Tech-Notes

Published by: Larry Bloomfield & Jim Mendrala

E-mail = hdtvguy@garlic.com or J.Mendrala@ieee.org

http://www.Tech-Notes.net

August 24, 2000

Tech Note - 062

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Sharing experiences, knowledge, observations or anything relating to Digital Television, Digital Cinema, etc. with fellow engineers and readers is our purpose. Our mission statement, other relative information and this current issue of the Tech-Notes is now posted on our new website: http://www.Tech-Notes.net.  You can also find all our past issues there as well. We’ve had over 1400 visitors; Thanks.  We are growing.  We now have over 830 subscribers. Thanks to our regulars and welcome to the new folks.  This is YOUR forum! 

We need help, suggestions, etc. Visit us at: http://www.Tech-Notes.net.

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Subj: Hoaxes, viruses and the like
From: The U.S. Department of Energy

Check out this web site.  It’s worth the time.  It is also posted on our website.http://hoaxbusters.ciac.org/

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Subj:  We Just Might Have a Problem
By: Larry Bloomfield

“I believe, we must come up with a VSB system that is = COFDM otherwise COFDM will be the standard.  I don't understand why the urgency on this is not much greater.  It seems to me, unless this is taken care of the off-air DTV roll out will be delayed to a point that everyone will be on cable or a satellite”, said one of the members of the ATSC who asked not to be identified.  It is amazing just how bravoes these folks get if you promise to keep their anonymity. 

The number of households with/without cable responding to a question that was raised in one of ATSC’s Ad Hoc Group on Field Test Measurement and Methodology meetings reports that the current number of households (HH) receiving television is 100,800,000. 

The current number of HH connected to cable is 71,545,000.  The current number of HH connected to cable or an alternative provider (satellite, MMDS, etc) is 80,346,000. Further defining the 100,800,000 households, 34% have 2 TV sets. Of those 100,800,000 households, 40% have more than 3 TV sets. 

The report continued:  It is difficult to approximate how many TV sets in households served by cable, or others, are actually receiving over-the-air, since people do not always report additional sets tied to their cable system. However, it has been assumed that, in multiple set households, at least some of the sets are capable of over-the-air reception, whether or not they are also connected to cable. 

What is really interesting is not so much “the figures” above, but what followed them in the message.  It seems that the ATSC considers all of its deliberations and plotting to be on par with the national defense and should not be let public until the battle is all over.  No one is questioning the veracity of the individual members of these “teams” or Ad Hoc groups.  They are without question sincere, honest, upright citizens, but remember who they are serving and we’ve been led down that primrose DTV path, by them, before; and look where it has gotten us! 

It is quite one thing for a company or manufacturer, wanting to keep confidential or secret their “goings on,” but this should not hold true for any group that is setting “standards” that will affect every one involved in the television chain in the future.  These standards setting bodies should come up with they way things should be done, then let the companies and manufacturers go off in their cloistered laboratories and come up with all kinds of new and wonderful wiz-bang ways of implementing these standards.

When contacting the ATSC about this balderdash, nearly every level of staff and management at the ATSC stated that all their proceedings must be held in confidence; to the point of a non-disclosure agreement adhered to by all attendees.

When asked why?  I was told that the press would get things all distorted and wrong! (Like the ATSC never has.)  They went on to say the press was not welcomed to any of their deliberations; only engineers who have a stake in the business. 

One cannot help but ponder:  Just because we have always done something the same way for a long time doesn’t make it right or correct.  One member of the ATSC said:  “Reporting the raw events will not serve either history or the present debate.”  Since I have never claimed to be a reporter or journalist, my response to this is that of a fellow engineer:  Poppycock! 

Many important milestones in history have been lost to rumor, innuendo and other such kinds of inaccuracies as the result of this kind of thinking.  There are many reporters who would say that this treads on the right of the public, technical or not, to know what is going on.  This is not the planning for the invasion of Normandy.

By these persisting philosophies, there is little doubt that ATSC would not have permitted George Simon Ohm, a mathematician, into their meetings, as he was not a broadcast engineer.  The same would apply to Galvani, a biologist, and many others who have made significant contributions to electricity and electronics.  Only after a spirited PUBLIC debate, oriented to the setting of standards that affect “everyone,” can we rest assured that everyone’s best interests have been served and the agendas of various special interests have not been permitted to run ramped.  The history of the broadcast industry, electricity and electronics is fill with significant contributions by people for out side it’s “good-old-boy” folds. 

One would think that after the massive crises the transition to digital television is going through, ATSC and the rest of the alphabet soup in Washington, DC would welcome as much help, from as many sectors, as would have the temerity, after all that has happened to date, to step up and offer it!

When it appears to be the attitude of the ATSC that their rules are not meant to foil the public "interest, convenience, and necessity", or to reduce the 4th estate to rumor mongers.  I was told:  “All, or at least the majority of the companies, research laboratories, and consultants involved in ATSC, SMPTE, ITU, SCTE, AES, IEEE, and other standards setting activities respond to the commercial agenda's of their employers and patrons. They try to fairly present their needs, and negotiate in a semi-public manner technically acceptable solutions to the problems in our industry. Without this effort virtually none of the major advances in our business would have happened.” 

“It is only when companies negotiate in public that they feel there are clear risks, and the more public the more dangerous the risk. It is also clear that individual parties to the technical issues have work to do that does not, in most cases, include responding to the press,” were the concluding comments by the ATSC person to whom I was speaking.

It is refreshing to find that not all participants within the ATSC are of this attitude.  One can only respect and appreciate the honest open opinions of one like Frank Eory, a well know industry authority on  semiconductors being developed by Motorola in their efforts to address the problems being experienced in the real-life field test with 8-VSB.  Eroy fairly accurately sums up the feelings and tone of several members of the ATSC’s Ad Hoc Group (AHG) who are revisiting VSB’s performance.

“The urgency is indeed felt by various members of the VSB Performance AHG, who are now looking not only at future improvements possible “without” changing the standard, but also at 'backward compatible' changes to the standard that could potentially meet most of the requirements outlined in the Broadcaster's Requirements document,” Eroy stated.  The document Eroy is referring to is a list of requirement some broadcasters recently submitted to the ATSC after experiencing less than satisfactory performance in the field. 

Eroy continued:  “Let's assume that the Broadcaster's Requirements are taken as a given. In that case, I believe this is going to quickly boil down to a very short list of Key Questions:

1. Can 'backward compatible' changes *and* new demodulator/equalizer design approaches meet these requirements? Note that 'backward compatible' means that existing receivers are not adversely impacted. This is a tough one, because some potentially helpful changes may impact some receivers but not others. I don't know if that makes them 'semi-compatible' or 'incompatible' changes, but either way it's a problem.

2. If the answer to our first question is "yes," how long will it take for those new receivers to reach retail distribution?  Whether the answer to #1 is "yes" or "no," does the current commercially available COFDM standard (DVB-T) meet all the Broadcaster's Requirements? The upcoming MSTV/NAB tests could help answer this question, if they specifically seek to answer it. The key issues remaining to be resolved in answering this question are as follows:

3. Can DVB-T be implemented in the U.S. without changing the Table of Allocations?  A comparative test, which sets COFDM and 8-VSB average powers to the SAME level, will not necessarily answer this. The criterion for setting transmitter power levels should be "to meet the FCC mask", which will guarantee that the DVB-T emissions cause no more interference to adjacent channels than the 8-VSB emissions. This may or may not mean reducing the DVB-T transmitted power relative to 8-VSB. If, as some suggest, the issue of 'significant changes to the Table of Allocations if we go with DVB-T' is truly a "red herring," it would sure be nice if the MSTV/NAB tests could prove this once and for all.

4. Can DVB-T support VHF as well as UHF channels without significant compromises in performance? The answer may be "yes, but 2 separate tuners are required." It is unfortunate that there are no VHF DTV stations on air in the areas where MSTV is testing, but there are those who believe a single conversion VHF/UHF tuner could indeed support U.S. requirements in a DVB-T receiver. It would be ideal if MSTV could obtain DVB-T receivers that include such a tuner, to answer this question. Even if no VHF DVB-T tests are conducted, at least the presence of a VHF/UHF tuner in the receivers would indicate what if any degradation to UHF DVB-T reception is caused by the requirement for a dual band tuner. Unfortunately, all the European STBs are UHF-only.

5. The typical modification for 6 MHz operation is simple: change the SAW filter from 8-MHz to 6 MHz and change the crystal oscillator to the required lower clock frequency for 6 MHz. These customized "6 MHz DVB-T STBs" have not so far addressed the VHF issue.

6. What are the effects of impulse noise on DVB-T at U.S. transmitter power levels?  Some have suggested that this would not be as much of a problem for U.S. DVB-T as it is for the U.K., where the transmitter ERPs are much lower. To completely answer this question, some VHF testing should really be done. But at least some good data could be gathered at UHF in severe impulse noise environments (under power lines, indoor reception with an electric drill in the room, etc.)

7. Assuming the answers to both #1 and #3 are both "yes," the issue will come down to 2 -- TIME. The highest priority broadcaster requirement is "get this over with quickly." This is not just a broadcaster requirement, but also a strong desire of all of us -- to quickly get the DTV transition moving forward. The time required making new chips, new STBs, etc. to implement #1 may be significantly longer than the time to implement #3 for the U.S. market. It is a given that any 'improvements' to VSB that are not yet even defined will not be on the market for at least 18 months. If we find that 8-VSB can be modified to meet the broadcaster's requirements, but it will take longer than simply switching to DVB-T, is this a trade-off that broadcasters, the Consumer Electronics (CE) industry, ATSC, FCC, etc. are willing to make?

“Given the urgency and seriousness of the crisis in which we find ourselves today, the answer from many of you will be NO. I'm sure all of us would like to hear some feedback on this issue of TIME and DELAY. It is frustrating to many of us in the CE and chip industries that these requirements were not defined years ago. It is no doubt even more frustrating to those who pushed for "flexibility" in the transmission standard way back when, which would most likely have avoided this entire controversy. But the question now before us is "even IF the current transmission standard can be modified to meet new requirements, is it even worth doing? Is there or is there not another transmission standard already commercially available which could meet those requirements much more quickly?" Some of you will jump up and say "YES! DVB-T!!!" But the questions raised in #3 above need to be answered before there will be any serious consideration of this option.

“The other aspect of this is perception, as in "first impressions." Even if VSB can be improved to equal COFDM in multipath, made flexible in data rate vs. robustness trade-offs, etc., there is still the issue of the 'black eye.' Given all the water that has passed under this bridge, how will broadcasters, retailers, consumers, etc. react to "new and improved VSB?" With skepticism?  Probably. If, as many argue, the DTV transition is hopelessly stalled, then "something completely different" has merit in its own right, just by being different.”

Until recently it was not difficult to believe that ATSC stood for “Annihilate Terrestrial Service Completely.” That may not be their charter, but you sure could fool a lot of folks out there who’ve spend tons of money trying to make what they gave them work!  Perhaps with input from folks like Eroy, that is some ray of hope, yet.

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Subj:  The FCC’s Biennial Review of DTV
By:  Larry Bloomfield

The newswires have been ablaze with comments filed as part of the FCC's biennial review of digital television.  Topping the list was the Disney/NBC reply comments, which virtually had every news organization even remotely covering this event, to comment on their comments.  Even National Public Radio carried the story.  Headlines like: "ABC joins 8 VSB critics," were to be found nearly everywhere.  The story goes well be on the filings.  Needless to say, this has stirred the home fires at the Sinclair Broadcast Group, who have been spare-heading the drive to get an alternative form of modulation to 8-VSB, accepted. 

The key issues seem to be portability and indoor reception.  It is this latter issue that inspired Nat Ostroff, SBG's Vice-president of New Technology, to say, just prior to the congressional hearings on this matter: "If they can show it inside the House hearing room, we will congratulate them on having solved the problem." 

Probably one of the most interesting of the comments was a “one-liner” filed by iBlast:  "iBlast Networks, Inc., which previously filed comments dated May 17, 2000 in the above referenced proceeding, hereby withdraws those comments and requests that they be deleted from the record in this rulemaking docket."  The May 17 comments referred to were in support of 8-VSB. 

When questioned about this move, iBlast’s Vice-president of Broadcast Engineering, Peter Ludé said: "iBlast has been conducting a great deal of testing of 8-VSB indoor reception over the past six months, as part of our data broadcasting network roll-out.  Our observations of real-life conditions (as well as a peek at new technologies from the labs) have made us very optimistic about delivering broadband content using the existing DTV standard.  We can't wait to start!

"So why the retraction of our FCC filing?  iBlast is owned by some of the nation's leading broadcast group owners.  Upon reflection, we realized that our voice must be harmonized with those of our partners. Rather then filing independently, we withdrew our statement in order to speak through the iBlast-founding partners, who are fully backing the MSTV efforts to analytically assess the defacto standard.  We respect the disciplined process of MSTV, and along with the iBlast founding partners, will wait for their findings."

Probably one of the other comments of note, of the many filed to date came from WaveXpress: "In the debate over the modulation schemes (8VSB vs. COFDM) for the DTV standard, we stand agnostic, as our service is not technically dependent on modulation.  However, in order to have a successful service (application) it is important that the audience reach not be reduced by the need for large, directional antennas or special mounting, through poor signal quality in densely populated urban areas, or by limited acceptability in important growing markets (e.g. portable applications).  Any standard that compromises ease of use or places limits on the range of applications also places limits on the size of the addressable market.  Naturally, limited markets meet with limited success.  In order for DTV to succeed we believe the standards supporting DTV use in this country must have zero tolerance for such compromises."

In addition to ABC/Disney and NBC, nearly all major networks, group owners -- large and small, have submitted comments as well.  As with anything of this type, some of the comments had substance; others seem to be politically motivated, so the submitter could say that they had filed something.  The comments filed to date are probably the most representative of the broadcast industry in filings on any issue over the immediate past history of any FCC proceedings.  There is no question that the commission will certainly be under scrutiny by broadcasters, the public and Washington DC's lawmakers, alike. 

This opportunity certainly affords the FCC the platform on which they can regain some of the eroded respect they have cached over the last several decades as a willy-nilly, do nothing bunch of Washington bureaucrats with engineering and legal degrees.  We can only hope that they are up to the task.

Think not for one moment that the comments filed are the only correspondence been received by the Trustees of America’s airwaves.  Many major organizations have been sending open letters to FCC chairman William Kennard.  The National Association of Broadcasters (NAB) said that the FCC has "to take immediate steps to make the digital transition a reality."   These comments by NAB were in support of their position on “digital must carry,” cable compatibility and receiver performance standards.  The ink had hardly dried on the broadcasters association’s comments, when the National Cable Television Association issued a sharp rebuttal.

With some time remaining for comments to be filed, as of this writing, one can expect to see more of the same as the polarization in this issue solidifies, and the proponents and opponents unfurled their battle colors.  Many broadcast engineers have been following this event with great interest.  Typical of this interest can be found on a web page put on the Internet, as a service to fellow engineers, by Lee Woods, Director of Engineering at KOIN--TV, in Portland, OR.  There's little doubt that others have done a similar service.

In speaking with many of the television engineering managers across his great land of ours, most seem to “just want to get on with the business of getting a digital television plant on the air and being able to replicate current NTSC coverage.”  In seeking comments from the FCC, one person, who asked not to be identified, put it quite simply: "it isn’t over until it's over!"

Lee Woods web page, listing links to the comments filed to date, can be found at: http://pub1.ezboard.com/fdigitaltelevisionhdtvforumgeneralforum.

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Subj:  Linda Simmons
From:  Dave Hill   larcantx@aol.com

For some many years Linda Simmons, executive director of the Alaska Broadcaster's Association in Anchorage has been our friend and help when we travel and exhibit in Alaska.  She now needs a bit of help from those of us in the business and I would like to request a bit of space in the Newsletter that goes out to one and all to see what we can do for one of our own.

Thanks and kind regards, DAH

Forwarded by Dave Hill

 PLEASE read and respond ASAP!

As you know, our Alaska counterpart, Linda Simmons, has been fighting leukemia for the past few months.  The good news is, she is in remission at the moment and has been sprung from the hospital for the next few days.  The BAD news is, for reasons too complicated to go into here, she may not have insurance to cover her expenses, and may be looking at mega-multi-thousand-dollar medical bills when all is said and done.

Lou Munson, Jackie Lett and I are putting together a silent auction, to be conducted at the NAB Radio Show, to help Linda with her expenses.  We need your help!!!!!  We'd like to come up with at least 50 items to auction off.....AND we need help running this thing:

1. Suzanne Goucher is the contact for this, suzanne@mab.org.  DONATE  AN AUCTION ITEM, or two, or three.  Suggested value at least $50.  Gift certificates are good -- lightweight and portable.  Airline tickets, Disney World or Six Flags passes, hotel vouchers, lobsters-by-mail, free legal advice, what have you?  Work your contacts -- sponsors, exhibitors, your members, etc.  (BUT, see #2 below.)  Think about what Radio Show participants might want to bid on -- engineering services, a jingle package from JAM, a new station logo design, etc.  Get creative.  You could even dip into all those frequent flyer miles you've racked up at association expense! 

2.  [Please, no ball caps, t-shirts, tapes, CDs, etc.-- unless we're talking about a Paul McCartney-autographed Beatles CD collection, or the authenticated cap Nolan Ryan wore when he pitched his 7th no-hitter -- you get the idea.]   For more ideas, see the ASAE Foundation web page at http://www.asaenet.org/foundation/silent_auction/

DEADLINESeptember 12
By that date, I need to know exactly what we have in hand, so please notify me. (But don't wait until the last minute!)  If you are coming to San Fran, bring your stuff with you.  Otherwise, please mail it to me to ARRIVE NO LATER THAN Sept. 12 (MAB, 128 State St., Augusta, ME 04330).

***DONOR FORM:  By the first of next week, there will be a donor form on-line at the BEDA jobs website, www.careerpage.org, as well as at my website, www.mab.org--scroll to the bottom of the opening page and click on the butterfly.***

Jackie Lett is the contact for this, jlett2@earthlink.net.  Volunteer to be the "KEY CONTACT" for one of the vendors we all deal with -- ASCAP, BMI, Arbitron, RAB, ARNG, ShawPittman, etc., to see if they'd be willing to donate an item (or three). If you'd be willing to do this, contact Jackie. She will coordinate to make sure these folks aren't inundated by calls from all of us.  [But see "DEADLINE" and "DONOR FORM" above]

 3.  Lou Munson is the contact for this, lmunson@broadcasters.org. 
 WORK THE BOOTH.  We are working with NAB on securing space in the exhibit hall.  We'll need to set up a schedule for tending the auction exhibit.  Exhibit open hours are Wed. 9/20, 5-8 pm; Thur. 9/21, 10 am-6 pm; Fri. 9/22, 10 am-6pm.  If you'd be willing to spend a couple of hours, please let Lou know.  ALSO, if you have family or friends accompanying you to San Fran, we could use a few pairs of hands to get everything set up on Wednesday afternoon, 3-5 pm, while we are in our BEDA meeting.  We want to get the schedule set as far in advance as possible, so contact Lou ASAP if you or a loved one can help out at the exhibit booth.

 4.  CREDIT CARD PROCESSING:  Suzanne Goucher is the contact for this, 
suzanne@mab.org.  If your association can process MasterCard and Visa payments, would you be willing to bring a card machine and a bunch of  slips to San Fran, and to process the payments through your account?

 Thanks, all.  Isn't this what associations are all about?
 
 Suzanne Goucher
 Maine Association of Broadcasters
 suzanne@mab.org

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Subj:  See if you can remember...
From:  Authors name with held by request.

(ED Note:  It never hurts to reflect back to where we’ve been on our trek to DTV-land. Things do change and usually for the better.  Go ahead.  Date yourself too.)

Announce booths with live announcers
Smoke filled studios
When cars drove by the front of the studio while a live commercial was done.
How to load a PT-6 (and how fast it rewound)
Pop machines that dispensed bottles
Coffee shops and cafes with tableside juke boxes
How to actually tune a transmitter
The annual proof
Milk in Glass Bottles
A broadcast plant with NO transistors
Testing new tubes before putting them on the shelf
Beverages before cans
Meter readings every half-hour
Bakelite
Life before Color TV (or any TV)
Station frequency monitors
Party lines and only answering when it was 'your ring'
Remote broadcast equipment made by Collins
Life before counters and the BC-221
Newsreels and cartoons at the movies
Open wire transmission line
When music on AM Sounded GOOD
When AM car radios sounded GOOD
When FM meant Fine Music
RCA transmitters with sliding doors
Telephone numbers with a WORD prefix (WEbster 1265)
Broadcasting in Stereo using an AM and FM station or two stations
Peanut tubes
Howdy Doody
78 RPM records.
16 inch E.T.’s
Spots that come on E.T.'s
When ET meant something other than a little fellow from out there
S&H Green Stamps
Orbiters for your I.O.
Hi Fi (before Stereo)
Jensen Needles
Metal Ice cube trays
Conical TV antennas
Mimeograph Paper
Life before Copy Machines
Blue Flash Bulbs
Hoffman Easy Vision
Sylvania with Halolight
Ratheon broadcast equipment
Radio stations broadcasting parades
Gen-lock
2 inch Quad.
Gates consoles and transmitters
Western Electric Microphones, consoles and transmitters
Altec Microphones and consoles
Dumont TV equipment
"A" scopes
Washtub ringers
Bluing that had nothing to do with chroma
LSMFT
The Salt Shaker Microphone
When just about every radio station ran 5 minutes of news every hour?
When Gabriel Heater and the news was not an air conditioning company with your bill.
Muntz TV sets
Anon…….

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(ED Note:  We have brought up the issue of translators and replication of NTSC coverage any number of times here in the Tech-Notes.  Our web page even has a section on translators.  Nearly 1/3 or American television viewing is done via translators.  It is always interesting to hear from those out in the trenches about their concerns and what they are doing.

Subj:    Replication of our NTSC coverage - As we see it 
From:  LeBon G. Abercrombie,  Sr. Exec. VP/Planning & Development -- Pappas Telecasting Companies   LGA@PappasTV.com 

We believe that being wireless is a distinct advantage for OTA (over the air).  While we believe must-carry/retransmission consent is essential for the success of the DTV transition, it is by no means the only method we need to reach our viewers. 

As you may know, we have been an outspoken supporter of COFDM since witnessing the Sinclair tests last summer.  Many broadcasters around the country have multiple translators to extend their NTSC coverage.  Some stations have 15 or more translators.  Why should we think they wouldn't also use SFN's to extend their DTV coverage?  As a matter of fact, in many areas, it is extremely difficult to get translator frequencies.  SFNs would eliminate that problem. 

Our company has made every effort to "maximize" DTV coverage beyond the original power and coverage levels allocated by the FCC.  However, those "maximization" applications have languished at the FCC for nearly a year, due to their inability to process them. 

LGA 

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The Tech-Notes are published by Larry Bloomfield and Jim Mendrala. We can be reached by either e-mail (above) or land lines (408) 778-3412, (661) 294-1049 or fax at (419) 710-1913 or (419) 793-8340. The opinions expressed herein are those of the individual authors and do not necessarily reflect the opinions or positions of their friends, employers or associates.  If you wish to remove yourself from this list, send an E-mail to: hdtvguy@garlic.com.  In the subject area put the word Remove. 

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