Eagle Electronics 640c Fish Finder User Manual


 
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Adjusting sensitivity in Auto Sensitivity Mode is similar to manually ad-
justing a car's speed with the accelerator pedal while cruise control is on.
You can tell the car to run faster, but when you let off the gas the cruise
control automatically keeps you from running slower than the minimum
speed setting. In the unit, auto mode will let you increase sensitivity to 100
percent, but the unit will limit your minimum setting. This prevents you
from turning sensitivity down too low to allow automatic bottom tracking.
When you change the setting with auto turned on, the unit will continue to
track the bottom and make minor adjustments to the sensitivity level, with
a bias toward the setting you selected.
Adjusting sensitivity in Manual Sensitivity Mode is similar to driving a
car without cruise control — you have complete manual control of the
car's speed. In the unit, manual mode allows you to set sensitivity at
100 percent (maximum) or zero percent (minimum.) Depending on wa-
ter conditions, the bottom signal may completely disappear from the
screen when you reduce sensitivity to about 50 percent or less.
Try adjusting sensitivity in both auto and manual modes to see how
they work.
To adjust sensitivity:
1. Press
MENU|ENT.
2. The Sensitivity Control Bar appears. Press to decrease sensitivity.
Press to increase sensitivity. When it is set at the desired level, press
EXIT. When you reach the maximum or minimum limit, a tone sounds.
Sonar Menu with Sensitivity command selected (left).
The Sensitivity Control Bar (right).
NOTE:
If you want to change the sensitivity in Manual Mode, first turn off
Auto Sensitivity. From the Sonar Page, press
MENU| to AUTO