Lowrance electronic LMS-525C DF GPS Receiver User Manual


 
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The Keel Offset feature eliminates the need for the navigator to men-
tally calculate how much water is under his keel.
Keel Offset lets you calibrate the digital depth, chart depth scale, chart
cursor depth and fish symbol depth displayed on the screen. To calibrate
the depth indicators, first measure the distance from the face of the
transducer to the lowest part of the boat. In this example, we will use 3.5
feet. This will entered as a negative 3.5 feet, which makes the depth indi-
cators perform as if the transducer's lower in the water than it really is.
1. Press
MENU|MENU| to Sonar Setup ENT. Use to select SET KEEL
OFFSET|ENT.
2. The Keel Offset dialog box appears. Press to change the plus (+)
sign to a minus (–) sign.
3. Press to the first number, then press to change the number to 3
4. Press to the second number, then press to change the number to
5, then press
EXIT. The depth indicators now accurately show the depth
of water beneath the keel.
NOTE:
If knowing the exact depth of water beneath the keel is less impor-
tant, you can calibrate the depth indicators so that they show the ac-
tual water depth from surface to bottom. To do this, first measure the
distance from the face of the transducer up to the surface (the water
line on the boat). In this example, we will use 1.5 feet. This will be en-
tered as a positive 1.5 feet, which makes the depth indicators perform
as if the transducer's higher in the water than it really is.
1. Press
MENU|MENU| to Sonar Setup ENT. Use to select SET KEEL
OFFSET|ENT.
2. The Keel Offset dialog box appears with a plus (+) sign at the
front of the box.
3. Press to the first number, then press to change the number
to 1.
4. Press to the second number, them press to change the num-
ber to 5, then press
EXIT. The depth indicators now accurately show
the water depth from surface to bottom.
Sensitivity & Auto Sensitivity
The sensitivity controls the ability of the unit to pick up echoes. Sensi-
tivity can be adjusted, because water conditions vary greatly. A low
sensitivity level (from zero to 50 percent) excludes much of the bottom
information, fish signals, and other target information.