Furuno FAR-1416, Руководство оператора

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1. OPERATIONAL OVERVIEW
1-25
1.19.3 How to manually reduce sea clutter
The A/C SEA control reduces the amplification of echoes at short ranges (where clut-
ter is the greatest) and progressively increases amplification as the range increases,
so amplification will be normal at those ranges where there is no sea clutter.
The proper setting of the A/C SEA should be such that the clutter is broken up into
small dots, and small targets become distinguishable. If the setting is set too low, tar-
gets will be hidden in the clutter, while if the setting is too high, both sea clutter and
targets will disappear from the display. In most cases adjust the control until clutter has
disappeared to leeward, but a little is still visible windward. Be careful not to remove
all sea clutter, because you may erase weak echoes. Further, the possibility of losing
weak echoes is greater when you use both A/C SEA and A/C RAIN to reduce clutter.
How to reduce sea clutter manually from the control unit (RCU-029)
Rotate the AC/SEA knob ( F3 ). Rotate anticlockwise to decrease the AC/SEA, or
clockwise to increase the A/C SEA.
How to reduce sea clutter manually from the on-screen box
1. Select [SEA MAN], following the procedure in paragraph 1.19.1.
2. Place the arrow in the A/C SEA level indicator at the top of the display.
3. While observing the A/C SEA level indicator, rotate the
scrollwheel downward to
increase the A/C SEA or upward to decrease it. The setting range is [0] to [100].
1.20 How to Reduce Rain Clutter
Use the AUTO RAIN and A/C RAIN to reduced rain clutter. AUTO RAIN reduces rain
clutter in the picture and A/C RAIN reduces clutter picked up by the antenna.
Note 1: When both sea clutter and rain clutter are reduced, the sensitivity is de-
creased more than when only one is changed. For that reason adjust them carefully.
Note 2: The echo average (see "Echo Averaging" on page 1-28) is useful for reducing
reflections from the sea surface. However, high-speed targets are harder to detect
than stationary ones when the echo average is active.
1.20.1 How to select the method of rain clutter reduction
Select the [RAIN] indication at the top-right of the screen, then press the left button
to toggle [RAIN(A)] (automatic reduction) and [RAIN(M)] (manual reduction).
Sea clutter at
screen center
A/C SEA control adjusted;
sea clutter reduced
RAIN MAN 70
Left-click inside the box to change the A/C RAIN
adjustment method (RAIN AUTO or RAIN MAN)