On a recent flight, with the GTN 750 Xi zoomed out to show a 200-mile range ring, I saw another ring the meaning of which I don’t know. I didn’t see a reference to it in the manual. Does anyone know what this ring is showing me?
It only shows that extra ring if you've configured the GTN to display a mix of regional and CONUS weather received from FIS-B.
If you select one or the other, it'll go away.