Three public TV stations plan to experiment with digital transmission

Originally published in Current, Aug. 5, 1996

By Steve Behrens

While most TV broadcasters wait uneasily to hear what channels they'll get for digital transmission, three public TV stations are rushing to go digital within a few months. WETA in Washington received its experimental transmission license July 26 [1996]; Seattle's KCTS and Oregon Public Broadcasting expect the FCC to issue their licenses soon.

The three pubcasters last week announced a Digital Broadcasting Alliance for cooperation in the experiments, and PBS committed to provide a high-definition satellite feed by this fall, several hours a day, to support the experimental stations. [By November, WMVS/WMVT in Milwaukee and WGBH in Boston joined the alliance.]

Experimental transmitters at two commercial stations already are on the air--as of July 23 at CBS affiliate WRAL in Raleigh, N.C., and as of July 31 at NBC-owned WRC in Washington, D.C.

It's worth noting that Jim McKinney, manager of the TV industry's model station at WRC, currently claims to possess what may be the world's only TV set capable of picking up a digital broadcast. And the experimenting stations are scrambling to find rare prototypes for the requisite chain of transmission equipment.

But the digital future is coming up fast. The FCC will soon issue its first official table of allotments, and if it sticks with its timetable, some DTV stations (as the commission now calls them) will start operating next year and all the rest by 2000.

The FCC began its last big step toward DTV on July 25, announcing plans to pack most of the digital transition stations between Channels 7 and 51, a tighter fit than previously proposed. When the commission publishes its table in the next few weeks, broadcasters will be interested to see how FCC engineers did it.

By narrowing the TV band, the government will be able to auction off Channels 2-6 and 52-69--a total of 138 MHz that the portable telephone industry yearns to acquire. The commission also contends that Channels 7-51 are technically best suited for digital transmission.

Proceeds from the auction "could be used for many purposes, including rebuilding schools and funding PBS,'' FCC Chairman Reed Hundt said in his statement about the rulemaking. Some of the channels also could be retained to provide a common band for police and other public-safety communications, he suggested. Hundt made the same points in a letter to House telecom subcommittee leaders and in a speech to the Public Radio News Directors conference July 26.

Packing in the channels

With these developments in the air, public television's DTV planning efforts are accelerating. Public TV's digital enthusiasts met last week in Denver with the PBS New Technology Working Group and members of CPB's Television Future Fund advisory panel.

Seven applicants for Future Fund grants described their proposals and caucused to coordinate plans and prevent redundancy, says CPB staffer Doug Weiss. The advisory panel already sees a need for all of the proposed research projects, and most will be approved within a month or so, he predicts. The hazier projects will be refined. Altogether, Weiss expects the TV Future Fund to spend $1 million to $1.5 million of this year's $6.4 million on DTV projects.

Several who attended the Denver meeting came back saying they hope public TV stations make a coordinated response to the FCC's forthcoming channel table.

"If it's every station for ourselves, we'll lose out in most markets," says Jim Kutzner, v.p. for operations and engineering at KTCA in Twin Cities, who is asking CPB to underwrite a DTV coordination office for public TV.

Because the table represents a complex matrix of decisions weighing coverage and interference, one station requesting a change in the plan can set off ripples of consequences for others. It takes a fast computer 17 days and nights to run a model of the channel allocations, according to Harvey Arnold, associate director of the University of North Carolina's statewide network, who works with PBS and the national networks' Broadcast Caucus.

Deluging the FCC with uncoordinated, conflicting complaints from every market in the country could cause the FCC to delay the DTV timetable, and the commission or Congress could turn to lotteries or auctions to hand out DTV channels, warns Burnie Clark, president of KCTS, Seattle. Having the temporary channels for the digital transition is a valuable opportunity, he says. "I'm not sure broadcasters recognize what's being offered here."

Opponents of the DTV transition plan, including the People for the American Way Action Fund, call it a "$40 billion spectrum giveaway," and presidential candidate Bob Dole periodically makes similar charges.

Broadcast engineers are taking a wait-and-see approach toward the FCC's proposed channel table. After it's published, stations will have about 90 days to make their first round of comments, expects Marilyn Mohrman-Gillis, v.p. of America's Public Television Stations. Under the FCC's draft timetable, it may start accepting license applications next winter and stop accepting them early in 1998, giving licensees two years to get on the air--by 2000.

PBS plans a videoconference about DTV in September and will organize detailed discussions of the subject at its Fall Planning Meeting in November.

Mark Richer, former PBS v.p. for engineering and computer services and now executive director of the Advanced Television Systems Committee, the inter-industry organization that helped bring together the FCC's standard for digital transmission, withholds premature judgments about the table.

However, he does say that minimizing broadcasters' use of 23 channels at the top and bottom of the present TV broadcast bands, as the FCC table aims to do, "definitely won't be helpful" in giving stations good coverage and protection from interference.

