across the
screen more quickly than when the boat is
travelling in deep water. In deep water, the
echoes take longer to travel between the
objects and the boat, producing a display that
moves across the screen more slowly.
Note 1: Different fish symbols can be selected (see
section 4-3).
Note 2: The depth of bottom can be adjusted for keel
offset (see section 4-7).
10
Zoom bar
Alarms
Range
Range is the depth of water displayed vertically.
The NAVMAN fishfinder has two range modes,
Auto Range and Manual Range:
· In Auto Range, the fishfinder adjusts the
depth range automatically so that the
bottom is always shown in the lower part
of the screen. The use of Auto Range is
recommended.
· In Manual Range, the fishfinder shows only
a selected depth range. In areas of rapidly
changing bottom depth, such as the sea
floor around pinnacles, it can be useful to
prevent the screen from rescaling to always
show the bottom. If the bottom is deeper
than the specified depth range, it will not
be shown on the display screen.
To change the range mode, (see section 3-8).
Changing the Gain Mode
Gain (sensitivity) controls the amount of detail
displayed on the screen. The fishfinder has two
gain modes, Auto Gain and Manual Gain:
· In Auto Gain, the gain is automatically adjusted
to compensate for water depth and clarity. The
use of Auto Gain is strongly recommended
when learning to use a fishfinder, or when
travelling at speed.
· In Manual Gain, the user can adjust the gain
to compensate for water depth and clarity.
Manual settings range from 1 to 9. High
settings may amplify normal background
noise until it appears as random pixels on
the screen. The ideal setting produces only
a small number of random pixels. Normally
the best results with a fishfinder are
obtained in Manual Gain but practice and
experience are required to understand how
to adjust the gain correctly.
To change between Auto Gain and Manual
+ -
Gain, hold or . The Gain mode will be
displayed briefly at the bottom of the screen.
When in Manual Gain the gain symbol
shown at the top of the display, followed by the
+
gain level. Press to increase the gain level or
-
press to decrease the gain level.
Fish 4430/4431 Installation and Operation Manual
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