Understanding Sonar History - Humminbird 747c Operation Manual

531526-1_A - 747c_&_777c2_Man_Eng.qxp 10/2/2006 1:41 AM Page 16

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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