Understanding Sonar History - Humminbird 757c Operation Manual

531528-1_A - 757c_787c2_&_787c2i_Man_Eng.qxp 10/16/2006 10:41 AM Page 22

Understanding Sonar History

It is important to understand the significance of
the display. The display does NOT show a literal 3-
dimensional representation of what is under the
water. Each vertical band of data received by the
control head and plotted on the display represents
something that was detected by a sonar return at
a particular time. As both the boat and the targets
(fish) may be moving, the returns are only showing
a particular segment of time when objects were
detected, not exactly where those objects are in
relation to other objects shown on the display.
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