11.21 Interpreting The Display - Furuno GP-3700F Operator's Manual

11. ECHO SOUNDER

11.21 Interpreting the Display

This section provides, using typical examples, the information necessary for interpret-
ing the echo sounder display.
Minute mark
School of fish
Color bar
The color bar shows the relation between echo inten-
sity and echo color on the screen. The top color (red-
dish-brown) is the strongest color and the lower colors
the weakest. The bar can be used as a reference to es-
timate density of a school of fish, fish specifies and
hardness of the bottom. The background color can be
selected on the menu (see section 11.11).
Minute mark
The minute mark displays a minute worth of time with two colored bars, each bar 30
seconds in time. It is useful for estimating elapsed time.
Zero line
The zero line (transmission line) shows the position
of the transducer. The line disappears from the
screen when the range is shifted.
11-30
Color bar
Zero line
Bottom
Reddish brown
Strong Strong
Red
Yellow
Green
Weak
Blue
Color bar
Zero line
Range shifted