Raymarine RL80CRC PLUS, Chartplotter RL70CRC PLUS manual Merge and appear as one echo, Bad weather

3-10 hsb2 PLUS Series Color LCD Display

O

as large hazy areas, depending on the intensity of the rainfall or snow in the storm cell.

The RAIN and FTC controls are used to reduce this clutter, so that targets masked by the clutter can be seen on the radar picture.

Adjusting Gain, Sea Clutter, Rain Clutter and Tune

F

F • The RAIN control is used to reduce large clutter masses around your vessel caused by rain or snow.

RAIN

•The FTC (Fast Time Constant) control is used to reduce rain clutter at a dis- tance from your vessel, such as that shown below.

D3967-1

Figure 3-8: Rain Clutter

When the FTC control is turned up, only the leading edge of large (rain clutter)

Oechoes is displayed, while the effect on smaller (ship) echoes is only slight.

F	This means that you can also use the control on shorter ranges to distinguish
F
	between two very close echoes on the same bearing, which may otherwise
FTC	merge and appear as one echo.
	When the FTC control is turned up, the receiver is less sensitive, and there is a
	reduction of background noise and fill-in returns from land and large targets.
	You should therefore turn the control down when its use is not required. Since
	storm cells are usually visible for long distances due to their extreme altitude,
	you may wish to leave them displayed so that you can observe the location of
	bad weather.
	If you turn the RAIN or FTC control Off (equivalent to setting the level to 0%),
	the actual setting is stored, and restored when you turn the control on again.
	Note: RAIN and FTC are reset to Off at power-on.