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1993 - HDTV - Getting It Started in America

International Symposium on Broadcasting Technology Beijing, China
by Dr. J. A. Flaherty FIEE - Senior Vice President - Technology CBS Inc. - September 6, 1993

HDTV - Getting It Started in America (1993)

First, it is important to realize that the HDTV situation in America is unlike that in any other part of the world. This difference in our HDTV development stems from America's underlying belief in growth through competition in a free and open marketplace with a minimum of government interference. The freedom to create, to innovate, to profit, and even to fail with such innovations has always been the underpinning of American business.

The U.S. strategy for the introduction of Advanced Television is based on the provision of a true high definition service, transmitted terrestrially to the home. This approach will preserve the uniquely American feature of localism in broadcasting.

To accomplish this the Federal Communications Commission or FCC, the U. S. Government agency that regulates broadcasting, chose to integrate HDTV into the same VHF and UHF spectrum that presently supports the standard NTSC television service. HDTV would be broadcast on the blank, or taboo, channels presently unused in those that spectrum.

Thus, in April of 1990, FCC Chairman Sikes had announced:

  • 11...the Commission's intent is to select a simulcast high definition television standard that is compatible with the current 6 MHz channelization plan but employing new design principles independent of NTSC technology. We do not envision . . . that the Commission would adopt an enhanced definition standard, if at all, prior to reaching a final decision on an HDTV standard."


In September of 1990, in its First Report and Order, the FCC decided:

  • "We do not find it useful to give further consideration to systems that use additional spectrum to "augment" an existing 6 MHz television channel to provide NTSC compatible service.
  • Consistent with our goal of ensuring excellence in ATV service, we intend to select a simulcast high definition television system.
  • A simulcast system also will be spectrum efficient and facilitate the implementation of advanced television service. Such a system will transmit the increased information of an HDTV signal in the same 6 MHz channel space used in the current television channel plan."


Thus, America would adopt an incompatible simulcast, full HDTV, terrestrial service! There would be no halfway measures taken in America!

The second FCC Notice

Based on the FCC plan, each of the existing television broadcasters will have the first option on one of the 1657 new simulcast HDTV channels. However, the application time for the license and the construction time to build the HDTV facility will be limited.
In its second Notice of Proposed Rule Making, in November 1991, the FCC defined the time schedule for the implementation of HDTV, and for the replacement of the NTSC service.

This second FCC Notice stated:

  • "In keeping with our goal of expediting delivery of advanced television service to the American public, we propose to limit the period of time during which existing broadcasters would have the right to apply for a particular HDTV channel. ... We note that preliminary information appears to indicate that a three-year application and a two-year construction period will permit broadcasters sufficient time to begin transmission in HDTV in the vast majority of cases.
  • We envision HDTV .. . will eventually replace existing NTSC. In order to make a smooth transition to this technology, we earlier decided to permit delivery of advanced television on a separate 6 MHz (simulcast) channel. In order to continue to promote spectrum efficiency, we intend to require broadcasters to "convert" entirely to HDTV — i.e., to surrender one 6 MHz frequency and broadcast only in HDTV once HDTV becomes the prevalent medium."


The two year construction period was subsequently increased to three years, thereby providing six years for the existing terrestrial broadcasters to start an HDTV service.

In its third Notice of Proposed Rule Making the FCC proposed to transition broadcasting to an all HDTV service, and to require broadcasters to surrender one of their two paired channels in 15 years from the date an HDTV standard is set or a final table of HDTV channel allotments is effective. At this time the NTSC service would be abandoned, but this schedule will be reviewed in 1998.

The third FCC Notice

In its latest Notice of Proposed Rule Making issued August 14, 1992 the FCC proposed four broad HDTV (channel) allotment objectives for the implementation of HDTV.

  • To accommodate all existing NTSC stations, e.g., provide a second channel for HDTV service . for all existing broadcasters;
  • To maximize the service areas of all HDTV stations to the extent possible, and ensure all HDTV stations have a minimum service area of at least 85-90 km (55 miles) from the station's transmitter;
  • To allot all HDTV channels in the UHF spectrum; and
  • To prefer HDTV allotments in situations where a choice must be made between providing greater service area for a new HDTV allotment or additional protection for an existing NTSC allotment."


