Furuno GP-7000F Operator's Manual page 109

ECHO OFFSET (50 kHz, 200 kHz)
If the on-screen echo level appears to be too weak or in manual operation too
strong and the level cannot be adjusted satisfactorily with the gain control on the
display unit, adjust echo offset to compensate for too weak or too strong echoes.
BOTTOM LEVEL (50 kHz, 200 kHz)
If the depth indication is unstable in automatic operation or the bottom echo
cannot be displayed in reddish-brown by adjusting the gain control in manual
operation, you may adjust the bottom echo level detection circuit, for both 50
kHz and 200 kHz, to stabilize the indication.
Note: If the BOTTOM LEVEL is set too low, fish echoes may be recognized as
the sea bottom, and the depth indication may be unstable. Reversely, if
the setting is too high, the depth indication will not be displayed.
SMOOTHING
Smoothes echoes to present stable display. The higher the setting the greater
the smoothing.
DEPTH INFORMATION
Selects the size of the depth indication, Large, Small or Off.
ECHO SOUNDER SIMULATION
Starts the echo sounder simulation mode.
For the SENSOR SETUP menu, see the installation manual.
10. VIDEO SOUNDER OPERATION
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