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DTV In The Real World

Mandated by the FCC, television stations have started to make the transition to digital television. But how did we get here? And how well is the industry responding to this revolutionary time? While the rest of this book will discuss technical issues associated with digital television, this chapter provides an historical context for DTV development and implementation, as well as observations about these early days of commercial DTV broadcasting. We begin our journey with the introduction from the first edition of this book, which provides a roadmap to DTV from the early days of broadcast.

From Yesterday To Today: A Perspective on the Digital Revolution

By Renville H. McMann, Jr.

I was born a little too late to see mechanical television over the air, but my family was lucky enough to have a 441-line, RCA-built, Westinghouse 12-inch mirror-viewed receiver in time for the opening of the 1939 World's Fair. This switch from mechanical disks to all electronic vacuum tube pickup and display was probably the first revolution in television history. Since then, revolutions have happened so fast and so often in TV broadcasting that there is a widespread belief, especially among non-engineering management, that the upcoming digital ATV transition is just another ho-hum change in the way of doing things. Those holding this belief are very, very wrong as a little history will show.

The first real revolution in broadcasting was the change from radio to television in 1939. Engineers, used to thinking of base bandwidths measured in kilohertz not TV's megahertz, generally had no knowledge of phase linearity, transient response, cathode ray tubes, gray scale, gamma, photo cathodes, etc. In fact, for the most part, they did not even have high frequency oscilloscopes to look at the TV waveforms they were trying to generate. Luckily for the industry, World War II trained thousands of engineers and technicians in the art of radar, the first cousin of television. Also, the total number of television stations was very small in 1945, building slowly over the next 10 years so there was time to learn the new art of television. Even so, lots of mistakes were made, and on some occasions some pretty terrible pictures were transmitted, but every year, little by little, the pictures got better. The Iconoscope gave way to the Image Orthicon, the Image Orthicon to the Vidicon, and the Vidicon to the Plumbicon, with these improvements occurring roughly over two decades.

Although each of these improvements was a revolution in its own way, each could easily be understood by engineers and technicians trained on the previous generation of technology. Ham radio was a good background and many a chief engineer got his start that way. For the most part, a few days' training by the manufacturer of the equipment was all that was necessary, along with a basic understanding of a circuit design, a little mathematics, and Ohm's law. We tend to forget that in those days equipment broke frequently, and the broadcast engineer was expected to quickly fix it himself and know how to work with a soldering iron and how to climb a tower to check out the antenna. Only in major breakdowns could he (there were very few shes in those days) get help from the manufacturer. At some stations, the chief engineer could not only fix the equipment, but he had actually built it in the first place.

The next two revolutions took place more or less simultaneously in the late 1950s, color and video tape recording. Color cameras could be considered as three black and white cameras operating in parallel and hence easily understood; the encoder and decoder did require going back to the books for a refresher on modulation theory, but the same skills honed over the previous 10 years were easily up to the task, and once again the engineers could easily fix it themselves. Video tape recording did require some new skills, mostly mechanical, and another refresher in modulation theory to understand the FM video. Tape recording, itself a revolution, spawned the TV production house, a new facet of our industry, and perhaps a revolution in its own right. However, for the first time the TV production house could not go it alone and build its own cameras and tape recorders, even if it wanted to, although some of the big networks did develop both on a limited basis. It was starting to be the age of specialists.

You will note that I haven't mentioned transistors as a revolution because, for the most part, transistors were just a new component, a small, low-voltage version of a valve, subject to the same design equations as the vacuum tubes before them. Transistors, while not a revolution themselves, did cause one: the advent of small, portable equipment which revolutionized station operations, especially ENG. Although small, this new equipment was very complex, and it caused a large-scale start of servicing by replacing boards, not individual components. TV engineers began to rely more and more on the manufacturer to fix things at the board level, and, as a result, had less understanding of the subtle intricacies of the equipment's design. Collections of transistors and integrated circuits came on the scene in the 1970s, and made possible high-speed analog- to-digital conversion, introducing the industry to digital picture manipulation, time-based correction, digital tape recording, electronic editing, etc.

Note that over 20 years later, this digital conversion of our plants is still not finished, and the equipment has grown so complex that sometimes the manufacturers themselves cannot understand or fix the designs they delivered only a few years previously. Just try and get a 1980 vintage frame synchronizer or noise reducer repaired if anything more involved than a power supply has failed. Thus in 20 years, we have passed from a completely analog plant to a partially digital one. The myriad problems encountered along the way were solved one by one as new pieces of equipment were introduced without jeopardizing the picture quality or interrupting the program flow. There was time for the manufacturers and users to experiment with the new gear in a non-crisis atmosphere, because the older versions were still around and could always be used as a backup.

Now comes digital television and ATV with its subsets of HDTV, SDTV, data transmission, program guides, etc. Not to mention video compression of 50:1 or more.

The FCC wants a complete conversion in nine years. This time, there is no time for an evolutionary approach. The job can be done, but it will require a massive effort on the part of manufacturers and users, both stations and production houses. Much of the needed equipment hasn't been designed, and in some critical areas, it hasn't even been invented. The old-time engineer is going to need lots of help from the new breed of software maven. Circuit design, while still important, needs to be supplemented by strong logic design and de-bugging skills. A mathematical background will be very handy when trying to decipher the discrete cosine transform or Trellis Coding. At first there will be problems, but none that can't be solved by the same type of person that can keep an Ethernet LAN up and running.