HDTV broadcasting in America, then, will depend on the selection of the HDTV terrestrial transmission standard, the issuance of a table of channel allotments, the subsequent conversion of television stations to HDTV via the second simulcast channel, the proliferation of HDTV television sets, and the availability of HDTV programs.

The start of the HDTV conversion process depends on the HDTV standard recommendation of the FCC Advisory Committee on Advanced Television Service, the FCC selection of the HDTV terrestrial television transmission standard, and on the issuance of the FCC table of HDTV channel allotments.

Following these decisions, the growth of an HDTV broadcasting service depends on the widespread availability and cost of practical HDTV equipment, and this depends on the demand for professional HDTV equipment on the part of the stations.

Finally, such demand depends on the public's interest in HDTV, and, thus, on HDTV receiver penetration. HDTV receiver penetration depends, in turn, on the availability and cost of HDTV receivers and on the quantity of HDTV programs broadcast "over-the-air", on cable, DBS, and via "home video". Without HDTV programs, HDTV has no meaning and would likely be greeted with studied apathy by a disinterested public.

As to the selection of the terrestrial HDTV transmission standard, Fig. 1 shows that the laboratory testing and the testing reports on the five proponent systems were completed at the end of last year.

However, in November 1992, each of the system proponents identified a series of improvements for their systems, and requested the permission of the FCC Advisory Committee to implement the improvements. A Technical Sub-Group of the Advisory Committee's Special Panel, chaired by Dr. Dorros of Belcore and myself, reviewed the improvement proposals November 18, 1993, and approved those that it considered appropriate.

The Special Panel of the FCC Advisory Committee met the week of February 8th, this year, to consider the test results and the proposed system improvements with a view toward selecting a final HDTV system to recommend to the Advisory Committee.

None of the systems was judged

While all the systems produced HDTV pictures in a 6 MHz channel, none of the systems was judged to have performed sufficiently well to be selected as the single standard at that time. But, since the all-digital systems performed significantly better than the hybrid analog/digital Narrow Muse system, this system was dropped from further consideration. The Special Panel approved the improvements for the four all-digital systems, and recommended expeditious re-testing of the systems.

The parent FCC Advisory Committee met February 24, 1993 and approved the recommendations of the Special Panel. Re-testing of the improved systems was scheduled to start in May, 1993.

During this time, and in parallel with the re-test planning, the four proponents began to examine the possibility of combining their efforts into a single HDTV system proposal in what became to be known as the "Grand Alliance". Naturally, such a "Grand Alliance" system would require review, possible modification, and approval by the FCC Advisory Committee, after which the system would have to be built and tested. Thus, the re-test of improved systems or the development of a "Grand Alliance" system will cause a delay of a few months in the standard selection process.

Nevertheless, it is expected that the Advisory Committee will be able to recommend a single HDTV terrestrial television transmission system to the FCC yet this year, and the FCC could choose a standard and issue a table of channel allotments during 1994.

After the FCC decision has been made, the growth of HDTV in the consumer market, will, as noted before, depend on the availability and cost of HDTV receivers and on the quantity of HDTV programs.

Programs! programs! programs! That is what it is all about! People watch programs, not technology!

As shown in Fig. 2, when color television came to the United States in 1955, color receiver prices were high and penetration was low. During the next several years the price of receivers declined by more than 50%, yet, with only NBC offering a regular color program service, the color receiver penetration did not increase significantly. It was only in 1965, when all three commercial television networks began broadcasting their primetime evening programs in color, that receiver penetration began to increase dramatically.

One can expect the HDTV conversion to follow a similar pattern as shown in Fig. 3. Here too, multiple HDTV programs must be available to drive HDTV receiver sales. This time, receiver penetration, as projected by the FCC Advisory Committee, Working Party on "Economic Factors and Market Penetration", is seen to increase earlier than that during the color conversion. The upper penetration curve is the optimistic projection, while the lower curve represents the mean of several conditions studied.

