It is harder now to pull in distant signals, because you need a line of sight. The old TV broadcast signals moved in a wave fashion, and covered areas in an up and down manner. They could fill in valleys and dips in terrain easily.
The new digital signals are line of sight. You can pull in distant channels, but you better not be blocked by terrain and such.
http://www.antennaweb.org/ will tell you what channels ou are likely to receive, and at what strength. I had hopes of putting an antenna on top of my house and pulling in Cleveland channels for Browns games ..... but I can't do that from here. Even with a super long distance antenna, it doesn't matter. I can get one channel, I believe, from Indiana, or something. Other than that, I can get my locals and that's it. I am in the Mahoning Valley, and even in a relatively high area, I am still in a valley, and that does not bode well for HDTV, digital signals.