They're all digital now and, usually, each channel's xx.1 main channel is HD and any subchannels (xx.2, xx.3, etc) are SD. They seem to use the most bandwidth per channel to their "main" channel and spread the rest of the bandwidth between SD channels, like weather, Grit, MeTV, and other "nostalgic" channels (lots of John Wayne, Batman, Gilligan's Island, etc.).
If a station decides it wants to broadcast TWO HD channels, they'll cut down the bandwidth to each so they both fit in each channel's max. bandwidth. I've got an ION station that has a main HD channel and 5 SD channels, incl. SHOP, QVC and HSN.
YMMV, but you can be pretty much assured that however many main channels show up in TVFool for your locale, those will most likely be digital/HD.
Last edited by 7558037; 12-10-2014 at 01:47 PM.