DTV: A Brief History

By Mark J. Pescatore

DTV has been in development for more than a decade. The FCC began its first inquiry into advanced television (ATV) services in 1987 at the request of 58 broadcast organizations, which jointly petitioned the Commission to explore the possible impact of ATV technologies on existing broadcast service. Later that year, the FCC established the Advisory Committee on Advanced Television Service (ACATS) to provide recommendations about ATV technical and economic issues. As discussion continued, all-digital ATV systems were developed, and ATV became DTV. In 1988, broadcasters and manufacturers funded the Advanced Television Test Center (ATTC) as a private, nonprofit organization to test new DTV technologies. Also that year, a group of cable television system operators established Cable Television Laboratories, Inc. (CableLabs) to work with the ATTC on the cable portions of DTV standards tests.

One important consideration throughout the evolution of DTV was that there would be no disruption of service to the public during the transition period. As a result, it was determined that broadcasters would be assigned a separate channel for their DTV signals. Once the DTV transition was complete, broadcasters would be required to surrender their NTSC frequencies. In fact, the spectrum containing NTSC frequencies is already set to be auctioned in 2002.

By February 1993, four competing digital systems were under consideration for (1996), the group developed a DTV system that would "...dramatically increase the tech adoption by the FCC, but none were recommended by the ACATS. A few months later, seven companies and institutions from the four DTV systems organized a cooperative effort called the "Grand Alliance." As detailed in the FCC Fourth Report and Order(1996), the group developed a DTV system that would "...dramatically increase the technical quality of broadcast television, helping to preserve for consumers and for our demo-cratic society the benefits of a vibrant and healthy free over-the-air television service in the future... [and] give consumers access to a host of potential information services..."

The Advanced Television Systems Committee (ATSC), formed by the Joint Committee on Inter-Society Coordination (JCIC) to create voluntary technical standards for DTV, considered which elements of the Grand Alliance's system would be voluntary and which would require FCC action. They also detailed five specific areas of the complete system: video, audio, transport, transmission, and receivers. The Advisory Committee recommended the standard to the FCC on November 28, 1995.

DTV Implementation

The FCC adopted a modified version of this standard as the DTV standard in the Fourth Report and Order on December 27, 1996. The FCC remarked that the ATSC DTV standard exceeded their expectations, and it would "provide a measure of certainty and confidence to manufacturers, broadcasters and consumers, thus helping assure a smooth implementation of digital broadcast television..."

On April 21, 1997, the FCC released the Fifth Report and Order, which outlined a number of service policies and rules for DTV. It included an aggressive eight-year strategy for the DTV transition (it was originally going to be phased in over a 15-year period), because the FCC felt that if DTV is not "available quickly, other digital services may achieve levels of penetration that could preclude the success of over-the-air, digital television." On November 1, 1998, 26 volunteer stations were scheduled to begin digital transmissions. By May 1, 1999, all stations in the top 10 markets affiliated with the major networks (ABC, CBS, Fox, and NBC) were required to be broadcasting a digital signal. Six months later, on November 1, all ABC, CBS, Fox, and NBC affiliates in the top 30 markets were required to have their digital signals on the air, though dozen of stations failed to meet their deadline and had to file for a six-month extension, with some filing for a second six-month extension.

All other commercial stations, including independent stations and UPN, WB, and Paxnet affiliates, have until May 1, 2002, to begin digital transmissions. All noncommercial stations will be required to have their digital signal on the air by May 1, 2003. The FCC has set a target date of 2006 for broadcasters to complete their transition to digital transmission and surrender their NTSC frequencies. This market-staggered approach was favored by most manufacturers and broadcasters according to comments received by the FCC.

In an effort to make sure the viewing habits of NTSC viewers are not disrupted during the transition, the FCC will begin a phased-in simulcast several years before NTSC is eliminated in 2006. By April 1, 2003, DTV stations will be required to simulcast at least 50 percent of the video programming from their NTSC analog channel. A 75 percent simulcast requirement will take effect on April 1, 2004. All analog programming will be required to be simulcast on April 1, 2005, a policy which will remain in effect until broadcasters surrender their NTSC analog channels. Note, the FCC can modify this schedule at any time and will review it in April 2001 and April 2003.

FCC Reactions

A few weeks before the November 1, 1998, volunteer start-up date, FCC Chairman William Kennard announced that 15 additional stations would join the original 26 volunteer stations in digitally broadcasting the October 29 space shuttle launch with astronaut John Glenn. Kennard said, "The fact that so many stations have committed to accelerating their DTV start-up...will be remembered as one of the most significant developments in the DTV transition process."

One year later, Kennard remained enthusiastic concerning DTV. "I am excited about the potential benefits digital television will provide to consumers," he said. "The build-out of digital television stations is proceeding at a fast pace, and is indicative that broadcasters understand the importance of getting up and running to compete in this digital era.

"It is heartening to see the increase of network broadcasts, including news, entertainment, and sports, that are being sent in digital format. This trend will only increase as more stations begin their DTV transmissions. As I have emphasized many times, additional content will be crucial to the immediate success of DTV."

FCC Commissioner Susan Ness was optimistic and realistic in her evaluation of DTV's commercial debut. "At the first year anniversary of digital television in the United States," she commented, "there is much to celebrate and much still to be done." Growing pains include tower construction (in some areas), copyright protection, cable carriage and compatibility, and receiver quality. Ness added, however, that consumer response to DTV has been positive.

November 1999: Momentum Is Building

By Mike Keller and Ross Kauffman

WCVB, the ABC affiliate in Boston, is the largest station owned by Hearst-Argyle Television Group and has served as a test site for all others in our group. Since we went on the air with a digital signal in October 1998, there have been many issues that we've had to deal with regarding equipment interfaces and specific gear that simply was not available in the beginning.

Basically, we've made all the mistakes here and paid the high prices for first-generation equipment so that the other stations in our group can benefit from our experience. We chose to be an early adopter station, even though our Harris transmitter was on the air before we had a single receiver in the market. In retrospect, we feel it was a good idea because our group had a number of stations that had to be up in May 1999. We didn't want to reinvent the wheel at every station. By getting a head start, we were able to recognize recurring DTV issues.

