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DTV Tech Notes

% Larry Bloomfield & Jim Mendrala

(408) 778-3412 or (805) 294-1049

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February 15, 1999  DTV Tech Note Ė 025

Sharing experiences, knowledge or anything else relating to DTV, HDTV, etc., with your fellow engineers: That's what we are all about. We will send this to anyone asking, just E-mail us. There is no charge for this Newsletter.  Welcome to all new subscribers.  Weíre now over 235.  If you are receiving this newsletter and want to get off the list, just e-mail us that request. We hope everyone will participate in all ways with comments, experiences, questions and/or answers. This is YOUR forum!   Past issues are available at:  WWW.SCRI.COM

Digital Super Bowl Party

By Jim Mendrala

On January 31st Digital Arts & Engineering held a Digital Super Bowl Party at B.B. Kings Blues Club on City Walk, Universal Studios, CA. The idea was to show to producers and directors of television and music video content state of the art DTV (Digital Television) from a consumer standpoint.

Several manufacturers including Hitachi, Panasonic, Digital Projection and Stewart Filmscreen participated, as well as The Good Guys and Audio Rents. The Good Guys provided the DTV Panasonic DTV receiver and Audio Rents a Yamaha Dolby AC-3 decoder.

The demo was set up with two living room settings using the new Hitachi DTV ready, model number 60SDX88B, 60 inch sets.

A 12 ft. by 9 ft. screen with a 15 ft. diagonal provided by Stewart Filmscreen was set up on B.B. Kings stage and the image on the screen was projected from the balcony via a Digital Projection Power 7gv projector.

The projector with itís 3 chip Digital Micromirror Device (DMD) provided 6,500 lumens on the screen. Thatís much brighter than what you see in most theaters.

Before the game, one Hitachi set was displaying the images and sound from a standard DVD disc player in the wide screen mode. The video from the DVD was fed to the set using the S-Video connection. Audio was in 5.1 channels. The center, left and right speakers were in the set and two external Tannoy speakers powered by the Yamaha amplifier provided the surround sound.  There was provisions for a sub-woofer but we didnít use it. The rumble and other low frequencies sounded okay though. With the line doubling used in the Hitachi, the picture looked very good and some viewers mistakenly thought it was HDTV.

With an off air antenna, the NTSC pictures on the Hitachi did not look as good as on a standard NTSC receiver. The problem was that the picture had ringing artifacts in it. Since the same antenna was used to supply the other TV sets, it was interesting how the same stations looked on the various receivers fed by the same antenna.

For the Digital Projectionís Power 7gv projector, three video sources were used. One was the Y, Pb and Pr output of a Panasonic TU-DST50 DTV receiver. A second was the RGB output of a W-VHS analog HDTV player, and the third was the composite output of an old Betamax VCR. The Betamax was  used as a tuner for the game which was broadcast only in standard NTSC but with stereo sound over Foxís Channel 11 in Los Angeles.

Amazingly the best NTSC picture displayed was from the old Betamax VCR composite output (used as a tuner) and projected onto the big screen using the Digital Projectionís Power 7gv projector.

The 50 inch NTSC TVís fed from the cable system at B.B. Kings Blues Club were quite a bit noisey, like fringe Grade B.

The 60 inch DTV-ready Hitachiís, when tuned to the NTSC channels, had ringing in the picture which seemed to be related to the comb filter used to filter out residual 3.58 MHz. However, the DVD using the S-Video connection from the DVD player looked very clean.

When the Panasonic TU-DST50 DTV receiver was tuned to the 5 DTV stations on the air in Los Angeles, there was excitement and disappointment. The DTV receiver, when switching from channel to channel, took about 5 seconds to lock up and display a picture.

KCBS-DT was running a HDTV travel type of program about Los Angeles. It was shot in HDTV and was outstanding. It looked as good as a movie on the 12 ft. by 9 ft. screen. The image was letter boxed by unused pixels above and below the image. (The native resolution of the Digital Projectionís Power 7gv is 1024 by 768 in a 4x3 aspect ratio. The HDTV picture was down converted to fit this native display.) The rear screen projected Hitachiís displayed a very good picture also, but the image was not as sharp as Digital Projectionís projected image. It was more like the DVD image.

KTLA-DT and KNBC-DT were up converting the regular NTSC programming and, compared to KCBS-DT, were disappointing. Even though KTLA-DT was the first on the air with DTV and HDTV and broadcast the Rose Parade in HDTV, a call to them revealed that they had no HD D-5 to play any HDTV on. The DTV broadcast did not look as good as the same NTSC broadcast viewed through the old Betamax VCRís composite output and projected by the Power 7gv.

KABC-DT was not on the air before the game.  Neither was KCOP-DT when we selected their channels.

DTV after 3 months is still in its infancy.

