If this has been suggested before, please don't read it.  We don't need too much duplication.

I've heard talk of owners efforts to stop the Winegard wandering across the roof of the van during travel.  I checked mine and sure enough, the little foot on the antenna had scribed an arc about 100mm or so long on the fibreglass roof.  I'd rather it stayed still, so I made this little hole for it to drop into and stay in the one place when we move.

The plastic is just a strip cut from a piece of plastic tube.  I didn't have any perspex or rubber handy ... I reckon anything will do.  After cutting the hole with a wad punch I stuck it down flat with a couple of dobs of Sikaflex.  Now even if the antenna doesn't go into the hole when we wind it down, it certainly will the first time it starts to slide from side to side.

Having done the job I now realize that just a strip of something flat glued to the roof in either side of the antenna foot would do the same job.