Including LMA agreements, we'll eventually install 29 digital transmitters within our group. As of November of 1999, the Hearst-Argyle group has five stations broadcasting in digital--WCVB, WTAE, in Pittsburgh; KCRA, in Sacramento, CA; KITV, in Hawaii; and WLWT, in Cincinnati, OH. Our goal as a station group is to have every station on the air and be capable of upconverting their NTSC programming to digital and passing through their respective network HD signals (when available) by the FCC's timetable. That's as far as we're going to go at this point.

The atmosphere in the early days of DTV was excellent, because stations were all trying to get a signal up and everyone seemed willing to lend their moral support. We were able to discuss different issues with other stations across the country that were doing exactly what we were. There were a lot of interface issues that caused us trouble initially, particularly the encoders.

One year later, the atmosphere surrounding DTV has become more competitive. At the station, we can easily view three stations with "rabbit ears" on our digital set-top receiver. With an outside antenna, we can pick up five! From a transmission standpoint, DTV has progressed at lightning speed.

We're also proud to say that we now have paid HD commercial advertising on our digital channel in Boston. This, I believe, is a direct result of an HD segment we produced in May 1999 for a popular show we produce (five days a week in NTSC) called Chronicle.

Showing the beautiful countryside of Vermont in HD (1080i HDCAM converted to 720p) made all the difference for us in getting the attention we were looking for from our audience. They knew the show in NTSC, so showing the improved high definition images allowed them to recognize the difference.

The HD episode of Chronicle has also allowed us to get involved with the NATPE/HDTV consortium of stations that shares HD programming. We acquired enough material from the consortium to host an "HDTV Week" in January 2000. We also broadcast ABC's Monday Night Football, which is carried by local sports bars, and that's been equally successful with the public.

Everyone who sees HD in our market loves it. Retail stores regularly sell out of the small amount of product they stock. We get feedback from a dozen or so active viewers in retail stores, research labs, and consumer homes. To quote an e-mail from one of our viewers: "I'll never watch football in 'narrowscreen' again."

By early 2000, we'll be averaging about 10 hours of HD programming per week. It's enough to keep people watching, but we still hear complaints that there's nothing to watch. We're trying to get more programming, but it has been a challenge.

The last six months has seen everyone--marketing, our general manager, and the public--taking notice, and we see a real momentum growing. Now that we've got someone willing to spend money for commercials, DTV has taken on a whole different perspective in our sales department.

Editor's Note: This essay originally appeared in a special section of Television Broadcast magazine commemorating the first year of commercial DTV service.


By Mark A. Thalhimer

Ask a broadcast engineer about the transition from analog to digital television and you're likely to hear about equipment upgrades, competing digital tape formats, disk-based video servers, television tower wind loads, digital signal distribution and the ongoing debate between 8-VSB and COFDM digital transmission technologies.

Ask a general manager about the same transition to digital and you'll hear about the unresolved digital must-carry question with local cable systems and the significant equipment expense in the switch to digital. He'll probably also bemoan audience fragmentation, the tense negotiations between corporate and the network about compensation and local avails, and the station's need to make the advertising budget next month.

Ask a news director about digital and you might hear about the need for a new news set because the old one shows too much wear in the crisp digital picture, or the need to frame the news anchors for both widescreen and standard format at the same time. You might hear some related talk about virtual sets and--if the news director is currently involved in talent negotiations--speculation about virtual anchors. The news director might also mention the need to upgrade the newsroom editorial systems--both the older script and wire editing system and the newer nonlinear video editing systems.


If all goes smoothly, the engineer, GM and news director will each play their appropriate roles in the new world of digital television. According to the generally accepted scenario, this transition to digital should replicate the shift decades ago from black and white to color television. It is supposed to follow a pre-approved course: Set a standard. Buy equipment. Begin broadcasting. And the audience, mesmerized by those beautiful pictures, rushes out to pick up a new DTV set. "Game highlights at eleven," is even more glorious and engaging in widescreen hi-def than it is today.

But something funny has happened on the way to the future. Namely, the Internet.

Some will ask what the Net has to do with a local television newscast. The answer is lots, and the answer can be summed up in one word: broadband. Fat, fast pipes into the American home. Those fat pipes are coming via cable modems, DSL telephone services and possibly the DTV signal itself. And those pipes won't just be going to a personal computer in the home office. They will also go to the digital television set and to the personal digital video recorder.

Integrated Digital Strategy

Stations should view their transition to digital television as a part of their overall broadband strategy, with the local newsroom playing a central role in this new digital world. The newsroom is the only way that a station can create and distribute high value content. News is the only content a station actually owns and that can carry a long-term brand. Local news often provides a significant amount of revenue for the station and is a significant editorial voice in local communities. Without the newsroom the station is just an antenna.

In this future scenario, the newsroom serves as the central information gathering space in the community. From that nexus the station is a "publisher" of information. In the morning, it publishes on television and perhaps also on radio, for those viewers who have left home and are driving to work. During the day, it publishes on the Web because busy people at work have access to PCs, not TVs. In the evening, it publishes on cable, over the air and even via satellite. And now the industry is starting to buzz again about "interactive television," which may provide yet another platform for the station: continuously updated local news and information available on-demand for the audience.

Analog Examples of the Digital Future

Much of this on-demand future is already beginning to happen. In almost 30, mostly major markets around the country, local 24-hour cable news channels have been set up to produce hyper-local news. These local news channels are priming the audience to expect news-on-demand, with an emphasis on local issues.

In New York, NY1 has a full-time subway reporter. In Washington, D.C., Newschannel 8 produces and broadcasts three separate newscasts (and associated regional advertising) for the three zones that comprise the nation's capital: the District of Columbia, Northern Virginia and suburban Maryland. This type of time-shifting or geographic zoning becomes very appealing if a local broadcaster decides to multicast the digital television signal.