The earlier penetration estimates are related, among other things, to the regulatory encouragement for stations to implement HDTV, and to the fact that, unlike the color era, there are more distribution media in America today than just three national television networks. This time, cable systems, DBS, and "Home Video" plus PBS and Fox will be able to deliver HDTV programs to the home.

Completely different from Europa and Japan

As to the HDTV programs themselves, the HDTV program production situation is completely different here from that in Europe or Japan. Primetime evening television programs on the three commercial television networks have been produced in high definition for thirty years. Indeed, up to 70% of all primetime programs have been, and are, produced in high definition -- namely 35mm film.

This is a unique American experience. In most of the world 35mm film means cinema. In the United States it largely means television. There is nearly ten times more 35mm film production for television than there is for the cinema in America.

Today, in Hollywood, there are approximately 800 hours of 35mm cinema production per year, but over 8,000 hours of 35mm production for television.
The machine that drives this production effort is huge. The 8,000 hours of television programming that Hollywood produces annually for broadcasting, cable, and home video, requires 36,000 production days, and occupies more than 200 stages.

Thus, programs can be shot in wide screen on the same film using the same cameras used today to shoot normal television programs, and a large proportion of primetime evening programs in America could be broadcast in HDTV without an initial investment in electronic high definition studio equipment.

This base of HDTV programming would likely be sufficient to drive HDTV receiver penetration.

The problem in the United States will not be that of an initial supply of national HDTV programs. The problem will be that of converting the 1657 terrestrial television stations to HDTV on a practical, cost effective basis.

How and when can this be done?

Just three years ago, cost estimates, based on then available HDTV equipment or on projections of yet-to-be-designed HDTV equipment, led to station conversion costs of up to $11.6 million with initial "start-up" costs of $4.3 million.

"Start-up" facilities are the basic equipment and systems needed to start an HDTV service at a minimal level, sufficient to meet regulatory requirements and to:

  • Pass through a network HDTV signal;
  • Up-convert 525 line programs, promos, and commercials to the HDTV signal format;
  • Playback non-network HDTV programming; and
  • Record HDTV programming for delayed playback.

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1.3 million dollars for e simple HDTV studio

The biggest single cost, and the one a station must make first, is the cost of the simulcast transmitter, transmission line, antenna, and the minimal start-up studio equipment.

As shown in Fig. 4, the FCC Advisory Committee's Systems Subcommittee, Working Party on "Economic Assessment", now estimates that the cost of the initial "start-up" HDTV station would be in the range of $1.3 million for a "minimal" facility, to $2.2 million for a larger "transitional" studio facility.

In making this analysis, the Working Party had to make a number of assumptions, especially concerning the cost of the transmitter and antenna systems, which can vary widely with local conditions and requirements.

The major assumptions were:

  • 1. No new tower - only some reinforcement.
  • 2. No back-up transmitter.
  • 3. No back-up studio equipment.
  • 4. Antenna at 1,200 feet above average terrain.
  • 5. An antenna gain of 16.
  • 6. A peak transmitter power of 50 kilowatts.


Fig. 5 shows a simplified block diagram of this "start-up" HDTV simulcast station which receives, processes, and transmits incoming HDTV programs; records and plays HDTV programs and commercials on digitally compressed video tape; and upconverts 525 line programs, commercials, etc. to the HDTV signal format for transmission in HDTV.

Fig. 6 shows the cost of the "start-up" HDTV station to be $1.3 million.

While such conversion costs are certainly not insignificant, they are far less than those being estimated a few years ago, and it is expected that the costs will continue to decline as actual equipment is designed and manufactured and, when competition for the professional HDTV market intensifies.

Additionally, these costs here and in America cannot be seen as only HDTV costs. For a broadcaster to move into the "digital domain" even for normal 525 or 625 line television to take advantage of digital picture and sound quality, digital compression for multi-channel transmission, and the other digital facilities so often discussed, a station would have to be equipped with virtually the same simulcast transmitter, transmission line, antenna, and similar digital studio facilities as those required for HDTV.

Thus, the initial HDTV "start-up" investment is nearly the same as that to transition to standard 525 or 625 line digital transmission.

