162
E-Series Networked Display Reference Manual
Gain
The gain function makes the radar picture clearer by changing the sensitivity of radar
reception.
•
For long ranges
- select a sensitivity level that gives a slight speckle in the back-
ground. Be careful not to set the gain too low, or you may miss weak or small tar-
gets.
•
For shorter ranges
- reduce the gain slightly to reduce the speckle and therefore
improve target definition.
Note:
If you set the GAIN to MAN (manual), you should check it every time you change
the range scale.
FTC
You can use the Fast Time Constant (FTC) function to remove areas of clutter at a
distance from your boat or to distinguish between two very close echoes on the same
bearing, which may otherwise merge and appear as one echo
When the FTC function is turned up, only the leading edge of large (rain clutter) echoes
is shown, while the effect on smaller (ship) echoes is only slight. As the receiver is less
sensitive, and background noise and fill-in returns from land and other large targets
reduced, you should turn the FTC function 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.
Note:
Use FTC in conjunction with the RAIN function to obtain the best picture.
Rain
Your radar detects echoes from rain or snow. The strength of these echoes is dependent
upon the altitude, range, density and size of the snow flakes or rain droplets and will
appear on screen (see
page 153
) as countless small echoes continuously changing
size, intensity and position.
Turning the RAIN clutter function on suppresses the bulk effect of rain returns from
around your boat, so that detection of actual targets is made easier.
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