Many broadcasters are already forming partnerships with other local media, like radio and newspapers, to share resources and increase the amount, availability and depth of local news. In Chicago, for example, CLTV "debriefs" numerous Chicago Tribune reporters each day to extend the reach of its local cable newscasts.

Extending the Broadcast

In Seattle, meanwhile, Microsoft's Web-TV is developing "Web enhanced" television newscasts with local television partners, as well as with NBC News and the News Hour with Jim Lehrer on PBS. In Silicon Valley, Internet startup companies like Yahoo Broadcast.com, FasTV, Zatso and a number of others are approaching local stations to begin streaming their newscasts onto the Net in anticipation of the broadband future. Today, it may be jerky, postage-stamp-sized video. In the future, it will be an on-demand newscast. Imagine the day when the audience can stack their own newscast. Or perhaps the technology will deliver something more like a personalized video clipping service. We just don't know.

Intel, the other west coast technology heavyweight, recently opened its Center for Datacasting Innovation, which will work with broadcasters to develop applications for data broadcasting on digital television. While just beginning, Intel describes its effort as focusing on the "tremendous opportunities that the convergence of Internet and broadcast technologies brings to the television industry."

On a more focused level, Silicon Valley start-up Geocast will soon unveil its turnkey system for local stations to datacast news, information, programming, advertising and e-commerce applications to personal computers. Geocast has announced partnerships with several major station group owners.

Not to be outdone, America Online is soon to unveil its entry into the interactive television marketplace. Calling it--what else--AOL-TV, the service is supposed to begin to bring together the best elements of the Web with the ease of television. AOL, don't forget, has a track record of simplifying technology for wide consumer acceptance where others have struggled.

Digital Refocuses the Picture

Where does all this lead? Is it high definition or standard definition? Is it widescreen? Is it multi-channel? Is it active or passive? Is it video or data? Does it need to complement my station's Internet strategy? What exactly does this "interactive television" thing that's being talked about include, anyway? Will we do a 24-hour local or regional channel? Will we time-shift local news programming? Will we try to geographically zone our newscast for different parts of our community?

These are just some of the questions local stations must answer in the next few years. Because, it's not just television anymore. It's digital television.


By Mark Bell

Digital newsgathering is 100 percent here.

Successful wireless communication is a miracle. However, once invented and used, making it more efficient is the challenge.

You can't speed up realtime acquisition of events. If the event is not carried live, however, it needs to be archived (at least temporarily), transmitted to an accessible point of storage, and processed for broadcast transmission or longer-term archive. Usually the last archive process includes compression of the material, as press conferences, long speeches, and a great amount of field material is not suited for archive or broadcast. Some call the process editing.

There may actually be a time in the future where it will be cost effective to have entire conferences and other long time events permanently archived, as digitized storage will be cost effective but intensive editing will not.

Today, we don't have to have any perception of information while it's in storage, unlike past days when film archives were kept in cans on special shelves. We have faith, perhaps more than ever before, that information will be just fine when it's retrieved, as it has been up to now in so many cases (and we're getting better at it). Many people are so absolutely sure information will be in their computers that they may become complacent and not so good at backing up their data as needed. Overconfidence? Yes. That's how dependable digital storage has become.

And that's what the future of news is about now. Acquisition of realtime events, multi-access storage, meta-tagged archiving so even the smallest visual gesture or single word can be retrieved. No degradation as with film and tape, and no cryptic scribbling on a label to try and decipher what's in the box or on the tape. It's just a matter of capacity, and capacity seems to be a product of time.

Storage capacity of systems has increased almost endlessly based on applications and operating speed, which have been built based on the availability of storage space. This phenomenon seems to be a perpetually upward-moving spiral. In the data storage intensive video industry, that's just fine, as hardware meets or exceeds what is needed, and is staying ahead of the ability of companies to keep up with technological changes and training.

At the time of the first edition of this book a few years ago, hard drives, as in the Avid CamCutter, were considered cutting-edge at a 1-1.5 gigabyte (Gb) capacity. Two of them fastened together in the CamCutter's disk pack would allow for about 20 minutes of record time and cost about $2,500. In contrast, a recent computer outlet newspaper ad offered 20 Gb hard drives for under $200. Logically, two 20 Gb hard drives working together with updated compression schemes would be far less expensive and hold almost 200 minutes, 10 times more data. That's a whole sporting event, with commercials, on two hard drives. It may also be a full day's news, documentary or commercial shoot. How long does it take for you to shoot 200 minutes of video? And remember, you can dump the bad takes as you go along; it's 200 good minutes.


A plain and simple Internet dial-up was used by this author to transmit material for the first edition of this book. Today, that same connection can be used for transmission of almost flawless full-motion broadcasts, but as with everything else, the workability is soon followed by improvements for practical applications. Many stations have made their material available through the Internet, and some Web sites offer their news stories for assembly into other newscasts. Free Web browsers and software are being used to view them, too. It seems as if more and more companies are coming out with modems that can transmit full motion broadcasts, and like acquisition, storage and retrieval devices, will keep getting faster and better in a very short time. The information demand and acquisition "dike" has been broken. Information flow is getting much easier.

Even the means of transmitting signals to a station have become faster and easier through digital. For long-distance signal movement, why not use the Internet? The use of high-speed lines, more and more of which are becoming available, will do just fine.

