Down Sensitivity; Upper Range (Advanced) - Humminbird 700 Series Operating Manual

Down Sensitivity controls how the sonar returns are displayed on the
Down Imaging™ Views.
Increase the Down Sensitivity to reveal weaker returns that may be of interest,
especially in very clear water or greater depths. A high Down Imaging™
Sensitivity setting shows more sonar returns from small baitfish and suspended
debris in the water; however if the Down Imaging™ Sensitivity is adjusted too
high, the display may become too cluttered.
Decrease the Down Sensitivity to eliminate the clutter from the display that is
sometimes present in murky or muddy water. If Down Imaging™ Sensitivity is
adjusted too low, the display may not show many sonar returns that could be
fish.
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.
Down Imaging™ X-Press™ Menu

Down Sensitivity

Settings: Auto, 1 to 20, where Low = 1, High = 20;
Default = 10
Upper Range
(Advanced)
Settings: 0 to 1490 ft or 0 to 497 m [International Models
only]; Default = 0
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