/
01.26.2009
Originally featured on BroadcastEngineering.com
Switch to digital TV may not be smooth

Joyce Powell gets a dozen analog channels on her seven-year-old television set. But when she hooked up a converter box to prepare for digital broadcasts, she discovered that she couldn’t receive any local channels, even though the stations’ transmission towers are only a few miles from her apartment building on Wisconsin Avenue in Washington, D.C.

“I thought all I had to do was buy a box and hook it up,” said Powell, 72. “That's what you’re led to believe by all the ads.”

That scenario, the “Washington Post” reported, is going on all over the country. Many Americans are discovering that upgrading to a digital set or adding a converter box is not enough to get a reliable digital signal. Antennas — large, expensive rooftop models — may be required. And even that’s no guarantee reception will be the same.

Last week, Nielsen said more than 6.5 million homes will be unable to receive any full-power digital TV station signals if the DTV transition occurred today. That is the number of homes (5.7 percent of the TV households) that Nielsen estimates are “completely unready” for the DTV switch. That means they do not have a DTV set, an antenna, converter box, cable, or satellite service.

“People are very surprised when they realize they can’t get [the channels],” Barry Goodstadt, an independent analyst who has been studying digital reception issues, told the “Post”. He predicted that 70 percent of households with indoor rabbit ear antennas will have to upgrade to more complex outdoor antennas.

While most viewers are aware the switch is coming due to marketing and public education efforts by federal officials and broadcasters, 75 percent of those who called help lines reported that their converter boxes did not appear to be working.

“We had to say, ‘Your antenna is not powerful enough, or you don’t have one, or it’s pointed in the wrong direction, or the height needs to be raised,’” Connie Book, a professor at Elon University who led students during the Wilmington, N.C. switchover, told the newspaper.

In the Washington, D.C. area alone, about 15 percent of households that rely on over-the-air signals could lose up to four stations with digital signals, Goodstadt’s research shows. About 58 percent of households nationwide are likely to lose one or more channels with current equipment, including rooftop antennas, according to a recent report from the research firm Centris.

Over-the-air digital viewers will discover the cliff effect — the all-or-nothing quality of digital reception. The picture is acceptable until the signal weakens or is interrupted, causing it to disappear completely. Digital signals can receive interference from hills, trees, buildings, bad weather or planes flying overhead.

An analog picture, on the other hand, degrades gradually, getting more static and snow as signals weaken. To complicate the situation, some broadcasters’ digital coverage areas vary slightly from their current coverage areas, so some viewers at the edge of a station’s range will not consistently receive signals.

Goodstadt predicts significantly more viewers will lose signals than the FCC has predicted because the commission assumes houses have stronger outdoor antennas than they do.

DTV could also cause many viewers to adjust the antenna with every channel change. Digital signals need more precise positioning than analog signals.

Cable companies are already advertising low-cost options that allow viewers to avoid all this hassle.


Comments
Post New Comment
If you are already a member, or would like to receive email alerts as new comments are
made, please login or register.

Enter the code shown above:

(Note: If you cannot read the numbers in the above
image, reload the page to generate a new one.)

No Comments Found




Monday 6:39AM
What Price Reliability?
Digitally delivered TV has seen a pile o’ fail lately.


 
Featured Articles
Discover TV Technology