A alternative, but only for timing and as GPS supplement. Unless you’re in a place where you can pick up 4 ATSC transmitters at different locations you won’t get position or navigation with it.
So if you can get more than 3 different TV stations you should be good. Most stations don’t share transmission towers, AFAIK.
There are places, especially in the mountains where you don’t get the requisite number of towers, but large portions of the US will, and the required signal to noise ratio is better than to decode regular TV signals, so you have a larger area covered than for TV.
