It's nearly impossible to buy a TV today that isn't a high-definition set. But just because the set is an HDTV doesn't mean you're actually watching a high-def picture. In addition to an HD-capable TV, you need an HD programming source. Your cable or satellite company will be happy to upgrade you to high-definition, though in most cases you'll pay for the privilege. On the other hand, when it comes to network TV, you can watch with no additional fees at all, thanks to over-the-air HDTV.

A simple antenna may be all you need to get free HDTV reception. — Noah Webb/Getty Images

The over-the-air advantage

All the major networks and many local stations broadcast hours of programming in high-definition every day, at no charge. Not only do you get a sharper picture with high-def than tried-and-true standard definition, you also get a much larger image. The full wide-screen picture fills the HDTV panel, instead of sitting in the middle with bars along the left and right edges like a standard-definition picture on an HD set.

In fact, the picture quality for free broadcast HDTV is actually better than what you'd get from your cable or satellite provider's high-def service. Cable and satellite have to compress their signal to transmit the hundreds of channels they offer, and this inevitably hurts picture quality. Broadcasters have plenty of room in the digital spectrum they've been assigned to send out a much better-looking picture. In fact, many stations broadcasting HDTV have so much available space that they've added additional sub-channels to their offerings.

TV listings for free

The first question to ask is what's available for you to watch on free HDTV? You'll find the answer at the TitanTV.com website. Here you'll enter your ZIP code, ask for the broadcast TV listings (versus cable or satellite) and you'll get an easy-to-read grid displaying all the over-the-air programming in your area, with a bright red "HD" next to the high-definition shows (even if a station offers HD service, that doesn't mean every program is in HD).

Next: Swap the cable box for an antenna. >>