The end of analog TV is coming, and it's something we'll be talking about a lot between now and next February 17.

That's the date set by federal mandate for full-power U.S. television stations to switch off their analog transmitters. If you have an older TV set — and if you receive your local stations off the air via "rabbit ears" or an attic or rooftop antenna — you won't see anything after early next year unless you take action.

Fortunately, all you need is a simple "converter box" to pick up the new digital signal and reformat it to make it suitable for older "analog" TVs.

Digital TV converter boxes are available from a variety of retailers, including Best Buy, RadioShack and Circuit City, and are priced under $60. You can also get up to two $40 coupons from the government to subsidize your switch (more on that later).

But I'm hearing from some viewers who purchased a converter box, plugged it into an indoor antenna and don't see any digital picture on some stations.

I asked Consumer Electronics Association spokesman Jim Barry about that issue. "We're talking about off-the-air signals here. Whether they're analog or digital, there is the potential for some interference," he said. "What is possible is what they call the 'cliff effect.' When you get out to the end [of a TV station's coverage area], you don't get ghosts and snow, or a gradually degrading picture — the picture just disappears."

In some cases, you may need an outdoor TV antenna to get the best possible reception on all local channels. Some models are designed to that you can install them in an attic area.

There is a potential, but probably short-term problem for some people who are trying to make the switch to digital TV: Some viewers have told me they are having a hard time finding the necessary converter boxes.

After visiting a number of local retailers, I can confirm that they're often not easy to find. The shelves were bare at several of the stores, including Wal-Mart and Target — both of which had been carrying two different models of converter boxes.

While I expect that the supply situation will resolve itself well before the February 17 deadline, there could be a problem if you're holding a $40 instant rebate coupon because the coupons expire 90 days after they are issued.

You'll find a growing list of retailers who are authorized to process the coupons online or by telephone here:

•  TV Converter Box Program Web site

There's been some talk in Washington about extending the valid time for the coupons, or perhaps letting consumers with expired coupons re-apply, but there has been no ruling on that so far.

We've tried to answer all your questions about the digital TV transition on our special page devoted to the topic:

• WFAA Digital Countdown

We've been busy making improvements and enhancements to Channel 8's Web site.

This week, you'll notice a subtle but important change to our popular video clips. If you look down in the lower right-hand corner of the clip as it's playing, you'll see a small icon that lets you expand the image to full screen. Previously, clips would play only in a window on the Web page.

Yes, this is something you've been able to on YouTube and other sites for a while now, but it's a welcome addition to WFAA.com that really helps turn video clips into something more like TV on demand.

In fact, if you can connect your computer to your TV set, it is TV on demand. Give it a try!

•  WFAA.com Video on Demand

Note: The "full-screen" function was disabled for technical reasons after our report aired; we expect it will return soon

Click on our Traffic section and you'll find a new option: Traffic Cameras.

It's a full-screen Dallas map with little camera icons wherever there's a Texas Department of Transportation camera (and there are a lot of them!).

Click on the map to zoom in; click on a camera to get a fresh picture from that location.

You'll want to bookmark this page if you drive in the Dallas area; it's great to check before hitting the road.

•  WFAA.com Traffic Cameras

We know that sports is important to many of our WFAA.com visitors, so we've beefed up our online coverage with a Sports Blog featuring reports from our mobile journalist, Aaron Chimbel.

This week, Aaron is also contributing video reports from Cowboys mini-camp at Valley Ranch, including news conference clips and interviews with key Cowboys personalities throughout the day.

And don't forget that WFAA.com is also the place to watch replays of Dale on The Hour of Hansen radio program along with an archive of archive of our weekly High School Sports Special.

•  WFAA.com Sports
•  WFAA.com Sports Blog
•  The Hour of Hansen

Finally, I'd like to call your attention to WFAA.com's Desktop News. It's a link just under the main story on the home page. Click to launch a mini-version of WFAA.com, with always-updated headlines, weather and traffic information in a tidy window that you can leave open while you view other Web sites (or just try to get some work done).

•  WFAA.com Desktop News

Watch Computer Corner every week on News 8 Midday at noon Wednesdays, or online any time.

E-mail askwalt@wfaa.com