We aren't connected to cable but we used to get channels anyway (with a digital converter box) before we moved. Now that we've hooked it up again in the new house, even with an antenna to help, we can only sometimes get channels, and only two at that, plus they're in Spanish and I don't know Spanish. We did the channel scan. Also, moving it across the house seems to get partial signals from other channels, but still not much luck.
going to have to consider a roof antenna, or an amplified antenna…
http://www.antennaweb.org/aw/welcome.aspx
is a good resource to tell you what you should be receiving from your location, and what types of antenna set ups will help improve what you can view… (a little research on that site will help you purchace or set up the best antenna set up for your needs)
DTV is different than analog broadcasts in, you either get the signal or you don’t… unlike analog where you would at least be able to get a fuzzy image on distant transmitters…