The antenna, a Radio Shack VU-75XR, had a clear shot at Mount Wilson where the DTV signals were emanating from. The output of the antenna was amplified by a Radio Shack signal amplifier p/n 15-1108. It has a maximum of 20 dB of gain on the UHF channels and 25 dB on the VHS channels and is adjustable. The need for the antenna-mounted signal amplifier was to make up for the loss of signal through 350 feet of RG-6 coax and the four way splitter used to fan out the signal to the two Hitachiís, the DTV receiver and the Betamax VCR. Pointing of the antenna was done by tuning a small portable TV, connected directly to the antenna, to channel 34, KMEX-TV and Channel 11, KTTV-TV. Ghosting on channel 11 was minimized by rotating the antenna slightly away from Mt. Wilson and more towards Mt. Hollywood. There was plenty of signal at the antenna as we were only about 15 miles away, as the crow flies, from Mt. Wilson.

Now, I know the Digital Projection Power 7gv is a very expensive projector, but it was used as a reference point to compare what is being broadcast to what is being displayed on the consumer DTV sets.

The HDTV that KCBS-DT was broadcasting was superb. Everyone was awed by the clarity even when blown up to 9 ft. high and over shooting the 12 ft. screen by 2 ft. on either side. We had to put up some black polyvinyle on the windows to darken the light spill into the living room settings and help the rear screen projection Hitachis cope with the ambient light.

Everyone agreed that the HDTV picture was very good -- no noise, no ghosting, excellent color, no obvious MPEG encoding artifacts, and CD quality sound. The picture was almost lifelike. KCBS-DT did a very nice job. KNBC-DT was the worst. Even though they were not broadcasting an HDTV picture, the DTV transmission was full of NTSC and MPEG artifacts. Perhaps this was because they were taking the composite feed to the NTSC transmitter and using that signal to be encoded by the MPEG encoder to DTV instead of component video. KTLA-DT was a little better but still not quite as good as their NTSC transmission. The DTV pictures did have excellent signal to noise and no ghosting whatsoever.

It was planned to have a RCA DSS receiver to view the Super Bowl. The night before the event everything was working fine but Sunday morning it rained and the main processor in the DSS receiver failed. This, bgy the way, was the only time that the DSS receiver was not plugged into a surge protector. RCA says that if you buy there surge protector they will extend the warranty on the DSS receiver to 3 years.

The W-VHS HDTV player looked very good although it was analog. A few thought it was film.

My conclusion is that HDTV broadcast by DTV on a big screen is awesome. Up-converting NTSC to digital to feed the DTV transmitter is not a very good idea. If SDTV is to be transmitted it should be sent to the transmitter in component form not composite and should not be upconverted to HDTV as the receiver outputs the image to either 480p, 1080I anyway. Decoding NTSC to feed the MPEG encoder with other than an expensive NTSC decoder is a visual disaster.

DTV is new to the terrestrial broadcaster. In a several more months, the broadcaster should be transmitting a picture at least as good as the DSS Satellite people have been doing for the last couple of years.

Things are on the move at SMPTE

By Larry Bloomfield

Information has come our way that indicates that SMPTE is making some major changes in their committees.  An inside source says it all has to do with the slowness in establishing standards for digital television and ANSI's dim view of how SMPTE has been approaching the establishment of their standards, in general.  It sure seems strange that they would wait until the ship left the dock before deciding the crew needed to be changed. 

It's almost like SMPTE was oblivious that digital television was going to be launched this past November, but on the other hand there are those who think the change is very long in the tooth in coming.  Despite many significant changes in both the film and television industries, SMPTE is essentially the same organization as when it was founded back in the late 20's.  A chair of one of the new committees said that until this major restructuring, SMPTE was a "good old boy's " organization that got together to reminisce rather address new technology. 

There is little question among those who have kept abreast of the technology that most in the industry have not.  The seeming lack of direction and understanding in the area of digital television is truly scary.  Proof of this can be seen in recent surveys conducted by such reputable firms as SCRI.  A good look around would certainly point out that some of our most trusted suppliers are trying to take advantage of this situation by pushing the industry in directions that it may not necessarily be in its' best interests and all for their corporate bottom lines.          

It certainly is better that the wake up call came now instead of later when more of the industry had gone further down the digital path.  More information on this subject will be forth coming as we can get people close to the situation to talk about.  It seems SMPTE doesn't want to wash their dirty laundry.

Both Jim Mendrala and I are members of SMPTE and since we who write for the DTV Tech Notes have no advertisers to please or any other allegiances other than the highest of engineering standards, we'll make every effort to keep you informed as this situation develops.  What to see it for yourself?  Go to the SMPTE meetings.


Is the Peacock Changing Colors?