For shorter-distance wireless transmission, a new transmission scheme using Compressed Orthagonal Frequency Division Multiplex (COFDM) has been embraced by news broadcasters (see The How and Why of COFDM) Simply stated, it is the transmission of many packets of data through a myriad of carriers numbering in the hundreds, only a few handfuls of which need to be received for reception and reassembly of the signal. COFDM has been successfully demonstrated at NAB and many other places, including live ENG. Those who have tried it have witnessed abilities to transmit and receive as no other a/v signal has been in the past--including from a moving vehicle in one manufacturer's tests. COFDM is actually obstruction-friendly and given its digital nature, looks great (or has no signal at all), without multipath distortion, fading, or containing other distortions broadcasters have become used to in analog transmission.

Mix that with compression schemes which allow for fractioned-time transfer, such as the multiple speed transfer time offered in Sony's Betacam SX format, and users can send from places previously dark at a fraction of the transmission time. It's similar to a small computer whose processing time has been significantly reduced by a faster processor.

COFDM-equipped news vehicles can transmit signals using a much smaller directional or omnidirectional transmission assembly than the conventional directional antenna-topped mast. The vehicles using the technology at NAB used an antenna only a few feet high, and drove under canopies, through tunnels, around buildings and in traffic with very few unacceptable signal distortions. Using masts on ENG vehicles may not be necessary in the future if receive sites and signal strength are set up in certain ways, which provides a cost savings and added safety benefit.

COFDM transmission also requires less power to transmit a quality signal, as power doesn't make the signal better as it does with analog. COFDM also allows for fixed as well as mobile transfer of information, so crews could conceivably transmit one location's material while traveling to the next. This can be a real plus for that great friend of news, speed. With line-of-sight requirements eliminated, moving while transmitting is possible, and distortions such as reflections are eliminated, it rids remote telecasting of many challenges associated with analog.

Another aspect of the movement of data will affect ENG, too: wireless data transmission through cell phones or other wireless interfaces. Pictures and many other data packets are being transmitted through small wireless interfaces at the present time, and some computers even have built-in cameras allowing real-time video to those at the other end of the data stream. Proof of the viability of transmission interfaces usually is followed by marketization and then the improvement in the devices, and frankly, with the size of the processors in camera-equipped computers, there is no reason that there can't be a broadcast-quality camcorder with the computer inside capable of logging on and dumping its data via wired or wireless interfaces as needed.

Cell phone transmission and reception has improved and evolved into digital networks that offer cell phone use with active digital processing. Handheld units are also used as discrete network walkie-talkies, which may represent another means of discrete data transfer. As indicated above, once digital, many "fade" factors disappear and error correction appears. The question becomes how fast and how much can be placed on the circuit.

Earlier editions of this particular section of the book indicated that the future would contain wired interfaces, for ISDN line "nodes" throughout cities, so crews could feed data directly back to receive centers. With the extremely rapid advancements in wireless transmission, however, wire or fiber nodes will be more impractical as time goes on. More wireless development is going on as this is being written than at any other time on the planet, and wired nodes will probably never need to be built. As development of the need for wireless becomes more defined, or those with vision dream on, even more will be invented. For instance, laptop computer modems with wireless interfaces are very common, and the demand for them continues to increase.

The future of ENG will center around portability, wireless transmission sent from anywhere, computer processed, meta-tagged, archived, retrieved in an instant to be sent or simply inserted live as the situation warrants, to or from a moving vehicle, to or from a base station, or in a direct feed right to the viewer's home. The pendulum swings from hardware-rich potential awaiting applications to application-rich dreams awaiting hardware. That's news.

LPTV Struggles To Survive

By Mark J. Pescatore

While the transition to digital television has challenged broadcasters with a variety of technical and economic issues, no group of stations has felt the effects more than low power television (LPTV). Many LPTV stations provide their communities with local programming, covering events and issues that other broadcasters ignore. By the time the DTV transition is complete, however, hundreds of LPTV stations could be forced off the air. New legislation has provided some relief, but many LPTV stations still face a grim future.

LPTV in Perspective

Although LPTV stations have been around for almost 20 years, many people who do not have an LPTV station in their market are not familiar with the services these stations provide. In most cases, programming broadcast by an LPTV station is not provided in its market through any other broadcast outlet. According to the FCC, there were 2,190 LPTV stations as of July 1, 1999, licensed in the United States. Comparatively, the FCC also reported 4,915 low power UHF and VHF translators, 1,229 full-power UHF and VHF commercial stations, and 370 full-power UHF and VHF educational stations. Alaska has the most LPTV stations, 250, which are part of a statewide educational network. The other LPTV stations are operated by some 700 licensees in more than 700 towns and cities, with an estimated two-thirds of the stations serving rural communities.

Although LPTV does have its roots in translator services, and the two services have similar technical specifications and regulations, the two entities are defined differently by the FCC. According to the 1982 FCC Report and Recommendations in the Low Power Television Inquiry, television translators are low-powered broadcast stations that receive a broadcast signal on one channel and retransmit it on another channel to viewers in remote areas outside the signal's original broadcast area. In contrast, LPTV stations have the option of rebroadcasting syndicated programming or airing original programming. As their name implies, LPTV stations have set limits of signal strength that are significantly lower than full-power stations. While they are considered a "secondary service" (yielding at all times to interference issues with full-power stations), they enjoy relatively few programming regulations or requirements.


To protect the existing broadcast system in the United States, the FCC decided that an NTSC signal would be simulcast along with an HDTV signal for full-power stations during the DTV transition. Full-power broadcasters would then temporarily require a second 6 MHz channel for their DTV signals. As a result, individuals unable to afford new HDTV televisions could continue to enjoy television service.

These additional frequencies for full-power broadcasters are part of the problem LPTV stations are facing during the DTV transition. In an already crowded spectrum (in some areas of the country), full-power stations will require two channels until at least 2006. That means LPTV stations, as secondary services, may be removed to make room for the new DTV channels of existing full-power stations. Although Polar Broadcasting, Inc. challenged the FCC with regard to this course of action in 1994, the U.S. Court of Appeals District of Columbia Circuit upheld the FCC's decision.

