Government technocrats believe that were it not for them businesses would cheat their customers and resist progress. That’s why the Federal Communications Commission (FCC) is force-marching the broadcast TV industry into the digital age.
I’m not saying the FCC should do nothing. The FCC could have offered carrots to anyone willing to invest in digital TV—leaving the implementation details up to businesses and consumers. Instead, the self-important FCC chose to employ the stick. And that’s why I’m predicting a bumpy transition.
Keep this in mind: roughly 80% of U.S. households already subscribe to pay TV services offered by cable, satellite, and telephone companies. That means only about 20% of U.S. households rely on over-the-air television broadcasts. The FCC’s scheme to revolutionize television bordered on irrelevant before it even started.
The FCC is vaguely aware of potential switchover problems. People who rely on broadcast TV tend to have low incomes. They can’t all be expected to run out and buy brand new digital TVs. Therefore, the government is offering coupons worth $40 towards the purchase of digital TV converters. Quite a few converters are conveniently priced in the $40 range in anticipation of this $1.5 billion act of government largesse.
Unfortunately, a digital-to-analog converter does not guarantee reliable reception of digital TV. Many low income viewers rely on “rabbit ears” antennas. Many have inexpensive and/or older TV sets. And given today’s urban sprawl, many are far from broadcasters’ antenna towers.
Digital signals tend to be an all-or-nothing affair. A weak analog TV signal usually results in a snowy picture. Multipath propagation causes ghost images. Some viewers put up with these annoyances because a lousy picture is better than no picture. With digital TV, however, a weak signal may result in a picture that appears one minute, freezes and becomes pixelated the next, and then disappears (a.k.a. the "digital cliff" effect). Multipath propagation may also prevent digital TV reception; where before there were ghosts, now there is nothing.
Some consumers may purchase converters and find they can only watch certain channels. Others may experience periodic outages when, for example, an airplane passes overhead. In the past, industry groups have forced the FCC to push back compliance deadlines. Perhaps something like that will happen this time. Then again, it may be months before anyone really knows the magnitude of the problem.
One thing is for sure: if a large number of consumers experience problems with the converters there will be no easy fixes. Outdoor antennas will help, but installation could get expensive. Broadcasters may be required to improve their signal coverage, but that will also cost money.
Don’t be shocked if cable and satellite TV subscribers end up footing the bill.
I’m always intrigued when someone finds a novel aspect of something mundane. Almost every household in the U.S. has one or more TVs, and the average American watches more than four hours per day. But how many people know that it is possible to receive stations hundreds of miles away with an ordinary TV?
A small group of people have turned picking up signals from distant TV stations into a sport. It’s called TV DXing. (“DX” stands for “distant.”) Many TV DXers are amateur (ham) radio operators; some also hunt distant AM and FM radio stations. There is even a Worldwide TV-FM DX Association. The record for VHF reception is over 10,000 miles (when a British TV station was received in Australia); UHF DX distances are much shorter.
Successful TV DXing is mainly a matter of knowing when (time of year/time of day) and where (over-the-air channels) to look. It is possible to receive TV stations from other cities using a “rabbit ears” antenna. However, a directional rooftop antenna with a rotor will do even better. There are also plug-in cards that add analog and even digital TV reception to PCs, making it easy to capture, store, and share images from distant stations.
Here are some screen shots provided by St. Louis area TV DXer Eric Bueneman (amateur radio callsign NØUIH):
What makes TV DXing possible? The FCC assigned the VHF and UHF bands to FM radio and television because signals at these frequencies normally do not travel long distances. However, certain atmospheric conditions enable the signals to travel much further than usual. The three main sources of DX propagation are sporadic E, tropospheric ducting, and meteor burst.
Sporadic E propagation occurs when signals reflect off patches of highly ionized gas in the E layer of the ionosphere. It is less common than skywave propagation, which accounts for worldwide shortwave reception, but it affects higher frequencies.
