Furuno GP-7000F - Manual (Page 101)

10. VIDEO SOUNDER OPERATION
10-15
10.7 Erasing Weak Echoes
Sediments in the water or reflections from plankton may be painted on the
display in green or light-blue. These weak echoes may be erased as below.
Weak
echoes
Appearance of weak echoes
1. Push the [ENTER] knob to show the SENSITIVITY window.
GAIN 50* 000
NOISE LIMITER HIGH
CLUTTER 0
WHITE MARKER OFF
SIGNAL LEVEL OFF
*: For menu operation, both
of 50 and 200 frequencies appear.
Sensitivity menu
2. Rotate the [ENTER] knob to choose SIGNAL LEVEL and then push the
[ENTER] knob to show the signal level window.
OFF
SL1
SL2
SL3
SL4
OFF
SL1
SL2
SL3
SL4
SL5
SL6
SL7
SL8
SL9
PALETTE settings
on GENERAL menu: NOAA PALETTE settings
on GENERAL menu: other than NOAA
Signal level window
3. Rotate the [ENTER] knob to choose level of erasure or OFF as appropriate.
The higher the number the stronger the echo that will be erased.
4. Push the [ENTER] knob and [MENU] key in order to close the menu.
Note: Unlike “clutter,” signal level reduces display colors. Therefore, if you do
not wish to reduce colors, use clutter instead.