Furuno FSV85MK2, Manual

Page: 88 / 199

3. VERTICAL MODE
3-14
3.9.5 Reverberation
You may choose the length of reverberation for the echo signal, with [Reverberation]
in the [TX/RX Setting] menu on the [V] tab. The larger the value, the lower the rever-
beration effect, which makes it easier to see the echo signal. The setting range is 0-3.
3.9.6 Echo average
[Echo Average] on the [Picture Setting] menu in the [V] tab adjusts echo afterglow -
the amount of time an echo signal remains on the screen. This feature can be useful
for watching echo movement. The setting range is 0-7.
Setting between 1 and 3 :
Echoes are gradually displayed and afterglow remains on the screen longer as the
setting is increased.
Setting between 4 and 7 : Echoes are quickly displayed and af-
terglow remains on the screen longer as the setting is increased.
3.9.7 How to suppress sidelobes
False echoes produced by sidelobes may appear on the display depending on the dis-
tribution pattern of a school of fish and the positional relationship between it and a ma-
rine object (reef, etc.) and wake reverberation. To reduce these sidelobes, use
[Sidelobe Sup.] on the [TX/RX Setting] menu on the [V] tab.
Watch the echoes while adjusting the suppression. Under normal conditions, [Sidelo-
be A] is adjusted. The setting range is -3 to 3 (0 is OFF). The larger the setting, the
more the sidelobe is suppressed. For greatest suppression, use a negative setting (-
3 to -1).
Note: When a negative value is used, [TX/RX Mode] in the [Display Setting] menu is
automatically selected to [Alternative]. See "Display Setting Menu" on page 7-3 for
details.
For greater sidelobe suppression, use [Sidelobe Sup. B]. See "Sidelobe suppression
B" on page 2-19 for more information. Note that You cannot operate [Sidelobe Direc-
tion 1] and [Sidelobe Direction 2].