It was only a few months ago that a longtime friend of my, from back in the days when we both worked at the Peacock factory (NBC) in Burbank, shared with me that he'd recently walked through our old, but familiar, "stomping grounds," at the junction of Olive and Alameda in Burbank.  He said:  "It seemed like a morgue."  He told me that yes there was production going on, but the other operational areas seemed all but abandoned.  SkyPath, which he and I had help build, was totally dark.  Is this all part of something in the wind? I've heard rumors, seen stories and been told by people in the know, that GE has been positioning NBC for possible sale.

Another friend, who is in a position to know, at NBC in New York, and has asked to remain just that, told me that; "NBC, and all of the other nets had big layoffs," around the end of September.  He said, "We lost most of our real engineers. CBS laid off their news dept and ABC did layoffs from top to bottom."  Sounding like my Burbank friend, he said, "The place is very empty now, very depressing now that everyone has gone. It is like it was when I worked on the weekends.  Lot of people getting into other things, both the people that were laid off and the people that are still here." 

In further conversation, my source mentioned that GE had offered 49 percent of NBC to Sony Picture Entertainment.  I hope General Sarnoff doesn't turn over in his grave.  He continued, saying , that GE goes into these "partnerships" offering minority ownerships.  He did say that he wasn't sure if it the stations were included in this offer or not.

It will be interesting to see what happens. Oh.  A point of trivia.  It was NBC who had the Kate Smith Show; remember -- "When the Moon Comes Over the Mountain."  It was this vocally gifted, rather large lady who was the inspiration to the expression that:  "The fat lady hadn't begun to sing."  My sources tell me she's on the way to the microphone.


Beyond the Label

Character Generators (CG) have been around for a while and aren't particularly newsworthy; unless the one you're talking about is new, different and does a lot of really "neat things."  That is the case with this "new box" from Pinnacle.

Within the past year or so, while Chief at my last station, I looked at quite a few CGs trying to find a replacement for an aging workhorse that was becoming increasingly more undependable: an all too familiar story, I' sure.  I had almost every known manufacturer, or their rep, stop by to show me their "goodies."  As an NBC affiliate, we wanted to look like them, but hardly had the budget to cover the cost of the paperwork the Peacock factory used to buy their CGs with.

This fall, when I was invited to have a "look-see" at Pinnacle's new FXDeko, I was truly impress with what I saw and all that it does; shatters, 3D space rotations, warps into position, and more.  At the risk of sounding like a product review or infomercial, I'd like to share with you only the things that impressed me the most and let the salesmen take care of the rest.

Besides being a character generator that will handle most any font library going, including Chyron's, it's also a digital video effects (DVE) generator that will take two channels of external video and put them though the same gyrations it puts the fonts through.  It interfaces with other systems such as equipment made by Quantel. 

Speaking of fonts, I had a very difficult time a few years back finding a CG that would handle non-Roman language fonts.  Although most places don't have the requirement, it's nice to know that the FXDeko supports Arabic, Hebrew, Cyrillic, Chinese, Japanese, Korean script and probably a few I can't remember.  You never know when you might get a job requiring one of those systems of script.  

The built-in Frame Grabber lets you snag images from video clips, etc., extending your Creative Services' ability to come up with unique and good looking local material while retaining that certain "image" and still looking distinctively different. 

Being NT based, with both hard drive and standard 3.5-inch floppy drive for memory, it's compatible with other similar based equipment.  The "box" is reported to be DTV ready (whatever that means).  It runs in all currently popular analog formats; NTSC, PAL S-Video, etc.  Inputs are RGB, YUV or serial D1 and the outputs are the same plus SMPTE/EBU and key.

The FXDeko lists out at about half the cost of the "industry leaders" comparable top of the line.  I'll let you go away trying to figure out who that is.  I'm purposely not going to mention price as we all know the FXDeko will ship for various prices, depending on who you "strike a deal" with.  Good luck and good looking.

Check out Pinnacle's web site at:


Local into Local Soon?

The headlines read: "Local TV On Satellite Hires Veteran Broadcaster as Chief Operating Officer"

Since there are over 1600 television station in the USA, it would seem to me that Local TV on Satellite might be a very ambitious venture for these folks. Since some of the cable folks are balking at the new DTV/HDTV formats and are iffy about having to carry more than one of the two TV station from the same operator in the same market, maybe this is an answer.  It may also be an answer to the problem of translators and what's to become of them.  Remember that many of the communities in the and West of the Rockys depend on translators for their TV service.  Portland, OR stations along have anywhere from 50 to 75 translators each.  In the 202nd market, Bend, Oregon, I had 8 translators when I was Chief Engineer there, but with the number of stations to be considered across this fruited plane, this is quite an undertaking!

According to the press release, John H. Hutchinson, a veteran broadcasting executive will join Capitol Broadcasting Company, Inc. as Executive Vice President and Chief Operating Officer, a new position.

