Humminbird 998c SI - Manual (Page 101)

91 Sonar X-Press™ Menu
Bottom Lock
(Sonar Zoom View only)
Settings: Off, On; Default = Off
Bottom Lock changes the mode of the zoomed view in the Sonar Zoom
View. Bottom Lock continuously graphs the bottom at a constant point on
the display regardless of changes in depth. This “flattens“ out the bottom
contour but is effective at showing fish on or near the bottom.
Bottom Range
(Sonar Zoom View only, when Bottom Lock is On)
Settings: 10 - 60 feet, 2-10 fathoms, or 3-20 meters
[International Models only], Default = 15 feet
Bottom Range allows you to control how much of the water column,
measured up from the bottom, is shown in the Sonar Zoom View. Choose a
small value to see low-lying bottom structure or details of the bottom return.
Choose a larger value to see large structure in deeper water.
NOTE: It is possible to set the Bottom Range to be greater than the depth. In this
case, you may see surface clutter in a wavy band that mirrors changes in the
depth.
Cancel Navigation
(only when Navigating)
Settings: Press the RIGHT Cursor key and follow
screen instructions.
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.