Lowrance LMS-320 Operation Instructions Manual page 72

You may see fish symbols on the screen when actually, there are no
fish. The reverse is also true. The illustrations on the next page show
how Fish I.D. can actually miss fish that are present.
Does that mean Fish I.D. is broken? No — the feature is simply inter-
preting sonar returns in a specific way to help take some of the work
out of reading the screen. Remember: Fish I.D. is one of the many tools
we provide so you can analyze your sonar returns for maximum fish
finding information. This and other features can help you successfully
"see" beneath the boat under varied water and fishing conditions. So,
practice with the unit in both the Fish I.D. mode and without to become
more familiar with the feature. The default for Fish I.D. is off.
Sonar Features menu with Fish I.D. Symbols selected (at left, dual-
frequency menu; at right, single-frequency menu). When the check box
to the left is checked, the feature is on.
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