Digital television and public television

This Current Briefing page gives you access to pertinent stories from Current.

Primer: the headlong rush toward improved TV
How did DTV come to be?
How will public TV pay for the transition?
How will the technology be used?
What about radio's transition to digital?
Links to DTV-related web sites



Primer: the headlong rush toward improved TV

To the viewer, America is not moving TV very quickly into the digital age, but the broadcasting and electronics industries are rushing to wrap up a million details of the transition.

So big and expensive is the undertaking that many public TV stations, as well as commercial ones, are likely to miss the FCC's deadlines to start simulcasting in digital in 2002 (commercial) and 2003 (public). The FCC already has compromised its transmission power requirements to make the deadlines easier to meet. The commission originally wanted to switch entirely to digital by 2006, but that, too, is unlikely.

Besides wanting to replace the 50-year-old analog technology that limits what TV can do, the government is counting on the conversion to free up some TV spectrum which it can then auction to cell phone companies, taking the proceeds to ease the federal budget pinch.

Planners say public broadcasters won't make the most of the switch to digital unless they get serious about digital asset management (DAM) and identify their digitized programs with computer-readable metadata. Technologist Steven Vedro provides a primer on DAM.


How did DTV come to be?

After long studies by industry committees, the FCC adopted a technical standard in December 1996, an expedited timetable, ground rules and a preliminary channel allocation plan in April 1997, and a final channel plan in February 1998.

Seven public TV stations were on the air by November 1998 and three more debuted in 1999.

Some already have been broadcasting experimentally for years. The first public DTV station — KCTS in Seattle — turned on its experimental transmitter in January 1997. Public stations formed a Digital Broadcasting Alliance to test and publicize the technology.

All public TV stations must have their digital transmitters going by May 2003. Under the FCC's timetable, the old analog channels will go off the air and be given back to the government for auctioning.

Broadcasters are not universally pleased with the digital technology chosen by the industry committee. Some engineers say the FCC's transmission modulation standard contend the DTV technical standard may deliver a useless signal to many would-be viewers using indoor antennas. Early in February 2000 the FCC turned down a petition to reopen the issue.

The table of channel allocations adopted in February 1998 was the FCC's third try. The first time around, in July 1996, the commission tried to squeeze 1,900 new channels and reduce the spectrum at the same time than television uses now. Public TV, like other broadcasters, urged the commission in November 1996 to use the full TV band and also took the opportunity to push for wider coverage areas for currently limited UHF stations.

Simulation of HDTV picture

How will public TV pay for the transition to DTV?

Public TV stations face DTV costs that could range from $2 million for a station that could do little more than transmit national programs to $6 million for a facility that could produce its own programs. The total costs estimated around $1.7 billion amounts to nearly the entire annual income for public TV plus public radio, which will have to be spent largely in four or five years.

By fall 1998, most public TV stations had only begun planning how they'll make the changeover. Many stations kicked off their fundraising by hosting stops on a national tour to demonstrate DTV to opinion leaders. Some stations got off to a fast start raising funds from state legislatures, and they had  mixed levels of successes with the states in 1999.

In Maine and then in North Carolina and New Mexico, voters approved bond issues that will pay for DTV conversion of stations in the states. (In North Carolina, where the bond money will be used to upgrade college facilties, and where the public TV network is licensed to the state university, some reporters clashed over conflict-of-interest issues with the university-owned state TV network. Later, UNC pubcasters responded to the controversy in letters to Current.)

A number of stations began building their equipment with piece-by-piece aid from the federal Public Telecommunications Facilities Program. But those sources aren't likely to cover the whole bill.

Fourteen public TV licensees (and many more commercial stations) may get unexpected help: They may have the option of giving up one of their duplicate channels earlier than expected and earning large sums from the cell phone industry. Late in 2001, the public broadcasters hadn't decided whether to take the offer.

By fall 2000, public TV had made substantial progress with state governments and private donors, but lost millions in federal conversion aid when Congress didn't or couldn't pass an authorization bill. A CPB authorization bill, which could have done the job, is already years overdue and may have been further delayed by 1999's list-swapping issue.

In 1997, CPB initially sought $771 million from the federal government to cover 45 percent of the estimated $1.7 billion transition costs, but the Clinton Administration backed $450 million, including $375 million in new money, and the field compromised on a $600 million request to Congress. In the first congressional hearing, House leaders reacted skeptically and felt to urgency to act.

Public TV's broadcast engineers closely monitored plans of electronics manufacturers so the new generation of equipment will fit pubcasters' needs.

In recent years, the government's decision to grant the extra channels for the DTV transition became intertwined with public TV's search for long-term operating funds to replace the shrinking federal appropriation to CPB. In 1995, when CPB funding was under sharp attack by Republican leaders, public broadcasters believed the digital spectrum was the only major federal resource that Congress would consider investing to subsidize public broadcasting. House telecommunications subcommittee Chairman Jack Fields backed the idea of a trust fund for public broadcasting, but was not willing to put much spectrum into it, and his bill went nowhere in 1996.

