Basic Sonar Operation
This section addresses the unit's most basic sonar operations. The in- structions presented in Sec. 3 follow a chronological order. Sec. 4, Sonar Options & Other Features, will discuss the more advanced functions and utilities. Material in Sec. 4 is arranged in alphabetical order.
Before you turn the sonar unit on, it's a good idea to learn about the dif- ferent keys, the Main Menu, the four Page screens and how they all work together. BUT, if you just can't wait to get on the water, turn to the
Keyboard
4
8
9
27
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The SeaFinder 640c DF sonar unit showing full sonar chart screen display and keyboard.
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