Though the FCC recognized the potentially significant impact on LPTV in its Sixth Further Notice of Proposed Rule Making in 1996, it commented, "...we believe on balance that the benefits and innovations to be derived from these actions outweigh this impact." Further, the FCC determined it was necessary to maintain LPTV's secondary status, because limited spectrum space in major markets would require some LPTV displacement (either switching channels or ceasing operation) if full-power stations were to receive a second channel for DTV transmissions.

The FCC estimated that 55 to 65 percent of existing LPTV stations would be able to maintain operations, but even losing 20 percent (a conservative number based on these early FCC estimates), more than 400 LPTV stations across the country could conceivably be shut down. Keith Larson, who was part of the original LPTV task force and is now assistant bureau chief for engineering at the FCC Mass Media Bureau, said the FCC had no firm basis for estimating a final figure for lost LPTV stations. He confirmed there will be some disruption of LPTV service, but it will more likely be in urban areas where the LPTV audience has access to full-power stations and spectrum space is more crowded.

LPTV Legislative Lifelines

Thus, in the name of DTV progress, LPTV was faced with elimination in major markets. Despite appeals from LPTV broadcasters, the FCC maintained that secondary service LPTV stations would not be eligible for DTV licenses initially due to insufficient spectrum space. However, the Commission did note that LPTV stations were not necessarily excluded from converting to DTV; they simply would not be provided a second channel.

In an effort to keep as many LPTV stations on the air as possible, the FCC provided relief opportunities for displaced stations and loosened broadcasting restrictions. First, the FCC authorized LPTV stations to apply for a replacement channel without being subject to competing applications when it has been determined that the station will be displaced. Some interference rules were also relaxed for LPTV stations, including some restrictions on LPTV channel placement. The FCC also maintained a policy to limit initial DTV licenses to existing full-power broadcasters, which prevents new stations from entering a market and interfering with current LPTV stations. Finally, LPTV stations were provided a "power boost" for the first time, as new regulations allow no limit on transmitter output power, though stations are only permitted an effective radiated power (ERP) of 3,000 watts for a VHF station or 150,000 watts for a UHF station.

What many LPTV broadcasters really wanted, however, was the security of equal billing with full-power stations; in other words, they wanted primary status. According to Sherwin Grossman, president of the Community Broadcasters Association (CBA), if LPTV remained a secondary service, it would eventually cease to exist. Responding to DTV's imminent effect on LPTV broadcasters, on April 21, 1998, the CBA petitioned the FCC to establish Class A status and award it to certain LPTV stations (as well as translators) to prevent displacement. The proposal would provide LPTV stations "primary spectrum user status, within their principal service contours, against all later authorized full power and low power stations."

The CBA also built a number of conditions into its petition, so not all LPTV stations were eligible (which means not all LPTV stations would be protected from DTV displacement). LPTV stations that qualified for Class A status would only include stations that had essentially mirrored the minimum operating schedule of a full-power station for at least three months and had included at least three hours per week of local or specialized programming not available from other stations in the area. Under the proposed rules, Class A LPTV stations would be permitted to convert from analog to digital, as well as request a second channel for its digital signal, provided the station did not cause interference to other primary stations. Although it was not enacted, the Community Broadcasters Protection Act of 1998 was recommended unanimously by the Senate Commerce Committee in October 1998. The bill had been opposed by full-power broadcasters concerned with additional competition for advertising revenue.

The Community Broadcasters Protection Act of 1999 was introduced in the House of Representatives on February 2, 1999, with similar justifications and restrictions to the 1998 Senate report. The bill did not require the FCC to issue a second channel to LPTV stations for the DTV transition, but provisionally allowed the FCC to grant the additional licenses barring any interference issues. LPTV stations could also elect to convert to DTV on their current channels at the end of the DTV transition.

This time, LPTV broadcasters had reason to celebrate, as the Community Broadcasters Protection Act of 1999, part of the Intellectual Property and Communications Omnibus Reform Act of 1999, was signed into law on November 29, 1999 by President Bill Clinton (the same spending package also gave satellite providers permission to retransmit local television signals). In the law, Congress recognized both the programming services provided by these broadcasters, as well as the economic difficulties they faced (money lenders don't necessarily welcome secondary broadcasters with open arms). Now, the FCC must establish a Class A license for qualifying LPTV stations, subject to the same terms and renewal standards as full-power stations.

After a long political struggle, at least some LPTV stations will be granted primary status instead of elimination as a result of the DTV transition. Legislation is in place, but debate continues regarding LPTV's peculiar position. Granted, LPTV station operators were aware of their secondary status when they signed on, but no one could have reasonably predicted the overwhelming need for spectrum space during the DTV transition.

Should LPTV be punished because full-power broadcasters need additional spectrum space temporarily, and should only select stations be given primary status? Conversely, should full-power broadcasters have to compete with new Class A stations as a result of the new legislation? LPTV stations in rural areas are expected to be relatively untouched by DTV as compared to urban stations; does this imply that LPTV stations in urban areas have less importance because of their location? Should local programming and other programming options be withheld from viewers because they live in a certain geographic region? While industry opinions vary widely, these questions can only be answered definitively through the legislation of the federal government and the actions of the FCC.

Watching TV on an HDTV: The Good, the Bad and the Ugly

By Michael Silbergleid

As the editor of DigitalTelevision.com, I purchased an HDTV monitor in 1999 to get a front-row seat for the DTV transition. So far, my reaction is mixed. Although the monitor provides the potential for exceptional images, broadcasters and cable system operators need to recognize the new challenges of the technology.

