3. VERTICAL MODE
3-9
3.8
How to Adjust Strong, Weak Echoes
3.8.1
AGC
The AGC functions to automatically reduce the receiver gain only against strong
echoes such as the bottom or a large school of fish. Since weak echoes remain unaf-
fected, a small school of fish becomes easier to detect. Adjust it so that the AGC works
only on bottom reflections. Do not set it too high; weak echoes may be missed.
1. Press the
MENU/ESC
key to show the main menu.
2. Select [Gain Setting] then push the left-click button.
3. Press the
H/V/S
key to select the [V] tab.
4. Select [AGC] 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 higher the degree of sup-
pression.
6. Select [Quit] on the setting box then push the left-click to close the box.
7. Long-press the
MENU/ESC
key to close all menus.
3.8.2
Near AGC
When the water is shallow or heavily sedimented, the reflected echoes from close-in,
unwanted echoes may be excessively strong. In this case, a school of fish which is
displayed at between 300 and 500 m may disappear gradually when the ship starts
approaching the school of fish.
Use the Near AGC feature to suppress this strong echo. Normally set it between 3 and
4, however, this setting depends on the sea area. Do not set it too high; all echoes
(including noise) from near distance may be painted in red.
1. Press the
MENU/ESC
key to show the main menu.
2. Select [Gain Setting] then push the left-click button.
3. Press the
H/V/S
key to select the [V] tab.
4. Select [Near AGC] then push the left-click
button to show the setting dialog box.
5. Select [Near AGC] again then push the left-
click button.
6. Select
S
or
T
then left-click to change the
setting.
The setting range is -30 to 30. The higher the setting, the stronger the echo level
on near range.
7. Select [Quit] on the setting box then push the left-click button to close the box.
8. Long-press the
MENU/ESC
key to close all menus.
Note:
Set the effective range of [Near AGC] with [Near AGC Distance]. The setting
range is 20 to 500 (or 3000) m, in 20 m increments. The setting range can be changed
in the system menu. For details, contact your dealer.
Summary of Contents for FSV-35S
Page 1: ...COLOR SCANNING SONAR FSV 35S OPERATOR S MANUAL www furuno com Model ...
Page 12: ...SYSTEM CONFIGURATION x This page is intentionally left blank ...
Page 88: ...4 NUMERIC GRAPHIC DATA DISPLAY 4 4 This page is intentionally left blank ...
Page 118: ...7 RECORD RECALL OPERATION 7 8 This page is intentionally left blank ...
Page 138: ...APPENDIX 1 MENU TREE AP 6 This page is intentionally left blank ...