Then in 1996, Fields' successor, Chairman W.J. Tauzin, began floating the idea that commercial broadcasters pay a fee for their digital channels, part of which could help support public broadcasting. The FCC pledged the channels to broadcasters without any such quid pro quo, but in October 1997 President Clinton appointed an advisory committee--the so-called Gore Commission -- that may attempt to impose some new obligations on broadcasters in exchange for the channels. The committee discussed "pay or play" deals by which commercial broadcasters could play public-interest programs themselves or "pay" pubcasters to carry them, but by April 1998, it was searching for "win-win" solutions that commercial broadcasters could sign onto. Tauzin also kept alive the idea of a tradeoff that would require commercial broadcasters to help pay for public broadcasting.

How will DTV technology be used?

The FCC's initial reason for moving to Advanced Television (ATV), as it was called initially, was to let over-the-air broadcasters offer high-definition (HDTV), as cable systems, videodiscs and satellite broadcasters probably will do in coming years.

But as planners shifted ATV plans from analog to digital, they realized HDTV is only one of the uses that could coexist on digitally transmitted channels. By the time the FCC issued its rules in April 1997, it had decided to make HDTV entirely optional for broadcasters using the new DTV channels.

High-definition still presents the clearest advantages to most consumers. DTV sets will be able to display terrific wide-screen, high-definition pictures with 720 or 1080 scanning lines, compared to about 480 visible lines in the old NTSC analog standard, plus up to six channels of Dolby sound. PBS debuted its HDTV service in November 1998 with a visually bountiful documentary on Dale Chihuly's glassblowing tour. It was produced by Seattle's KCTS, which has been using HDTV for years to make a popular series of aerial travelogues, even though the full quality won't be seen by home viewers until they buy HDTV sets. Experienced HDTV producers urged TV producers to begin making programs suitable for future digital broadcast, at least conforming to the shape of DTV's 16:9 wide-screen picture, if not also providing high resolution. By 2004, technology had advanced and receiver prices fallen enough to convince a former skeptic, engineer Bruce Jacobs, that HD was looking like a good bet for public TV.

Enhanced or interactive DTV brings to TV the capabilities of web pages and interactive compact discs, permitting huge quanitities of text, sound, images and computer programs to be downloaded along with broadcasts. Though the interactive side of DTV developing more slowly than expected, public TV producers are still developing prototypes of the "enhancements" that will be broadcast along with PBS programs in the future. The network planned to join in field tests late in 2000. Viewers will be able to call up some enhancements during a broadcast and will have to wait until afterward to see others. In 2000, PBS and several producers began working with cable operators on viewer tests of web pages and other "walled garden" interactive data that resemble future DTV enhancements. PBS and Intel Corp. demonstrated one kind of enhancement with an interactive supplement to a 1998 bio of Frank Lloyd Wright. CPB began an ambitious R&D program called DTV 2K3 to develop prototypes of enhancements. To get practice with DTV's interactive capabilities when the standards and equipment for DTV aren't fully developed, producers at several public TV stations experimented with producing for Web TV Plus, a consumer product that combines Internet surfing with TV viewing. Producers developing prototypes can choose between making synchronous and asynchronous (post-broadcast) enhancements.

Multicasting will allow stations to air four or more standard-definition (SDTV) program streams at the same time, and/or various data and audio channels. Public TV stations generally expect to multicast during the day and do HDTV at night, but by 2002 some were planning to air HDTV and a separate standard-definition channel simultaneously. Among the options for filling the channels:

Until DTV audiences and services develop, Milwaukee's public TV station demonstrated multicasting by using a channel to follow a season in the life of an eagle family in northern Wisconsin.

Stations are using multicasting as a key selling point to get state aid to help cover digital conversion costs. In 1999, PBS announced PBS Kids and PBS You (adult education) channels for distribution through DBS as well as multicasting.

Education is likely to be the purpose of much of public TV's digital output. Three-quarters of stations said in a 2001 survey by APTS that they expect to carry at least two multicast services for formal education.

Revenue generation seems a likely by-product of the DTV transition for financially strapped stations. The FCC decided in fall 2001 to let public TV use "excess" capacity in its digital transmissions to make mone. The ruling won't permit commercials on broadcast channels, and pubcasters say they don't know what revenue-generating options will turn up as DTV develops. Public TV raised the possibility in a 1999 petition to the FCC. Various public-interest groups intervened to oppose paid advertising. That same year, a venture capitalist told station executives that the stations' DTV channels are "very valuable real estate."