I bought a 34-inch diagonal direct view flat 16:9 CRT monitor, primarily because it actually fit in my entertainment center with a half-inch to spare on each side. (Of course it took three of us to lift all 181 pounds of it into position, but it was worth the strain.) Inputs were the cable tuner via a VCR, DVD (s-video), computer (s-video), and a set-top box (component-Y/Pb/Pr).

The first images I saw happened to be a cable station with decent reception. I was amazed. Then I watched a standard definition DVD via a consumer s-video cable that was line doubled in the set. In a word, it was stunning. I had never seen pictures like this in a consumer environment, especially in my own living room. I invited a technologically curious friend to watch some DVDs, and he's just purchased an HDTV projection set. It is true: once you see HDTV you want it (even if it's only line doubled). That is, until you stumble onto a signal with poor reception.

On my cable system, SCI FI Channel routinely provides a clean image. When it airs a movie in letterbox, it is a sight to behold on my HDTV monitor, even if I am blowing up the picture to fit (more on a problem with this later). WNET, one of my local PBS member stations, looks just as good. But channels with impulse noise, herringbone patterns, and other signal degradations do not translate well to the line-doubled world of HDTV. In fact, doubling the lines also means doubling the problems--they become twice as bad.

Your best defense against delivering poor signal quality is a digital infrastructure. You need to be producing, storing and sending out the best signal possible. Monitor the cable system, and not just at your station. How does it look at home to average viewers? Ask your staff to critically look at your signal via cable when they are home. If something in the signal looks bothersome, imagine how it looks upconverted or line doubled on an HDTV. Communicate with the cable system. Let them know that you are checking on the quality of the signal that they are sending to your viewers. Work with them to evaluate what they send and receive (maybe that is the problem).

Consumer H/DTV is far from a perfect science. But with all things, it comes down to how picky you are. The biggest complaint after picture quality: the station/network logo bugs.

Where does your bug sit? Have you seen where it sits if someone is watching on an HDTV? If they stretch or otherwise justify the picture, your bug will just get wider. But what if they zoom in for full 16:9, losing the top and bottom of the screen image? What if they zoom to fill the screen when you are running a program in letterbox?

Every bug I have seen sits just inside the 16:9 area. When I zoom in to fill the screen, I only see the top third of the bug. It looks like "stuff" in the corner of my picture, not a station or network identification. SCI FI Channel's animated bug is the worst, as it literally looks like white ants (real bugs) crawling around the corner of my screen.

In The Specs But Not In The Stream

Watching real HDTV (or as real as a consumer monitor will allow) is more stunning than a line-doubled DVD. Using a set-top box hooked up to my local cable system, I was able to receive the 8-VSB signals of HBO and WCBS-DT.

First, there is a visible difference between a line-doubled DVD and 1080i HDTV, with HDTV being the clear winner. But there are some drawbacks to the system.

There are still parts of the ATSC specification that are not complete or that are not being implemented. Current 8-VSB receivers lack dual-stream audio capability even though manufacturers know that broadcasters are already allowed to use it. Broadcasters, of course, can't use dual-stream audio, because it might mean viewers would get no dialogue or no music and sound effects. Present receivers also lack conditional access, copy protection, data applications, and even, perhaps, cable-TV channel compatibility and the ability to display closed captions. Agreements were reached in February 2000 on technical standards for direct connection of digital TVs to cable systems and on-screen program guides. The ATSC data-broadcast specification is expected to be approved in April 2000.

Start thinking about how your viewers will be viewing your signal in the next few years. After all, many retailers reported heavy demand for HDTV monitors and sets during the 1999 holiday season. Viewers will be in a 16:9 DTV world sooner than we thought.

The DTV Consumer

By Michael Grotticelli

With the turn of a new century, consumer electronics manufacturers are excited about the potential of DTV. After being accused of stalling the rollout of affordable digital receivers, manufacturers are making a real effort to educate prospective DTV customers with in-store information and network TV advertising. In an attempt to jump-start DTV set sales, they're also lowering the price.

The number of "digital-ready" sets sold as of December 1999 was around 125,000 units, mostly without DTV receivers. In comparison, more than 40 million analog sets were sold in 1999. Several CE companies have stated that 2000 is the year when the one millionth DTV set will be sold. To reach their goal, prices will have to drop to about $2,000, various transmission issues will have to be solved, and more regularly scheduled programming will have to become available.

Initial product offerings from consumer electronics manufacturers for digital television in 1998 were big (40 to 60 inches), clumsy rear-projection boxes--employing the 16:9 aspect ratio--that did little to generate consumer interest. The latest generation of sets, somewhat smaller in size and less costly, look to change that, as was evidenced by a new line of digital sets in a variety of prices that were displayed at the Consumer Electronics Show in January 2000.

Also on the market are a wide range of PC-based TV tuner cards that are capable of displaying full HDTV resolutions on appropriate multiscan monitors. Indeed, multiscan monitors with TV tuners are being made even larger to accommodate progressive scan signals on sets that look like traditional TVs.

As more advanced digital scan conversion and other proprietary imaging techniques have been built into newer digital sets, image quality has noticeably improved, as has inherent audio features. Most live HDTV events are now produced in Dolby Digital AC-3 (5.1 channel) and these new sets (in conjunction with the appropriate home audio system) really enhance the sound experience.

Digital TVs now available generally fall into three main categories: integrated high definition sets that include a digital receiver and display; digital set-top boxes designed to work with HD and standard definition (SD) digital displays (and, in some cases, with current analog sets); and DTV-capable displays that, with the addition of a digital set-top box, offer a complete DTV system.

The market is also starting to see a new generation of direct-view CRT displays, from 27 to 40 inches, third-generation front- and rear projection CRT models, and LCD-based monitors that provide incredible pictures and Dolby Digital surround sound at a slightly reduced cost. There are even digital sets in the 4:3 aspect ratio at a much more affordable price. Since price is an issue with consumers, the economies of scale that have cut the cost of other consumer electronics devices will certainly apply to digital receivers as well.

