Furuno FSV-84 manual Changing Tx interval, Shifting Tx frequency, How TX Interval works

2. HORIZONTAL MODE

2.9.3Changing Tx interval

When other sonars nearby are operating the same transmission interval as that of own ship’s sonar, an interference ring appears on the display. To erase the interference ring from the screen, reduce the TX INTERVAL on the H-SCAN SETTING menu.

Interference

Tx interval high Tx interval lowered

How TX INTERVAL works

1.Press the [MENU] key to open the menu.

2.Select the H-SCAN SETTING menu and press the [MENU] key.

3.Select TX INTERVAL and press the [MENU] key.

4.Adjust setting from the dialog box as appropriate and press the [MENU] key. The setting range is 0-9. The higher the setting the longer the Tx interval. The setting 0 is same as the setting 9.

5.Select QUIT and press the [MENU] key.

6.Select QUIT at the top of the menu screen and press the [MENU] key to close all menus.

Note: When the sonar is used in shallow water with the range set between 60 m and 200 m and Tx cycle at “9”, bottom reflections caused by the 2nd-to-the-last transmission may appear on near ranges. Lower the Tx interval by 2 or 3 steps to suppress them.

2.9.4Shifting Tx frequency

If interference cannot be suppressed by the interference rejector or Tx interval, shift the Tx frequency with FREQ SHIFT on the H-SCAN SETTING menu.

1.Press the [MENU] key to open the menu.

2.Select the H-SCAN SETTING menu and press the [MENU] key.

3.Select FREQ SHIFT and press the [MENU] key.

4.Adjust setting from the dialog box as appropriate and press the [MENU] key. The setting range is -65 to +65.

5.Select QUIT and press the [MENU] key.

6.Select QUIT at the top of the menu screen and press the [MENU] key to close all menus.

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