It's still not clear exactly how fine the high-def pictures should be, since few consumers will have really large screens in the near future. Microsoft Corp. and other computer interests successfully lobbied in 1996 to prevent the FCC from formally endorsing the 1080-interlaced format, which is the highest-HDTV among the 18 formats within the proposed Grand Alliance standard. Even two years later, Microsoft continued urging broadcasters not to use the interlaced format, which is incompatible with present-day personal computers. Some technicians, including Bruce Jacobs, past chairman of the PBS Engineering Committee, say 1080i is so good that few people will be able to see its quality in real-life viewing, while it uses so much transmission capacity that it forecloses the benefits of multiple channels.

In the public opinion vacuum, the various factions of the communications industry have been divided in their thinking about how to use DTV -- for a single HDTV picture or multiple SDTV pictures, or some combination of the above. PBS and some public TV stations, and commercial broadcasters like CBS's Joseph Flaherty, have been eager to lead the HDTV transition, while others would rather air several SDTV channels. In 1994, some commercial broadcasters began pushing the government to be given "flexibility" in how they could use the new ATV transition channels. Public TV supported the idea as an interim measure, to expand educational services until HDTV is well established. But the commercial broadcasters' willingness to put HDTV on the back burner while they pursued multiple SDTV channels made them vulnerable to charges of profiteering, which came from both the right and left wings.

Though public TV had little money to put into the development of DTV, PBS engineers were active in industry groups that tested the DTV standard. Competing standards were tested competitively at the Advanced Television Test Center, next door to PBS headquarters in Alexandria, Va., and then most of the competing companies joined forces to create the "Grand Alliance" standard. The companies were AT&T, General Instruments, Massachusetts Institute of Technology, Philips Consumer Electronic, David Sarnoff Research Center, Thomson Consumer Electronics and Zenith Electronics. As the proposed standard was completed in 1995, PBS worked with commercial broadcasters to keep open the broadcasting industry's laboratory where the standard was tested.

What about radio's transition to digital?

Radio is also facing a digital transition, which may be much less expensive and simpler for stations. It will be more like television's transition to color broadcasting, with both the new and the old signals simulcasting over the same channel -- "in band, on channel" (IBOC). In November 2001, an industry group, the National Radio Systems Committee, asked the FCC to create a standard.

The proposed IBOC standard combined technologies from two firms that tested systems in 1999.


Outline links: DTV-related web sites

Major documents about DTV

FCC digital TV documents on the commission's web site

Advanced Television Systems Committee home page and text of standards

DTV channel listings compliled by Doug Lung for

Digital Television Closed Captioning -- DTVCC Working Group

Sites about DTV and HDTV

HDTV Pub — market-by-market DTV reception reports and more, published by Andrew Reberry (also known as CheckHD), operated by the Consumer Electronics Association, helps consumers determine what DTV stations they could receive and where to point their antennas.

HDTV Newsletter — published by Dale Cripps

Digital Coast Daily

Digital Television Online — published by Broadcasting & Cable magazine


Digital Television and HDTV Talk — bulletin board

Interactive TV Today

How Digital Television Works by HowStuffWorks.Com

Television Technology — A Short History — on FCC site


International DTV sites

BBC's digital TV page

Broadcast Papers.Com — technical white papers

Canadian Digital Television

Digital Television Group — clearinghouse for terrestrial DTV in the United Kingdom

Digital Television —website of the U.K. government

Digital Television in Australia

DVB Project — the European Digital Video Broadcasting standard

Public broadcasting DTV links


PBS Online's digital TV site for viewers

PTV Stations: A List of Who Is Digital . . .

CPB's Digital TV site

ETV Cookbook, how-to resources about Enhanced TV, compiled by public TV's Local Enhancement Collaborative

"Digital TV: A Cringely Crash Course" on PBS Online

HDTV activities of KCTS, Seattle, public TV's leading producer of HDTV programs, and its Intris subsidiary

Digital TV pages on website of KCTS, Seattle, including its Digital Glossary

Iowa DTV Symposium, Iowa Public Television's annual national event about the digital transition

Organizations and manufacturers  in DTV



Cable Labs — the cable TV industry's technology development center in Colorado

Consumer Electronic Manufacturers Association DTV Summit and Market Overview on Video Products

Dielectric — transmitting antenna manufacturer

Dolby Laboratories —tech info on Dolby Digital sound used in HDTV

General Instruments Digital Network Systems product pages

Harris Corp. Broadcast Communications — major transmitter maker

Hi-Vision — site promoting Japan's original analog HDTV system from NHK

MIT — Research Laboratory of Electronics, Advanced Telecommunications and Signal Processing Group

MSN TV — Microsoft's transitional technology (formerly Web TV)

National Association of Broadcasters DTV issue papers, statements and releases

Sarnoff Corp. — formerly RCA Laboratories

Sony Pictures High Definition Center — Culver City, Calif.

Snell & Wilcox — British maker of image processing equipment

Thales — formerly Thomcast division of Thomson Electronics

Thomson Multimedia — including Philips broadcast systems

Zenith Electronics Corp. DTV pages

If you can suggest other useful DTV sites on the web, please send e-mail to Current.


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Web page revised Oct. 7, 2002
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