X515C DF & X510C Manual - Lowrance

Typically, the best sensitivity level shows a good solid bottom signal with
some surface clutter.
Automatic Sensitivity
The default sensitivity mode is automatic. The unit bases the sensitivity
level on water depth and conditions. When the unit is in the automatic
mode, sensitivity is automatically adjusted to keep a solid bottom
signal displayed, plus a little more power. This gives it the capability to
show fish and other detail.
However, situations occur when it becomes necessary to increase or
decrease the sensitivity. This typically happens when you wish to see
more detail or when wave action and boat wakes create enough tiny air
bubbles to clutter much of the water column. In that case, a decrease in
sensitivity is indicated to reduce some of the clutter.
The control bar used to adjust sensitivity is the same whether the unit
is in the automatic or manual mode. In automatic you can adjust sensitivity
up to 100 percent but the unit will limit your minimum setting.
In auto, the unit will continue to make small adjustments, allowing for
the setting you selected.
In manual mode, you have complete control over sensitivity, with the
ability to set it anywhere from zero to 100 percent. Once you select a
level in manual, the unit will continue to use that exact sensitivity setting
until you change it or revert to auto mode.
To adjust sensitivity in auto mode:
1. Press MENU|ENT.
2. The Sensitivity Control Bar appears. Press ↓ to decrease sensitivity;
press ↑ to increase sensitivity. When it's set at the desired level, press
EXIT. (When you reach the maximum or minimum limit, a tone sounds.)
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