I was having a problem with GATTRS reception in the Round Rock/Pflugerville area. I could receive the Williamson and Bastrop Counties sites, but not Austin. This started after I moved the side table from one side of my recliner to the other. That's about 2 1/2 feet. Before the move I could get all three sites pretty well using the Remtronics 800 MHZ antenna.
Such is simulcast.
I finally ordered a Comet Miraclebaby and that fixed the problem. Not perfect and I may end up moving my SDS100 from room to room, but it's a lot better.