154 E-Series Networked Display Reference ManualManual (MAN) modeIf you do set the TUNE function to MANUAL, you will need to adjust it about 10 minutesafter you have turned on the radar, since the required setting will change after themagnetron has warmed up. You should adjust the control to obtain the maximumsignal strength (indicated by the eight step horizontal bar.). If you cannot tune theradar successfully, refer to the Installation Guide.FTCYou can use the Fast Time Constant (FTC) function to remove areas of clutter at adistance from your boat or to distinguish between two very close echoes on the samebearing, which may otherwise merge and appear as one echoWhen the FTC function is turned up, only the leading edge of large (rain clutter) echoesis shown, while the effect on smaller (ship) echoes is only slight. As the receiver is lesssensitive, and background noise and fill-in returns from land and other large targetsreduced, you should turn the FTC function down when its use is not required. Sincestorm cells are usually visible for long distances due to their extreme altitude, you maywish 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.RainYour radar detects echoes from rain or snow. The strength of these echoes is dependentupon the altitude, range, density and size of the snow flakes or rain droplets and willappear on screen (seepage 145) as countless small echoes continuously changingsize, intensity and position.Turning the RAIN clutter function on suppresses the bulk effect of rain returns fromaround your boat, so that detection of actual targets is made easier.Using the enhance echoes functionsYou can improve visibility with the enhance echoes function.Interference RejectionONThe interference rejection function, which is normally left switched on, automaticallyreduces any mutual radar interference when two radar equipped vessels are operatingwithin range of each other (seepage 145).To change the interference rejection setting:
