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Tech Notes

Published by: Larry Bloomfield & Jim Mendrala

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March 20, 2000

Tech Note - 052


Talent does what it can, but genius does what it must!

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Subj: Further Adventures in 8VSB Land

By: Larry Bloomfield

(Ed Note:  Portions of the following appeared in the Broadcast Engineering, March 2000 issue, under Beyond the Headlines.  An expanded version is printed here with the publisher's permission.)

Is it Over?

No doubt, by now, your are aware that on October 8, 1999, the Sinclair Broadcast Group (SBG) petitioned the Federal Communications Commission (FCC) for an Expedited Rulemaking, requesting that the Commission modify its rules to allow broadcasters to transmit Digital Television (DTV) signals using both Coded Orthogonal Frequency Division Multiplexing (COFDM) as a modulation system standard in addition to the current Eight levels of Vestigial Sideband (8VSB) standard. In an attempt to bring this matter to a close, the FCC summarily denied this petition on February 4, 2000, with a unanimous vote of 5 to 0.  But, is the matter going away that easily?   

The SBG's petition had signatures that represent nearly twenty percent of the current full power NTSC stations.  SBG was not alone in the petition-submitting department; Univision filed a petition of their own also last November, which basically echoed SBG's petition.  In addition to this, agencies within the Federal government, such as the Department of Defense (See Broadcast Engineering January 2000), have also asked the FCC to hold open public hearings on this issue. Others have conducted similar tests and came up with similar results.

Earlier in the same week the FCC denied the SBG petition, Mark Hyman, Vice President of Corporate Relations for SBG set up a demonstration for Congress in one of the hearing rooms in the US House of Representatives.  The purpose was to show them the 8VSB receivability problems. 

The demonstration consisted of said-by-side tests using two analog TV sets (a 9 inch Memorex AC/DC portable and a 2-inch Sony watchman) and the latest ATSC-6Mhz receiver, the RCA DTC-100.  The antenna used for the DTV set was an amplified device.  The tests revealed that only one out of five Washington, DC DTV stations could be received without having to reposition the antenna for each station, whereas all 14 NTSC stations came in fine.   The analog sets needed no antenna other than the rod and loop that came with each.   

If more than 6 or 7 people were in the House hearing room, the one DTV station that could be received went away.  Hyman said: "Even Ralph Justice of CEA paid us a visit.  He checked out every wire, connector, behind the curtains and under the tables to make sure we were not doing any smokes and mirrors routine.  He saw the problem, but would make no comment, leaving shaking his head."  

Although many detractors in this issue have accused the proponents of COFDM of attempting to delay or even sabotage DTV, I have never spoken to anyone, who, on or off the record, has ever even remotely hinted at wanting to delay the progress of the implementation of digital television.  The politics in this matter, on both sides, have all the ear-markings of a knockdown-drag out fight for a public office in Washington, DC.  

The primary issues purported by the proponents of COFDM say lies in the inability of 8VSB to replicate each stations current NTSC coverage area due to problems relating to reception.  Since the whole purpose of commercial television is to deliver as high a number of viewers to advertisers, then common sense says that anything less than current NTSC coverage would not be acceptable, irrespective of the reason.

The FCC said: "Numerous studies conducted to date support the conclusion that NTSC replication is attainable under the 8VSB standard," in their press release.  "The concerns raised in the Sinclair petition had done no more than to demonstrate a shortcoming of early DTV receiver implementation," and continued,  "Manufacturers are aware of problems cited by Sinclair and are aggressively taking steps to resolve multipath problems exhibited in some first-generation TV receivers."

The FCC Office of Engineering and Technology (OET) said that they have "analyzed the relative merits of the two standards, and concluded that the benefits of changing the DTV transmission standard to COFDM would not outweigh the costs of making such a revision."  In addition to this concern they said, "Allowing more than one standard could result in compatibility problems that could cause consumers and licensees to postpone purchasing DTV equipment and lead to significant delay in the implementation and provision of DTV services to the public."  Concluding their argument of delay saying: "Development of a COFDM standard would result in a multiyear effort, rather than the "unrealistic" 120 days suggested in the Sinclair petition."

Responding to the FCC dismissal of their petition, David D. Smith, President of Sinclair said: "Although the Commission dismissed our petition, we welcome their larger interest and intent to investigate all aspects of DTV and its fundamental failure to date. Further, we are hopeful that our continuing efforts to shed light on the relevant DTV issues affecting our industry can now be supported by the industry as a whole. We look forward to participating in this review which the Commission committed to begin within 30 days."

There is no secret that the ATSC, Consumer Electronics Association, et al. hard to bury the SBG petition, but living in earthquake land, has prepared me for aftershocks which can be equally as impressive as the initial quake.  

In a press release issued the same day of the FCC decision, the Consumer Electronics Association (CEA) President and CEO Gary Shapiro issued a "victory" statement:  "As the only organization to file a petition with the FCC calling upon the agency to dismiss Sinclair's proposal, we commend the commissioners for today's unanimous decision. With this ruling, DTV's future is clear and paved for success. The FCC has wisely provided broadcasters, manufacturers and consumers with the certainty they need to move forward with the transition to digital television.

"Today's ruling will allow television manufacturers, broadcasters and all others involved in the DTV transition to return our full attention to what matters most -- providing consumers with the full benefits of digital television.

"I hope this ruling will close the door on this issue. As demonstrated by more than ten years of laboratory and field tests, 8-VSB is clearly the best system for broadcasting digital television in the United States. And retailers report that consumers who are viewing over-the-air digital television love what they're seeing."

CEA had not better let their guard down, as this contentious issue may not be permanently laid to rest with the decision either. Remember, the FCC said that it "recognized the importance of the issues raised" and would seek further comment on the issue during its biennial review of the progress in DTV rollout.

Having no allegiances on either side of this issue, it is interesting to observe the way things have gone and wonder by whom, when and were the next move will take place.  Based on other information, one would be foolhardy to assume that this issue is over. 

Broadcast Engineering uses information from SCRI, a New York based firm, for its "Frame Grabs," from time-to-time.  Des Chaskelson, Director of Research at SCRI International said: "In our most recent annual survey (January 2000), sixty-four percent of the respondents stated that they were interested in going to COFDM."  Chaskelson said that broke down to 26.2% were somewhat interested, 18.7% were very interested and 18.7% were extremely interested in making the move to or going directly to COFDM.  "With over twenty-two percent of the full power television stations responding to this survey, it is certainly representative of the industry," Chaskelson concluded.

Should we have spoken up sooner?

Looking back to the early 1990s, NBC was involved in the primitive 500-carrier COFDM system, the precursor to the present day DVB-T system.  It would appear that NBC has never really put much stock in any of the claims made by proponents of the 8VSB methodology and decided to examine the reception issue for themselves.

Several associates who were once fellow employees at the Peacock factory (NBC) served to confirm this observation when they recently disclosed to me some rather interesting information.  It is my understanding that in a General Electric Corporate R&D report commissioned by NBC, GE's R&D folks were asked to compared ATSC and DVB-T. This "confidential" report indicated that the DVB-T/COFDM was the superior system.

From my information, NBC then conducted a series of tests, which went on for about three weeks, just after the first of this year.  These January field trials were designed to validate or refute the conclusions of that earlier report.  I have had bits and pieces of it read to me over the phone; it is devastating in its criticism of ATSC.  The test site was Philadelphia, PA, using the facilities of WCAU-DT (CH 67) that markets NBC O&O.  The tests were conducted with a true 6Mhz DVB-T UHF system.  The test station was operated at 150 kW ERP, using a 15Mbit/sec video signal so they could examine bit rates comparable to 720P performance.  The stream was multiplexed or "bit stuffed" with another 3Mbit/sec signal similar to what would be the case with a mobile DTV or datacasting service.

According to my sources the receiver used for testing 8VSB reception was an RCA DCT-100, a recently introduced DirecTV/ATSC receiver & HDTV decoder, widely regarded as the best 8VSB receiver currently available to the public.

NBC, along with their parent (GE) company's Research and Development folks conducted the hush-hush tests by themselves.  DVB loaned and installed the equipment, but was not around during the tests.   NBC/GE R&D did a straightforward A/B comparison with an identical ERP ATSC/8VSB DTV station.  At all test sites and using "all types of antennas," the test results were virtually identical to those of Sinclair, in particular at the very high ERP's by COFDM standards:  The COFDM out performed the 8VSB, hands down. 

It wouldn't seem reasonable that NBC would do all this testing only to keep a lid on it.  I could not get the PR folks at NBC to either confirm or deny a letter to the FCC, but they did let slip that the tests have taken place.  When NBC believes in something, they have a track record of getting their way.  Remember the CBS color wheel vs. the RCA all electronic NTSC color system?  

An NBC Vice President, Peter Smith, who works on the network's DTV projects, confirmed that NBC had run tests that compared COFDM with 8-VSB in Philadelphia.  Smith said: "We have complete confidence in Sinclair's test results."  When 8-VSB receivers could not pick up anything, they tried COFDM, and it worked fine at "most" sites. 

NBC said they tried multiple generation 8VSB receivers; even one with the advanced equalizer 8-VSB chip.  All were disappointing and were considered inadequate for urban reception.

Smith said that NBC was in the process of presenting their findings to the FCC at the same time the FCC decision on the Sinclair ruling was being issued.  The NBC test results were not know by the FCC in time to have any impact denial of the SBG petition.  Smith said that NBC was also in almost complete agreement with Sinclair as to what should be done about the problems and NBC, without question, favors selecting a specific version of COFDM for use here in the US

Smith concluded by suggesting that NBC plans a next round of testing in Washington, DC, soon.

What is further interesting in this novella is that the NBC testing of DVB-T was known widely in the upper echelons of the DTV industry in Europe; dating back to the earlier GE R&D adventures. It is very impressing that the lid was kept so tight on this story until the last week of January.

Prior to the NBC revelations leaking out, the FCC were divided 2:2 on putting the petition out to comment with Kennard's casting vote for holding the course.  One cannot help but wonder if this move on the FCC's part isn't a tactical strike to suppress this issue before the NBC tests and the Congressional demos were publicized, but the FCC did leave an escape hole.  In their press release on the dismissal of the Sinclair petition they said: "…the issue of the adequacy of the DTV standard is more appropriately addressed in the context of its review of the entire DTV transition," promising that within 30 days, they (FCC) will commence its biennial review of the DTV transition and, as a part of that proceeding, will encourage parties to comment on concerns regarding the 8-VSB standard.

Other Broadcasters Did Tests?

Get engineers together, especially at a conference with a little libation, and the game of "One Upsmanship" will take on totally new dimensions.  Such was the case at the SMPTE conference in San Francisco in early February of this year.

Based on information disclosed in private conversations, more than one of the high-priced help from ABC let it slip that they too had been doing some receiver field tests and confided that ABC had reached similar conclusions in its internal studies.  If these ABC engineers have their way, there's no question that ABC will take its turn at bat. Can we now expect to see a split between ABC, NBC, possibly Fox, the independents and CBS et al on the modulation standards issue?

Most everyone who first got onto the 8VSB bandwagon has had some second thoughts.  My sources in Televisa, Mexico's leading network and affiliated with Univision here in the US, tell me that the preferred technical choice for DTV, south of the border, is now DVB-T and a political decision has been deferred, while they wait to see what we do here in the US.  Most other third party countries, which were considering ATSC, such as Brazil, have simply put these decisions into slow-motion while waiting for the plot to thicken here in the land of plenty.

(This story will be continued in Tech Note #523 to be out either later today or tomorrow)

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Subj:  SMPTE in San Francisco

By: Larry Bloomfield

On the first Thursday, Friday and Saturday of February 2000, San Francisco played host to the 34th Society of Motion Picture and Television Engineers' (SMPTE) Motion Imaging Conference at the swank Fairmont Hotel on Nob Hill.  Charles Hintz of California State University, Hayward, and Richard Mizer of Digital Diversified, Inc., chaired the program.  In attendance were senior technical representations from virtually every major motion picture and television enterprise in the western world.

The first day consisted of an all-day seminar, followed by two days of paper presentations.  The topics of the papers presented were in the areas of Bandwidth, Bitrate and Resolution. 

Those present were exposed to a aggregation of information that ranged everywhere from informative to nothing more than pure, unadulterated infomercials; all of which were given by a cadre of very bright and intelligent speakers ranging in quality from gifted to those who sounded like they were auditioning to be busy signals for the telephone company. 

There were several things that, even after a few days, left me, as both a member of SMPTE and an observer, uneasy.  I probably would not mention them, but déjà vu: others in attendance also expressed similar concerns.

I was embarrassed that high priced salesmen were permitted to hawk their company's wares instead of letting those present in on the technology that got the wiz-bang devices or technology to the marketplace in the first place.  Their talks amounted to nothing more than "Oh what a great, new, wonderful product we've got and it will save the world."   Admittedly, all were interesting, irrespective of the nature of the presentation. 

The second thing that was embarrassing was to see the several very gifted engineering types, who know their stuff, are prominent in the industry, stand up before their peers and display their inability's at being able to address an audience.  No one is asking for a network staff announcer, but I've heard 1Khz test tones that had more inflection than they did.  Perhaps someone else could have been chosen to give the same presentation that would have been easier on the audience and the ears.

From my vantage point, there was a preponderance of balding and or graying heads present.  Except for the excellent job done by the student-volunteers from Napa Valley College's Telecommunications Technology Class of 2000, who are members of SMPTE Student Chapter 11 in the San Francisco section, there was an amazing lack of youth in attendance.  No one is criticizing those who attended, but merely pointing out that there should have been more "grass roots" participation.         

Although the range of information covered both the Motion Picture and Television communities, there were a number of sessions that were of particular interest to broadcast engineers and the engineering staffs at transfer and post production houses.  It is not possible to address all the subjects or name all the presenters at the SMPTE San Francisco bash, but I will attempt to share with you some of the subjects that were covered.  The SMPTE staff announced that copies of the papers and proceedings would be available for interested parties.  

There isn't anyone who's been in the TV business for any length of time who hasn't had to deal with "chip charts."  An enlightening presentation was given on the different types of charts that have been used in both motion pictures and television and the advances that have been made in this area of the industry.  The anatomy, attributes and drawback of modern day test charts and the benefits of engineering test materials in the production environment and their current under use, was discussed.

A paper that included design considerations for HDTV lenses and explained the Modulation Transfer Function (MTF) considerations of the different types of lenses that are available was also a timely topic.  It was pointed out that the development of lenses for the HDTV market has been a long and arduous one.  Some of the techniques involved in putting an HDTV lens together were also covered.

It was announced that there are continuing developments in the area of better CCD cameras and the advantages of twenty-four-frame, progressive scan, and high definition production were also discussed.  It was mentioned that YUV would be replaced in the future in recording equipment with red, blue and green and more than one presented said that in the future, television technology will not only be able to replicate film quality, but will surpass it.  It was emphasized that the industry should not be satisfied with what is now called Electronic Cinema and should strive for much better quality.   

Issues of upconversion options in digital television were discussed and "QoS" or Quality of Service, a term that is being bandied around in digital television circles these days was address and explained in the light monitoring multi-program DTV and MPEG.  The factors surround HD encoding and the specification EIA-818 was addressed.  It was pointed out that the biggest problem in MPEG encoding is a noisy signal.  It seem that encoders see noise as additional video information and can work overtime for nothing. Along with encoding, the benefits and disadvantages of both constant bit rate and variable bit rate methodologies were discussed.

One company discussed a new universal ½-inch VTR Based on MPEG 422P@ML for Production Application and how it, the D-11 video recorder, would accommodate that company's legacy ½-inch formats.  This was followed by a discussion about digital image compression in the film chain.  This subject, like many others was considered timely in light of the fact that most network television shows are shot on film and then transferred to tape for air. 

One of the industry's VSB gurus spoke about Digital VSB Fundamentals and Applications.   It was interesting to hear a progress report on MPEG-4 for audio-visual and IP service applications.  It was mentioned that MPEG-4 will be able to do live non-broadcast strings with no prior downloading required.  The standards surrounding MPEG-4 have yet to be adopted, but work is in progress.  In this light,  it was interesting to hear of the implementation of worldwide uncompressed video networks.

One of the oldest tape companies in America discussed the new "Tape-less Tape" operation at the Fox Network center.  It was pointed out that it has been performing nearly flawlessly.  A logical follow up to this topic was the discussion on video server architectures and the HD still store challenge.

With the possibility of some of the stations making the transition to digital considering multicasting and the centralization of group operations, advanced M/E architectures for multi-program environments received a very warm reception. In the same vain, keeping the plant in time has always been an issue and presentation on digital plant synchronization served to inform those who will need to know these techniques in the not too distant future.

We've all heard of convergence.  It was driven home in a talk about DVD meeting the Internet.  More and more stations are looking to the Internet as a possible means of distribution.

