Furuno FR-8062 Suppressing Rain Clutter, Manual sea clutter adjustment, Appearance of sea clutter

1. OPERATIONAL OVERVIEW

1.11.3Manual sea clutter adjustment

1.Push the A/C SEA control to show “SEA MAN” as the A/C SEA adjustment method.

2.Rotate the A/C SEA control to suppress sea clutter.

The proper setting of the A/C SEA control is such that the clutter is broken up into small dots, and small targets become distinguishable. If the setting is set too low, targets 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.

Sea clutter at	A/C SEA control adjusted;
screen center	sea clutter suppressed

Appearance of sea clutter

1.12Suppressing Rain Clutter

The vertical beamwidth of the antenna is designed to see surface targets even when the ship is rolling. However, by this design the unit will also detect rain clutter (rain, snow, or hail) in the same manner as normal targets.

The A/C RAIN control adjusts the receiver sensitivity as the A/C SEA control does but rather in a longer time period (longer range). The higher the setting the greater the anti-clutter effect. When echoes from precipitation mask solid targets, adjust the control to split up these unwanted echoes into a speckled pattern, making recognition of solid targets easier.

1.12.1Choosing rain clutter adjustment method

Rain clutter may be adjusted automatically or manually. Push the A/C RAIN control to choose automatic or manual adjustment alternately. The adjustment method currently chosen is show at the top right corner of the screen. In the example below the rain clutter adjustment method is “AUTO.”

TUNE AUTO

GAIN AUTO

SEA AUTO

A/C RAIN adjustment method (AUTO) RAIN AUTO

A/C RAIN indicator

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