Raymarine L1250DRC, Owner'S Handbook Manual

Page: 136 / 246

6-6 HD Series Fishfinders
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As you move the slider, the value displayed in the slider is updated. The
new setting takes immediate effect.
Note: Because the changes to the settings take effect immediately, you can-
not revert to the previous settings by pressing
CLEAR
.
5. When you have set all the controls to the levels you desire, press ENTER or
CLEAR
to return to the default display.
Gain
The
GAIN
, or sensitivity, of the display adjusts background noise by varying
echo strength for display. The value of the GAIN control determines the
strength above which echoes are displayed. If the gain is low only the strongest
echoes are displayed. As the gain is increased weaker echoes (from air
bubbles, for example) are displayed.
Pressing the
GAIN
soft key cycles the sounder from manual through three
levels of automatic gain adjustment.
Manual gain should be set high enough to see fish and bottom detail but
without too much background noise. Generally, a high gain is used in deep
and/or clear water; a low gain in shallow and/or murky water.
The automatic gain modes finds the ideal sensitivity level for you, based on
depth and water conditions. Automatic gain modes take advantage the
hardware’s advanced DSP technology. As a result, the sounder typically
achieves a sharper image in any of the automatic gain modes than is possible
in manual mode.
The fishfinder provides three pre-defined automatic gain settings:
CRUISING
is the lowest automatic gain setting. It is ideal for viewing sonar
images with a minimum of background noise as you are travelling to your
fishing spot.
TROLLING
is a slightly higher gain setting that displays more detailed echoes as
you search for targets.
FISHING
is the highest automatic gain setting. It gives the best details of the
targets you have located but also displays the most background noise and
surface clutter.
Note: The automatic gain modes are named so as to suggest when you might
use them. However, it is not necessary for you to select Fishing Mode, for ex-
ample, only when you are fishing. You may want to take advantage of Fishing
Mode’s higher gain even when cruising at high speeds. Use your personal
preference to determine which automatic gain mode to use.
MULTI GAIN
MANUAL
GAIN
80%
CRUISING
AUTO
45%
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