Tropospheric ducting is the result of atmospheric temperature inversion and causes signals to bend (refract). It is most common in the summer and fall and typically enables signals to tunnel through the atmosphere up to 800 miles.
Meteor burst occurs when signals bounce off ionized gas trails left by meteors. Tiny meteors collide with the earth's atmosphere almost constantly. Propagation may last from as little as a fraction of a second up to several minutes. (Believe it or not, during the early 1990s at least one company offered meteor burst communications for long-haul truck fleets.)
The conversion to digital TV will affect TV DXing. Say good bye to TV channels 52-69, which are being reallocated to other services. DXers should be able to capture more perfect or near-perfect video frames, but digital transmission (which tends to be an all-or-nothing affair) is more intolerant of multipath propagation.
I believe the FCC’s forced march to digital TV could be a big problem for consumers using “rabbit ears” antennas for local reception, and that will be the subject of my next post.
The history of science and technology is riddled with claims and counterclaims regarding discoveries and inventions. Today's Wall Street Journal features this front page article: Alfred Russel Wallace's Fans Gear Up for a Darwinian Struggle. The claim is that Darwin stole many key ideas about evolution from Wallace.
History usually does a good job sorting out priority. The biggest problem is that people confuse thinking of an invention (or theory) and making it happen. Sure, Darwin borrowed ideas from others, but he put them together in a more convincing package. And Alexander Graham Bell fought off no fewer than 600 challenges to his patents as he and his partners transformed his simple device into a thriving business.
Inevitably, some people's thinking evolves from "Why didn't I think of that?" to "I did think of that." As I describe in my book, The History of Wireless: How Creative Minds Produced Technology for the Masses, Charles T. Jackson claimed he and not Samuel F.B. Morse invented the telegraph. Jackson also claimed it was he and not William T.G. Morton who was first to conceive the use of anesthesia in surgery. Another prolific retroactive inventor was Daniel Drawbaugh; he waited until 1880 to announce that he invented the telephone years earlier. He resurfaced in 1903 claiming he, not Marconi, invented radio.
James Gleick’s bestseller Chaos: Making a New Science was published more than twenty years ago. The book introduced the public to an intriguing theory, the mavericks who pioneered it, and some of its most promising applications. So where does the new chaos science stand?
Gleick’s book is interesting and well-written, but I found it unsatisfying. The use of the word “chaos” is misleading. Chaos implies a total lack of order; the phenomena described in the book are all deterministic. In fact, some people call it “deterministic chaos.” Sounds like an oxymoron to me.
Near the end of the book Gleick admits that some of the researchers he portrayed are themselves uncomfortable using the word “chaos.” The systems they study appear to behave randomly only because they are extremely sensitive to small perturbations in initial conditions. That’s true for systems that are either complex or simple and nonlinear.
Don’t get me wrong. I’m not against studying systems that are complex or nonlinear. Some of my best friends are complex or nonlinear.
What bugs me is that Gleick and others use the word “chaos” simply for its mystique. I guess we are supposed to imagine that chaos theory transcends ordinary science and discovers higher truths. Still, I’m willing to cut the chaos kids a little slack. Brochures present products in their best light and resumes do the same for job seekers. Why shouldn’t complex/nonlinear system researchers toot their own horn?
What worries me is that chaos theory promises to revolutionize important applications such as diagnosing and treating heart arrhythmia--but mainly delivers more research proposals. I realize that fractals—which have many practical applications—are now associated with chaos theory, but the mathematics underlying fractals has been around a long time. Chaos theory also promises advances in such far-flung fields as economics, meteorology, and ecology; good luck with that!
An article in Complexity Digest suggests that chaos theory “inspired” development of a method for predicting epileptic seizures. No one can argue with that claim. But it boils down to searching for and finding patterns amidst what appear at first to be random fluctuations. Isn’t that called “pattern recognition”?
It’s hard to trust a science with a misleading name. Particularly when there is so much taxpayer-funded research.