Raymarine E120W, Reference Manual

Page: 170 / 294

154 E-Series Networked Display Reference Manual
Manual (MAN) mode
If you do set the TUNE function to MANUAL, you will need to adjust it about 10 minutes
after you have turned on the radar, since the required setting will change after the
magnetron has warmed up. You should adjust the control to obtain the maximum
signal strength (indicated by the eight step horizontal bar.). If you cannot tune the
radar successfully, refer to the Installation Guide.
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 145
) 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.
Using the enhance echoes functions
You can improve visibility with the enhance echoes function.
Interference Rejection
ON
The interference rejection function, which is normally left switched on, automatically
reduces any mutual radar interference when two radar equipped vessels are operating
within range of each other (see
page 145
).
To change the interference rejection setting: