Furuno FR-10, Operator'S Manual

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2. OPERATION
2-13
8. Press the MENU key to close the menu.
Note: Rotate the A/C SEA knob while the [Gain Mode] is [Auto], the window
shown below appears. Select [Yes] with the cursorpad and the Enter key to switch
the mode to [Manual]. Select [No] or press the CANCEL/HL OFF key, the screen
will disappear with the mode [Auto].
Manual adjustment of sea clutter
1. Rotate the A/C SEA knob to adjust the sea clutter.
Note: When the sea clutter is properly adjusted, the clutter is broken into small
dots, and small targets become identified. If the setting is too low, targets are hid-
den in the clutter. If the setting is higher than necessary, both sea clutter and tar-
gets disappear from the display. Normally adjust the knob until the clutter has
disappeared to leeward, but a small amount of the clutter is visible windward.
2. Press the MENU key to close the window.
2.12 How to Reduce the Rain Clutter
The reflections from the rain or snow appear on the screen. These reflections have the
name "rain clutter". When the rain clutter is strong, targets in the rain clutter are hidden
in the clutter. Reflections from the rain clutter are easily identified from true targets by
their wool-like appearance.
The rain clutter function works like the sea clutter function, adjusting the receiver sen-
sitivity, but in longer range. The higher the setting the more clutter is removed. The
rain control breaks the continuous display of rain or snow reflections into a random
pattern. When the rain clutter hides the targets, adjust the rain clutter (automatic or
manual) to reduce the clutter.
How to select the rain clutter adjustment method
1. Press the MENU key to open the menu.
2. Use

or

to select [Echo] and press ENTER .
3. Use

or

to select [Rain Mode] and press ENTER .
4. Use

or

to select [Auto] or [Manual] then press the ENTER key. The window
for Gain/Sea/Rain indicator appears (see the figure on the step 4 of section 2.10).
SEA control adjusted;
sea clutter reduced
Sea clutter at
screen center