I posted this as a response to a comment on one of my other articles, but I thought that this information deserved an article all to itself. The original question posed by the commenter was:

BTW, does any one know how long i can go with rabbit ears? will the change to HD ruin that?

My Answer:

In Februrary 2009 (I believe is the cutoff), the FCC has mandated that all television stations cease transmitting their current signal. At that point, they will only be allowed to transmit a digital signal. Many of these signals will be high definition (HD) and some will be standard, or enhanced definition (SD, ED), but all will be digital.

Likewise, the spectrum that is currently used for VHF transmissions (currently the lower numbered channels 2-13 I think) will be abandoned and auctioned off to bidders for other uses. Digital television will all be transmitted in the UHF spectrum. Most antennas these days (rabbit ears or big attic antennas) have both a VHF and UHF capability. UHF currently is all our high-number channels (14-62 I think). On rabbit ears, the UHF antenna will often be in the shape of a loop.

So, a UHF antenna will be required to pick up the digital (SD,ED,HD) signals starting in 2009. Most antennas already handle it. If you go to stores like BestBuy, you'll see HD Antennas. All this is is a UHF-only antenna. Nothing special about it other than marketing.

The thing that will cause you more pain is that, unless you already have a brand new TV, your TV will not be able to handle the digital signal. You'll either have to upgrade TVs to one that has a digital tuner in it, or purchase a converter box (sometimes called an HD set top box). The box would work like a cable or dish box, but for your OTA transmissions. I believe the government is making available $40 vouchers (2 per household) that you could use toward the purchase of converter boxes.

Also remember that if you keep your standard TV, you won't be getting the most out of the HD signal. The set top box will basically downgrade the signal to work on your TV. You might get a little more clarity from the digital signal, but you won't get HD without an HDTV.

Hope that answers your question.