Heretofore, strategies for DTV receivers in home theaters have seen companies offering a large-screen "digital ready" display and making available--at extra cost--a separate set-top box that decodes analog signals and displays them as digital. Audio has been offered via Dolby Pro Logic surround. The strategy is that these "upscale" consumers can watch big, beautiful analog pictures now, and later, when more programming becomes available, they can purchase a decoder box to watch digital signals at HDTV resolutions.

These decoder boxes will also prolong the life of current analog sets, as consumers will be able to buy and watch digital programming in analog on their NTSC set. The benefit of these boxes, besides addressing the legacy issue, is that they can also be outfitted with internal hard drives and special software, from companies like Microsoft, Wink Technologies, OpenTV, Replay TV, TiVo, and others, that enables a wide range of interactive capability, virtual VCR-like features, and "personal TV" services. Since the set-top is connected to the Internet, this software can be upgraded with or without the subscriber's knowledge, thereby eliminating obsolescence.

Although we've heard a lot of talk about the eventual convergence of the TV and the computer, companies looking to take advantage of these new interactive opportunities are being careful to create a comfortable "lean back" technology, not a "lean forward" one. As Microsoft founder Bill Gates said in his keynote address at the CES show, "People will continue to watch TV as they always have, they'll just have access to any number of separate devices via a home network."

The market is also beginning to see a new generation of DTV sets that feature built-in decoders that receive all ATSC formats and display them as a 1080-line, interlaced signal. The notion of a progressive scan receiver is certainly a viable alternative, as several companies have shown affordable, progressive-scan monitors.

Direct Broadcast Satellite (DBS) providers DirecTV and Echostar have also made arrangements with CE manufacturers to have satellite IRDs installed at the factory, so that consumers will have instant access to DBS services--including HDTV channels, interactive games, Internet access and E-commerce services. Thomson is one company that has led the way in this area, providing a built-in DirecTV decoder.

Several companies are offering flat-screen plasma displays that the average consumer may interpret to be a digital receiver, although these beautiful-looking models are currently analog receivers. Some companies have developed digital, 720-line, progressive-scan flat screens, but at this point are far too expensive to be considered a serious contender to the more traditional digital sets.

Additional advances have been made in the area of DTV set tuners that enable sets to lock onto and receive a specific digital channel. Most notably, a company called Microtune has developed MicroTuner, the world's first single-chip, silicon-based broadband tuner. The company managed to take what was once a cumbersome, steel component technology of the 1950's and place it onto a single chip that offers an integrated, universal solution for high-speed media delivery over digital cable, satellite and terrestrial transmission. It has been engineered with patented techniques to solve the packed-spectrum challenges of today's DTV landscape. Microchips like these will enable reliable reception on the smallest of devices, such as a watch or miniature Sony Watchman.

The one issue that has clouded the DTV reception picture is the use of 8-VSB modulation as part of the ATSC's DTV standard in the U.S. There have been some tests that have shown that the COFDM modulation system (used in Europe and elsewhere around the world) does a better job of distributing a terrestrial signal to indoor antennas. Although there are advantages to both modulation schemes, it has become clear that until this issue is solved--either with the newer generation of VSB reception chips or with COFDM--consumers will not be eager to buy a digital set if it won't work in their neighborhood.

Measuring Screen Size

We currently measure 4:3 TVs using a measure of the diagonal of the screen, but 16:9 TVs pose a problem in being able to compare image size when discussing the diagonal size of the screen. Typically, we may want to know how big of a 16:9 screen we need to match the height of a 4:3 screen (for the same height of screen, a 16:9 screen is 33 percent wider).

Above is the relationship of 4:3 screens to 16:9 screens and to 16:9 letterbox in a 4:3 raster, based on common screen height, as well as the three and six times viewing distance from the screen. (Fox Television uses a three picture height rule for 720-line work and a six picture height rule for 480-line work.)

Fox Chart

Connecting To The Future

The Consumer Electronics Association (CEA, formerly known as CEMA) had been proceeding with four technical solutions to link cable and other set-top boxes to DTV receivers. This issue has still not been decided and agreed on by the industry, although the 1394 ("FireWire") interface is favored by most parties involved. Once this standard is decided (which could be as early as Spring 2000, when FCC Chairman William Kennard has threatened to mandate specs), manufacturers will include a 1394 interface on most of the monitors they sell. Consumers who buy a DTV set in the future will be able to receive digital cable and use their DTV sets with other digital technologies, such as DBS, DVD players, digital VCRs and computers.

In February 2000, the National Cable Television Association (NCTA) and the CEA reached an agreement on two of four issues holding up cable reception over digital TVs: technical standards for direct connection of digital TVs to cable systems and on-screen program guides. Unresolved are disputes over licensing terms for copy protection technology and labeling of TV sets without two-way digital connections to other consumer devices. The Federal Communications Commission, which has been pressing both sides for months to resolve the DTV-cable compatibility dispute, praised the partial agreement but warned that it would still consider proposed rules for copy protection and labeling.

The biggest limiting factor to displaying true HDTV right now is the masking screens employed on CRT-based displays. These screens, that define a picture's color and sharpness but also limit the amount of light that is displayed, currently can only display about 700 to 800 lines of resolution. Thus, a person with a set that claims to display 1080 lines is not getting the full HDTV experience. This will change with time (and indeed is starting to) as technology improves and prices for components come down.

In the meantime, there's no doubting that when consumers see HDTV, they want it. They anticipate the day when their TV is more than just a TV; it will evolve into the center of a home network that's totally interconnected with the rest of the house. However, consumers also understand the costs involved and probably won't embrace DTV technology until it becomes affordable.

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