3. VERTICAL MODE
3-10
3.9
How to Reject Sonar Interference and Noise
While observing the sonar picture, you may encounter occasional or intermittent noise
and interference. These are mostly caused by on-board electronic equipment, engine
or propeller noise, or electrical noise from other sonars being operated nearby.
3.9.1
How to identify the noise source
To eliminate noise effectively, you should first identify the noise source as follows:
1. On the [Test] menu, turn off [TX] to stop transmitting. Turn on all on-board elec-
tronic equipment one by one while observing the picture. If noise appears on the
sonar display, that equipment is emitting noise. Check the offending equipment's
ground and installation.
2. Run the boat at various speeds to check if the noise is speed dependent.
If neither of the above two steps has effect on the picture, adjust one of the following:
3.9.2
Interference rejector
The interference rejector suppresses randomly appearing noise, sea surface reflec-
tions, and interference from other acoustic sounding equipment. Set it so that noise is
just eliminated. Do not use an unnecessarily high setting since it may also reject small,
wanted echoes.
1. Press the
MENU/ESC
key to show the main menu.
2. Click [Picture Setting].
3. Press the
H/V/S
key to select the [V]
tab.
4. Click [Int Reject] or [Int Reject (ES)].
• [Int Reject]: Use this item to sup-
press sea surface reflections, and
sea surface reflections.
• [Int Reject (ES)]: Use this item to
suppress interference from other
acoustic sounding equipment.
5. Click
S
or
T
to change the setting.
• [Int Reject]: The setting range is 0 to 3. The degree of rejection in ascending
strength is 2, 1, 3. “0” disables the interference rejector.
• [Int Reject (ES)]: Use this item to suppress interference from other acoustic
sounding equipment. The degree of rejection in ascending strength is 1, 2, 3.
“0” disables the interference rejector.
6. Click [Quit] on the setting box to close the box.
7. Long-push the
MENU/ESC
key to close all menus.
3.9.3
Shift TX frequency
If the interference can not be suppressed by the interference rejector or change in TX
interval, shift the Tx frequency with the [Freq Shift] menu.
1. Press the
MENU/ESC
key to show the main menu.
Picture Setting
Quit
H2 P1
Echo Average
: 3
Int Reject
: 2
Int Reject (ES)
: 2
Smooth Echo RNG
: 2
Smooth Echo CIR
: 0
2nd Echo Rej.
: 0
V P1
H1 P1
Summary of Contents for FSV-2S
Page 1: ...COLOR SCANNING SONAR FSV 25 FSV 25S OPERATOR S MANUAL www furuno com Model ...
Page 14: ...SYSTEM CONFIGURATION xii This page is intentionally left blank ...
Page 74: ...2 HORIZONTAL MODE 2 44 This page is intentionally left blank ...
Page 92: ...4 NUMERIC GRAPHIC DATA DISPLAY 4 4 This page is intentionally left blank ...