How To Reject Sonar Interference And Noise; How To Identify The Noise Source - Furuno FSV-35 Operator's Manual

3. Press the H/V/S key to select the [V] tab.
4. Select [TX Pulse Length] 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 0-9. The higher the setting, the longer the pulse length.
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.
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. Stop transmission on the [Test] menu; turn on [TX]. Turn on the power of all on-
board 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. VERTICAL MODE
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