Bottom Lock (Sonar Zoom View Only) - Humminbird 398ci SI Combo Operation Manual

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.
Sonar X-Press™ Menu
Bottom Lock
(Sonar Zoom View only)
Settings: Off, On; Default = Off
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