Digital TV arrives: what you need to know

Finally, after years of waiting, a four-month extension and hyped-up attempts to sell everything from cable TV service to new antennas, the switch to digital television comes at midnight Friday. • For most of you, this change won't mean much. According to Nielsen Media Research, just 3.5 million households remain completely unready for the elimination of analog broadcast TV signals. • But it bears repeating: If you have cable or satellite service, you don't need to do anything. If you get television through an antenna, you either need a TV capable of displaying digital signals or a digital-to-analog converter. • To get a sense of exactly what people are up against, I tested two versions of a digital-to-analog converter: the Digital Stream DTX9950 ($59.99) and Zenith's DTT901 ($60). Both are eligible for the government's $40 coupons to help cover costs. Here's what I learned:

You may not need cable.

Both units produced a picture clearer than most analog broadcasts, with access to subchannels offered by local broadcasters. NBC affiliate WFLA-Ch. 8, for example, has 8 Prime, a secondary channel with old TV shows, while WMOR-Ch. 32's offers a lineup of old movies on its This TV channel. There are about 30 channels available in all, with PBS stations WEDU-Ch. 3 and WUSF-Ch. 16 offering four channels each.

You may not get all the channels you're used to.

Both units had trouble picking up all the area's broadcast channels using a $30 RCA digital flat antenna. At work, I couldn't access WFLA or WTSP-Ch. 10's digital channels; at home, the access was better, but still problematic. I also got different sets of signals by placing the antenna at the front of my house or the back (digital signals don't travel as well as analog signals and may come from different transmitters). I did, however, pick up Sarasota ABC station WWSB-Ch. 40 and Fort Myers' NBC affiliate WBBH-Ch. 2, so there's that.

Converter models matter.

The Zenith unit offered a better overall experience: cleaner picture, better onscreen graphics, a user-friendly onscreen programming guide and more channels captured. The Digital Stream, provided by RadioShack, took longer to warm up, captured fewer channels and took longer to scan for channels. And though digital frequencies generally come in or don't — no snowy picture — you can get pixilated or frozen pictures if the signal isn't strong enough.

Broadcasters need more digital offerings.

The PBS stations have led the way here, with kids' channels, Spanish-language channels and legislative channels among their digital offerings. But Fox station WTVT-Ch. 13 just rebroadcasts its regular signal on its secondary digital channel, while WTSP and Tampa ABC station WFTS-Ch. 28 have 24-hour weather channels (zzzzzz!). Broadcast DTV could be a cheaper cable alternative for viewers; spend $100 for a converter and set-top antenna and you're set. But the programming needs to be there.