Upper Range (Advanced); Lower Range - Humminbird 398ci SI Combo Operation Manual

Upper Range sets the shallowest depth range that will be displayed on the
Down Imaging® Views. Upper Range is often used with Lower Range.
For example, if you are only interested in the area between 20 and 50 feet deep,
you should set the Upper Depth Range to 20 and the Lower Depth Range to 50.
The Sonar View will then show the 30 foot area between 20 and 50 and will not
show the surface or the bottom (assuming the bottom is deeper than 50 feet).
Greater detail will be shown for the area between 20 and 50 feet.
NOTE: A minimum distance of 10 feet will be maintained between the Upper and
Lower Range regardless of the manual settings entered.
Lower Range sets the deepest depth range that will be displayed by the unit.
Auto: The Lower Range will be adjusted by the unit to follow the bottom
automatically. Auto is the default setting.
Manual: You can adjust the Lower Range to lock the unit on a particular depth.
M will be displayed in the lower right corner of the screen to indicate the unit
is in Manual mode. Adjust the Upper and Lower Range together to view a
specific depth range, especially when looking for fish or bottom structure.
For example, if you are fishing in 60 feet of water but are only interested in the
first 30 feet (surface to a depth of 30 feet) you should set the Lower Depth
Range limit to 30. The display will show the 0 to 30 foot range, which allows
you to see a more detailed view than you would see if the display went all the
way to the bottom.
NOTE: A minimum distance of 10 feet will be maintained between the Upper and
Lower Range regardless of the settings entered manually.
Down Imaging® X-Press™ Menu
Upper Range
(Advanced)
Settings: 0 to 1490 feet, 0 to 497 meters (International
models only); Default = 0 ft

Lower Range

Settings: Auto to 1500 feet, Auto to 500 meters
(International Models only); Default = Auto
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