Cancel Navigation (Only When Navigating); Sensitivity; Upper Range (Advanced) - Humminbird 688ci HD DI Operation Manual

Cancel Navigation discards the current route and exits Navigation Mode. This
menu option will only appear when you are currently navigating a route. This
will not delete a previously-saved route.
Sensitivity controls how much detail is shown on the display and will adjust
the sensitivity of all sonar frequencies.
When operating in very clear water or greater depths, increase the sensitivity
to see weaker returns that may be of interest. If the sensitivity is adjusted too
high, the display may become too cluttered.
Decrease the sensitivity to eliminate the clutter from the display that is
sometimes present in murky or muddy water. If Sensitivity is adjusted too low,
the display may not show many sonar returns that could be fish.
NOTE: The Sensitivity setting is a global setting and will adjust the sensitivity
of all sonar frequencies.
Upper Range sets the shallowest depth range that will be displayed on the Sonar,
Split Sonar, Circular Flasher, and Big Digits Views. Upper Range is often used with
Lower Range.
NOTE: A minimum distance of 10 feet will be maintained between the Upper and
Lower Range regardless of the manual settings entered.
Flasher X-Press™ Menu
Cancel Navigation
(only when Navigating)
Settings: Press the RIGHT Cursor key and follow screen
instructions.

Sensitivity

Settings: Low = 1, High = 20; Default = 10
Upper Range
(Advanced)
Settings: Various, see below.
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