Hutchinson, will have the job of implementing LTVS's plan to deliver all local television stations in the U.S. via satellite, giving consumers alternatives to their cable providers and translator systems. He joins LTVS after 28 years with Jefferson-Pilot Communications Company, the last seven as President of the Television Group and General Manager of WBTV in Charlotte, N.C. During his career, he's held a variety of broadcast management positions. Hutchinson is a member of the Television Board of Directors of the National Association of Broadcasters and a District Representative on the CBS Affiliates Advisory Board. He holds a BA degree from the University of North Carolina.

Jim Goodmon, President and Chief Executive Officer of Capitol Broadcasting Company, Inc., said, "John Hutchinson's extensive broadcasting experience will be a huge asset as LTVS develops its business plan to provide meaningful competition in the multi-channel video programming market."

When asked about his new position and about LTVS, Hutchinson responded, "I believe LTVS has the technological 'local-to-local' solution that broadcasters and Direct Broadcast Satellite (DBS) providers need to give consumers greater choice, better service and lower prices. I look forward to making local television via satellite the industry standard."

Local TV on Satellite, LLC was founded in 1997 by Capitol Broadcasting Company, Inc. and its subsidiary, Microspace Communications Corporation, to develop and implement a plan to deliver all local television stations in the U.S. via satellite. Using "spotbeam" satellite technology, LTVS would make DBS providers fully competitive with cable, providing quality transmission of all local television stations in all local markets. Current laws prohibit DBS providers from carrying local stations. Congress is considering legislation this session that would change all that, guaranteeing all consumers access to local programming from all providers.

CONTACT:  Capitol Broadcasting Company, Inc.  James F. Goodmon 919-821-8504


Spectrum for Lat-ta-num

If you're not a "Trackie," then you may not know that lattanum is the intergalactic money of the future and what it will take "a lot of" if you want a frequency to operate on in the future.

The auctioning off, to the highest bidder, of frequencies and spectrum is at hand, and will be the way of the future, in all services under the auspices of the FCC.  The successful party, who vied for an available frequency, will no longer be a matter of the most qualified or necessarily worthy, but the one with the most bucks or latinum.

Many broadcast engineers and technicians are also amateur radio operators.  I'm no exception, KA6UTC.  Those who are may recall, not too long ago when a large chunk of the 220 MHz amateur band was wrestled away from them by the "guardians of the air waves," the FCC.

Want to know what happened to it?  Read on!  In report number WT-98-36, the Commission, in a harbinger of things to come, announced they had, in about a five-week period and in their 17th auction, raised $21,650,301.00 in net bids after 173 rounds for the 220 MHz service.  

I can't help but wonder if Daddy Warbucks, of Little Orphan Annie fame, had been an amateur radio operator and had bid $22 million, if we couldn't have retain that spectrum for amateur radio use?

For more heart throbbing details see the FCC web site at:


Pluto's HyperSPACE

In a recent survey I took of broadcast engineering managers in the top 10 markets, they told me, by the numbers, that one of the biggest problems they were having making digital TV a reality was the availability of equipment.  Since many television stations have made the transition to an analog video server as their main stay for commercial play back, program delay and other familiar uses, it has become an important item to be considered for the digital plant as well.  News of such a device certainly deserves mentioning.    

When someone told me that "Pluto" had developed such a device, all I could thing of was the mythological Roman god, the ninth and farthest planet from the sun or thoughts of the gangly, floppy eared Disney dog, but certainly not a video server. Was I ever surprised!

I wasn't too far off track when I thought of the planet because Pluto has developed, what they are calling, The HyperSPACE HDCAM.  Now the HDCAM part of the name comes from Pluto's association with Sony.  The HyperSPACE HDCAM is a playout server designed to be used in HDTV broadcast applications.  It is random-access, so it should work well with station automation and can be put to work as a Hi-Def disk recorder for post-production applications. 

The way the project went together was that the R&D team at Pluto Technologies International used the HDCAM compression technology developed by Sony.  The product will allow broadcasters, cable operators, Direct Broadcasters and Post-productions houses to operate in one environment (HDCAM) minimizing "generational" video quality loss that improves the on-air product. 

The HyperSPACE HDCAM is designed as a "plug and play" device and is initially being offered in several packages ranging from a simple server/encoder, for reliable storage and random access to media, to larger systems that include an editor, switcher and VCRs.  No mention was made as to video formats accommodated.  For additional information, visit either the Pluto web site at or the Sony web site at     


 The DTV Tech Notes are published for broadcast professionals who are interested in DTV, HDTV, etc., by Larry Bloomfield and Jim Mendrala. We can be reached by either e-mail or land lines (408) 778-3412, (805) 294-1049 or fax at (805) 294-0705.  News items, comments, opinions, etc., are always welcome from our readers; letters may be edited for brevity, but usually not.

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