GPSMAP 3005C Owner’s Manual
79
U
SING
S
ONAR
>
S
ONAR
T
AB
•
Automatic Scroll Speed Limit
—automatically adjusts the Scroll rate with
the speed of your vessel. Entering your maximum cruising speed produces
a 100% scroll rate when you reach that speed. One half of that speed
produces a 50% scroll rate, and so on. The default is
30.0 kt
.
• Keel Offset
—allows you to offset the surface reading for the depth of a
keel. This makes it possible to measure depth from the bottom of your keel
instead of from a transducer’s location near the water line. Enter a positive
number to offset for a keel. You can also enter a negative number to
compensate for a large vessel that may draw several feet of water, requiring
the transducer to be submerged if you want to measure from the water line.
The
Keel Offset
is reflected in the depth reading.
Transducer at surface.
Enter (+) a positive
number to show depth
from bottom of keel.
Transducer at bottom of keel.
Enter (-) a negative number to
show depth from surface.
•
Transducer Type
—allows you to specify what type of transducer you are
using, either
Dual Beam
or
Dual Frequency
.
•
Custom Range
—allows you to specify a custom viewing range or scale.
When
On
, this range appears as
Custom
in the Range setting. The left
value is the top of the scale and the right value is the bottom of the scale.
•
Calibrate Water Speed
—this is available only if you are using a speed-
capable transducer/sensor. Calibration is required to ensure that the Water
Speed shown on your unit is accurate. The unit automatically uses the GPS
ground speed, if it is available, for comparison on the calibration. If a GPS
ground speed is not available, use either your boat’s speedometer reading
(not always accurate) or a stopwatch to determine your speed over a certain
distance (distance / time = speed). It is recommended that the calibration
take place in water having little or no current.
To calibrate the water speed:
1. On the
Sonar
tab, press the
Cal Water Spd
soft key.
2. Bring the boat to a cruising speed. Both the top ground and uncalibrated
water speeds are shown at the bottom of the calibration window. Note your
top speed, stop the boat, and press
ENTER
.
3. By default, the top ground speed automatically appears in the
“What
was your top water speed?”
field. If a ground speed is not available,
the top uncalibrated water speed is used instead. If the new speed is
correct, highlight
OK
, and press
ENTER
. If you want to manually enter
a calibration, press
ENTER
on the speed field, enter a new speed, and
press
ENTER
.
Graph Sub Tab
Use the Graph sub tab to select the color scheme, fish symbols, and scale.
Summary of Contents for GPSMAP 3005C
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