The commission says it aims to make sure that all existing TV broadcasters get DTV channels that replicate their current service areas and that minimize interference among digital and analog stations. Neither the new DTV signals nor the existing analog signals will be given automatic preference in resolving interference, the commission said.

To pack in all those active broadcasters, the commission proposes to delete all vacant allotments of channels to specific regions, though it said in the case of noncommercial allotments it would try to provide new DTV channels.

Hundt said the commission's new channel plan offers only 1.4 percent less replication and 7 percent more interference than an earlier broadcast-industry proposal that made more use of top and bottom channels.

The relatively few stations now using the upper channels won't be "harmed," the FCC said. And some new DTV channels may be assigned in the 50s and 60s in regions where no lower channels are available.

Some translators in jeopardy

If anyone is harmed or inconvenienced, it will probably be the operators and viewers of the 5,000 television translators in the country, which extend the signals of distant stations by "translating" them to another frequency and rebroadcasting them. Those include some 775 translators tied to public TV stations, says Harvey Arnold in North Carolina.

Most translators are in rural areas where channels aren't congested and will be okay, Mohrman-Gillis predicts. FCC staffers tell her that 85 to 90 percent of translators will be unaffected. But the FCC gives full-power stations priority in cases of interference, and some translators and low-power stations will lose their frequencies when DTV channels are established. Others will be displaced because they're camping on vacant channel allotments that the FCC plans to use for DTV.

One hope for some of those translators, Richer speculates, is that DTV technology may allow signal extension by repeaters that use the same channel as the main transmitter. Digital receivers will have such effective ghost-canceling chips that the repeating transmitters won't have to use different channels, as analog translators do.

That may work, but only in areas where the translators are hidden from same-channel signals by high terrain, Arnold theorizes.

Why rush to try it out?

WETA is aiming to put a digital signal on Channel 34 in time for its 35th anniversary in October, says Joe Widoff, senior v.p. for operations and administration. KCTS plans a small 1,000-watt transmitter, aimed largely east in the direction of Microsoft and Seattle's other high-tech centers. OPB also hopes to put a Portland transmitter on the air by some time next year.

The three pubcasters hope to use experimental stations to promote not only the digital transition in general but also their own campaigns to rebuild their technical facilities. The D.C.-area station is building new facilities anyway for its new building in Arlington, Va., and has opted to make it the first public TV site ready for HDTV and digital transmission.

For Oregon, the experiment will give donors concrete evidence that digital TV is "real," and that the network needs $23 million to build a statewide digital transmission system to operate alongside and then replace its five-transmitter analog system, according to OPB President Maynard Orme. The campaign is already underway with big donors.

Orme is certain the TV world is going digital. "So I want to be an early adopter. I want to be out there with my digital signal so if people have their sets, they come to me first. They're going to say, 'OPB's got it.' "

To build public and political support for digital TV, and particularly for funding the hardware public TV will need to buy, it will be important to put HDTV receivers in public places and where politicians see them, says Clark. PBS is seeking CPB funding for a road show that would take HDTV demos to stations around the country.

But the electronics industry hasn't accepted past PBS proposals for public demos. Model HDTV Station Project, the industry-sponsored experimental station at WRC in Washington, doesn't plan to set up viewing sites around the region until 1998, says McKinney. "The consumer manufacturers are not anxious to have us do widespread public demonstrations when they don't have anything to sell to the public," he explains.

That may be true of manufacturers that already are in the TV business, with huge stakes in existing NTSC hardware, but it will only take one company that wants to break into HDTV to cause the whole industry to turn up the publicity machine, Clark predicts.

Orme admits that he also has a personal reason for jumping into the new generation of TV technology when many of his peers are dreading the prospect.

Decades ago, when he was a kid, he saw his first TV picture in a store in Philadelphia. It was just four by three inches and quite disappointing, compared to the big, clear screen he knew from movie theaters. Then, in 1986, he saw his first HDTV image. "At last--the way television should be seen at home," he says. "That was exciting to me, and I'm driven a lot by that."

Knowing the details

Perhaps the most concrete gain from the experimental stations may be learning in detail how to build a digital station and put it on the air.

"We're going to learn a lot,'' predicts Clark. "We're going to build our expertise and share it with others."

This practical work will run parallel with studies by major inter-industry bodies to develop technologies and standards for the many missing links of a digital broadcasting station.

The Advanced Television Systems Committee, midwife of the FCC's digital transmission standard, where Richer has been executive director since March, will work to develop standards for signal distribution within stations, for network feeds to stations, and for over-the-air data transmission, among other things. ATSC will work with other industry bodies, including the Society of Motion Picture and Television Engineers and the Electronic Industries Association.

At the same time, the industry-supported Advanced Television Technology Center next door to PBS in Alexandria, will do lab work to test and develop these kinds of technologies. Howard Miller, retired senior v.p. from PBS, is now heading ATTC.



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