OTA or over the air is not a sure thing. That is, one you you'll get a certain channel and the next you may not. I'm finding folk that need to discuss this, antennas and a few that can't figure it out need to get cable TV.
I have an LG 26LV2500 and I am always having to scan for channels it seems to just skip from 12-17 after turning it off a couple of times and then I have to scan again. I tried manually adding the channels but when I did that it just made the channels turn to static.