A change is coming to television and it's not a new reality show about supermodels racing go-carts in the Gobi Desert.

It's broadcast digital television and you've probably already heard about it (at least if you read TechMan you have).

On Feb. 17, 2009, television stations will have to stop broadcasting analog signals over the airwaves, replacing them with digital signals.

What's it mean to you?

If you have cable or satellite television, it means nothing. If you get your television over the airwaves (with an antenna) and your TV already has a digital tuner, it means nothing.

To see if your set has a digital tuner, check the manual for a built-in Advanced Television Systems Committee (ATSC) tuner. Or check the manufacturer's Web site.

However, if you are one of the estimated 19.6 million households that get TV over the airwaves but don't have a digital-ready TV, after Feb. 17, 2009, you have three choices: get cable or satellite service, buy a new TV with a digital tuner or buy a converter box.

There is some good news here. Congress has set up a program to help you buy a converter box. If you call 1-888-388-2009, you can request coupons for two boxes worth $40 each. Since the boxes are estimated to cost $50 to $70 depending on features, you may have to shell out a little more money. The coupons must be used within three months.

So why get a converter box now? TV stations are already broadcasting in digital and that means better picture and better sound. If you have an HDTV set you can get a good high-definition picture over the digital airwaves.

There's just one problem. Once you get your coupon, at least for now, you can't find a converter box.

A colleague of mine tried the Web sites of eight national chain stores and could not find a box for sale, although they should become available in a month or two.

So why is all this being inflicted on us by the Federal Communications Commission? As you might guess, one of the reasons is money, big money. Billions.

When television stations stop broadcasting analog signals, which take up a lot of "room" on the airwaves, "prime real estate" on the 700 MHz band becomes available for the FCC to auction off.

This is desirable bandwidth because it travels through walls and is long-range.

On Thursday, the FCC begins to sell off this bandwidth, although big chunks are blocked off for public safety communications.

But what's left is a gold mine. The first block of 12Mhz, for example, which represents analog channel 52, has 176 licenses to sell.

So what are these licenses good for? Cell phone service and wireless Internet and other data services are possibilities. And how about video? After all, this was the television spectrum.

Who is going to win big at the auction? Well, Google has lots of money. But a lot of bets have been placed on Verizon, which recently announced that it would allow any phone to be used on its cellular network, not just phones it sold. Coincidentally, this "device independence" is a requirement for use of bandwidth purchased in the auction.

So pay attention to the auction. The outcome could mean big changes in what comes to you through the airwaves.