Fig. 7 shows a simplified block diagram of such a digital 525 or 625 line station with equivalent facilities to the minimal HDTV station. The cost differential between the 525 or 625 line digital facilities and HDTV facilities is approximately $260 thousand.

In short, the initial transmitter, transmission line, and antenna costs should be seen as digital costs - not just HDTV costs.
Virtually  all  communications  media  are  already  digital telecommunications, telephone, FAX, computers, etc.
Recorded audio is already digital via the compact disc.

All professional television production, post production, special effects, and video tape equipment is already available in digital form; and cameras, switching equipment, and ENG equipment, are rapidly becoming digital devices.

Home receivers and home VCR's will be digital devices within five years.

DBS systems in America will be launched as a digital services to take advantage of digital compression techniques to multiply their channel count. Cable Laboratories in America has completed its digital compression design and larger cable systems such as TCI are already converting to digital transmission at the subscriber level to increase their channel count. Thus, both of these distribution media have an important economic incentive to become digital delivery systems. They are not merely embracing a new and interesting technology for its own sake.

Fiber based television distribution systems are, by their very nature, digital systems able to deliver multi-channel high quality audio and video programs to a cable-like subscriber base.

Digital compression techniques can be used on cable, fiber, and DBS to deliver up to 10 independent 525 or 625 line programs or up to 2 HDTV programs per channel, all with high quality digital stereo and multi-channel sound.

Terrestrial broadcasting cannot transition from its soon-to-be-obsolete analog service to a competitive all-digital service without a second "transition" channel!

That second channel is the HDTV channel, and indeed HDTV will be an all-digital service. Thus, when the public moves to wide screen HDTV, the terrestrial broadcaster will be able to compete in this "new" television service.

At the same time, the terrestrial television broadcaster will also be able to compete in the standard 525 or 625 line TV market with digital transmission and/or with digitally compressed multi-channel TV.

In fact, as HDTV develops, broadcasters could transmit HDTV in some day parts, such as primetime, and multi-channel 525 line digital television in other day parts.

In short, the second digital HDTV channel is the key to terrestrial broadcasting's future!

Digital transmission and HDTV simultaneously

Digital transmission and HDTV have occurred virtually simultaneously and have been linked together in the minds of many broadcasters, but, in fact, they are two separate developments with different implications for terrestrial broadcasting.

The digital era is sweeping across broadcasting worldwide. The analog era is finished. No further significant development effort will be applied to analog equipment. Broadcasters who continue to pursue analog technology, or, worse yet, who start new services with analog technology will live to regret it.

Terrestrial broadcasting, satellite broadcasting, cable services, and "home video" must meet the challenge and adopt the digital developments, or become analog islands in an all digital sea.

At ISBT '91, I said:

"Today this new and revolutionary technology stands before us and before this symposium. As we evaluate the on-rush of this new television, and plan for its implementation, we must bear in mind that today's * Standard of Service' enjoyed by the viewer will not be his xLevel of Expectation' tomorrow. xGood Enough' is no longer xPerfect' and will become wholly unsatisfactory.

Quality is a moving target, and our judgements as to the future must not be based on today's performance, nor on minor improvements thereto. There is neither time nor money to embrace every minor improvement in broadcasting technology.

HDTV is a major change, and must be seen as such!

Multi-step schemes * sneaking up' on HDTV as a final goal, waste time and money, and do a great disservice to the viewing public who must buy several versions of receiving equipment and struggle through years of *evolution' on the way to real HDTV."

In the intervening two years, a funny thing happened on the way to 'evolution'. The reality of my observations overwhelmed "evolutionary" analog projects throughout the World, and new all-digital advanced television systems are rapidly sweeping away the old proposals. This, notwithstanding the mountains of money that were poured into these behemoths.

Thus, as we go forward together into this new television landscape, let us all put aside the past and look to the future, for as has been said in 1831 by Samual Taylor Coleridge:

"If men could learn from history, what lessons it might teach us! But, passion and politics blind our eyes, and the light which experience gives is a lantern on the stern, which only shines on the waves behind us".

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