It seems that when on Auto mode, the side lobe that produces the false echo at a pseudo distance equal to the height of the aircraft is removed, whereas in Manual mode, it is not.
Could someone explain if this makes sense and if yes why ? I.e. what would be the difference in Auto mode regarding de cluttering of the return of the side lobe as opposed to Man mode?
Also, the false echo seems to get worse if the radome is wet, or in bad shape, or covered with ice, or not fully adjusted correct?
What could be done to remove or diminish this phenomenon, even on a brand new aircraft ?