The formation of the SMPTE Digital Cinema Task Force was discussed, DC28 - with subgroups addressing Mastering, Compression, CAS (Encryption) , Transport (delivery/storage), Audio, Theater Interface, Projection, and Management Information Systems.

The home stretch of the conference was dedicated to D-ILA, Home Cinema and Digital Cinema Projection.  The final presentation was a prelude to the closing evening event.  It was a discussion of the all-digital pipeline: Toy Story 2, from Pixar Animation Studios in Richmond, CA.  The finally was truly impressive.  It was also amazing that AMC theaters would give up one of their viewing rooms on a Saturday evening, in the heart of San Francisco, to let Disney, Pixar and Texas Instruments hold a private showing of Toy Story 2 for the SMPTE assemblage.  Pixar went into great detail about the QuBit recorder technology used with Toy Story 2.  The incredible part about the movie we saw was that at no time was the feature ever on film.  It was computer generated and displayed electronically, from start to finish. 

We are truly living in a very interesting time.  Technology is advancing so rapidly it is nearly impossible to stay abreast of it without a great deal of effort. Considering the fact that this is only the beginning and significant improvements in electronic cinema are just around the corner, it can only get better.  It will impact the broadcast industry as well.  We will have continuingly improving material to air in HD.

It was very interesting to listen to the questions and answers as each paper was presented.  The technical back and forth served to sharpen everyone information flow.  There were many similarities between these discussions, but it is not possible to talk about one part of digital video without it having an effect on most everything else.  One observer said it:  "It was a bunch of middle age men talking about the number of pixels per micro-mirror, giving rise to the memory of middle age theologians' and their heated talks about the number of that could fit on the head of a pin."  One could certainly take that tact when things are moving so fast it difficult to discern where, when and how the technology is going.   

The general tone of the conference was polite but objective skepticism was expressed over most current and proposed solutions.  There were definite calls for a system and standards that are clearly superior to film, not just comparable. Unfortunately, there seems to be an attitude in some circles that things are "good enough," then "progress" in this area might not wait for the traditional processes of standardization.

It was refreshing to see new players, like QualComm, unencumbered by legacy customers, have some very interesting proposals in the areas of image compression -- intra-frame variable block sized-DCT which, I believe, yields 2:1 efficiency improvements. 

It would not be fair to close this report without mentioning further the great job the folks from Napa Valley College rendered in helping with the audio/visual areas of the SMPTE conference, while being afforded the opportunity to hear about the latest technology.  This two-year college is a reservoir of talent that has a tradition of filling many of the entry-level position in the industry.

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(Ed Note: The Editors and Publishers of the Tech Notes wish to thank Des Chaskelson, Research Director of SCRI International for his generosity in posting the Tech Notes on the SCRI web site.

Subject: HDTV Marketplace Trends and Product Reports: 2000 - 2004

From: Des Chaskelson , Research Director, SCRI International

The HDTV Marketplace Trends and Product Reports are now available. Data for the reports was derived from extensive surveys of US television stations in January 2000. The Trends report contains over 100 pages of data and analysis. Each product report contains data on the percentage of stations purchasing HD and SD units, by year (2000 - 2004), plus total units (HD and SD) by year. Over 35 products are covered.  For table of contents see online at: &/or contact:

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The Tech Notes are published for broadcast professionals, and others, who are interested in DTV, HDTV, Electronic Cinema, etc., by Larry Bloomfield and Jim Mendrala. We can be reached by either e-mail or land lines (408) 778-3412, (661) 294-1049 or fax at (419) 710-1913 or (419) 793-8340. The Tech Notes are sent (BCC) directly only to those who have asked to be on the mailing list, however feel free to forward them, intact (including this message), to anyone who you think might be interested.  There is no charge for this Newsletter, no one gets paid (sigh), there is no advertising and we do not indorse any product or service(s). The ideas and opinions are those of the individual authors. We still administer everything manually. We don't use any "majordomo" automatic servers. News items, comments, observations, opinions, etc., are encouraged and always welcome. We publish when there is something to share. Material may be edited for brevity, but usually not. Tech Note articles may be reproduced in any form provided they are unaltered and credit is given to both Tech Notes and the originating authors, when named. If they are to be used by a publication that normally compensates their writers, please contact us first.