Furuno FSV-35S, Operator'S Manual

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2. HORIZONTAL MODE
2-15
2.8 How to Suppress Bottom and Sea Surface Re-
flections in Shallow Waters
In shallow fishing grounds with hard or rocky bottom, bottom reflections often interfere
with wanted fish echoes and they can not be eliminated sufficiently with the aforemen-
tioned TVG and AGC functions, especially when the Tilt is set to a larger angle in order
to track schools of fish approaching within 400 m. In such cases try to reduce the out-
put power by adjusting the Tx power instead of turning down the gain. The picture be-
comes clearer when the output power is reduced rather than when the gain is
decreased as illustrated below.
1. Press the MENU/ESC key to show the main menu.
2. Select [TX/RX Setting] then push the left-click button.
3. Press the
H/V/S key to select [H1] or [H2] tab.
4. Select [TX Power] then push the left-click button.
5. Select
S or T then push the left-click button to change the setting. The setting
range is 0 to 9. The higher the setting the greater the TX power.
6. Select [Quit] on the setting box then push the left-click button to close the box.
7. Long-press the
MENU/ESC key to close all menus.
Fish echo
Fish echo
weakened
Fish echo
INCORRECT
METHOD
CORRECT
METHOD
Reduce TX POWER
with GAIN kept
constant
TVG and AGC
adjusted with
TX POWER kept high