When the signal drops for any appreciable time, a dialog appears to tell the user that the signal has dropped. Well, it was pretty obvious because we were watching, and the signal dropped. Don’t put up a dialog requiring the user to take an action. If, however, the dialog was going to go away anyway in 10-20 seconds, that would be OK. And, it doesn’t have to be full-screen.
When it gets windy here in the Denver area (like it has been for the last few nights), the signal level varies as the trees, etc. cause the signal levels to vary, causing minor dropouts. The priority should be on maintaining the viewing as much as practical.