The HDTV movement began in 1969 from within Japan's huge public broadcaster, NHK (Japan Broadcasting Company). NHK must, by Government decree, spend a small percentage (less than 1/2 of 1%) of their multi-billion dollar income for research and development in television for the public benefit. They do so in cooperation with the electronic manufacturers of Japan. Ventures from this cooperation become commercial products from the manufacturers.

HDTV bounced on to the world stage in 1981 with demonstrations given by NHK in the US and Europe. The goal of the early movement was to achieve an international agreement on a single worldwide production standard. The first proposed HDTV production standard-with parameters of 1125 scanning lines and 60 fields-came out of the Japanese research. The parameters were set so as to make conversions to all existing analog transmission standards around the world as easy as possible. Europe and other 50 Hz regions were slightly disadvantaged with these parameters due to the 60 Hz field rates in the Japanese proposals. The Japanese proposal was endorsed by the US. The hope of a single standard was sunk in 1987, the result of protective politics in Europe. Europe offered their own standard as the single standard and the world fell into two camps-one with 1125/60 parameters and the other 1250/60. That sapped much of the strength from the movement.

First transmission demonstration for HDTV appeared in 1985. This solution from Japan (MUSE) required 8.3 MHz from a satellite and suffered a softening of the image when in motion. Europe stepped up their research and development to gain parity with Japan and delivered their own HDTV satellite broadcasting system two years later (HD-MAC). Both systems, while digital in much of their internal operations, were in the end analog and fell on hard times when the whole world decided it must go digital. The Japanese were determined to be first every step of the way and introduced MUSE HDTV as a commercial product in 1991. Eight hours a day experimental broadcasting fed a very weak market. The MUSE system has taken considerable heat and been declare obsolete before it was ever launched. Still, this analog system is slated to run until the year 2007 when a new satellite will be launched with increased capacity. At that time a conversion to all digital will be made. This left the HDTV movement gasping for air as still another apparent misstep showed up on the ledger for this unlucky technology.

The US was on the verge of industrial paranoia in the late '80s and early '90s. Worry that Japan and Europe were sure to gain a technical advantage with HDTV swept through Washington. President George Bush responded by ordering his FCC Chairman, Al Sikes, to get America in the lead.  Broadcasters had by 1987 asked the FCC to look at the HDTV question, freeze spectrum allocations in the broadcast bands, cause a HDTV transmission system to be created and tested, and then allocate spectrum to broadcast it if more was needed. Prior to assuming duties as Chairman of the FCC, Sikes had been head of the NTIA, an advisory organization to the White House on telecommunications policy. He was widely regarded, knowledgeable, and had extraordinary influence. He was our leader and the HDTV movement followed every word. But the word was transferred out when the Clinton Administration was on the verge of coming in. Sikes dove for cover within the executive offices of The Hearst Corporation in NYC and a relative unknown, Reed Hundt, assumed the chairman's office. Hundt had little reputation as a technology expert and the FCC lead was left to the influence coming from outside its office. HDTV was no longer the thing to save American face, that being replaced by the internet.

The Grand Alliance system can do more than encode and decode HDTV. Within a 6 MHz spectrum a station could choose lesser resolution and allocate bits in the 6 MHz spectrum for 4 or more additional programs in a lower quality (equal to studio grade NTSC). Additionally there is a data-only capacity to the GA system. This is designed in for still-to-be-found ancillary data services, such as stock market information delivered to a TV set or PC.  This flexibility has raised concern that HDTV will be abandoned in favor of more program services, but no solid business vision has emerged on how to do that. More importantly, Congress has smelled money in the water and auctioning spectrum that is used for non-traditional public services has become a popular idea. This threat of auction of spectrum has made the broadcasters to say, oh, yes, we always thought HDTV was the primary purpose for the new channel. "Get the spectrum free and worry later what to do with it," has become the underlying strategy for today.

For HDTV to come to the home, a complete revolution in television technology will have to be completed. Nothing remains the same. The technology will inevitably induce a revolution in the business of television itself with a probable change in powers. No one can be left unaffected-not the program producers, the signal providers, the transmission providers, the advertisers, the manufacturers, the retailers, and certainly not the end users. Each will need to adapt to the new to avoid obsolescence. It is a system designer's dream. The great danger is that the movement gets off to a half hearted commercial start and is dragged back by the inertia of the old. Then it would pause in mid air and careers and investments would come crashing down. It is a difficult task, full of risk unless there is an orchestrated effort where the manufacturers, the program suppliers, the signal's providers, the alternate media groups, and the end users all play the same tune together.?

Facts about DTV
By: Audio and Video Authority at http://avauthority.com/HTML/News1.htm

* FCC has mandated digital terrestrial broadcasts in all markets by 2002.

*HDTV can be: SDTV with resolution comparable to DBS satellite TV available now; or  HDTV with twice the scan lines & resolution of current TV's. A broadcaster may choose to offer SDTV and provide multiple program offerings on the same bandwidth required for true HDTV.

* The Audio standard for HDTV is DOLBY DIGITAL AC-3

* Your current set will not become obsolete, It simply won't deliver the performance of an HDTV set.

* HDTV compatible or "up gradable" sets are not being & have never been sold, the only exceptions are a select few high end front projection systems.

* No announcements have been made regarding cable or satellite broadcast of HDTV.

* HDTV is produced in a 16 x 9, wide screen aspect ratio (your current set is 4 x 3) this more closely resembles a movie screen.

* The first HDTV sets will be big screens in the 8000 range.

* HDTV will be offered in Big Screen sizes initially,the benefits diminish on smaller sets, and the costs are prohibitive.
 

Always the path of American destiny has been into the unknown. Always there arose enough reserves of strength, balances of sanity, portions of wisdom to carry the nation through to a fresh start with ever renewing vitality.
-Carl Sanburg

What is HDTV, and what does it do?
 

By the year 2006, and perhaps even later, the FCC will order all analog TV transmitters off the air, and television broadcasting will have switched to digital transmission.  High Definition Television will produce consequential improvements relative to the current National Television Systems Committee's analog standard.  HDTV is so far a high-tech buzzword to many Americans.  But high definition television will revolutionize modern television the way color TV did when it was first introduced in the 1950?s.

HDTV will improve:

 * Picture clarity.  It is an increase of about 400 to 500 percent.  With NTSC television, the screen is divided into a grid of 340 by 420 pixels, or picture elements.  An HDTV screen's grid is 720 by 1280 pixels, producing a much higher resolution.  Higher - resolution picture.  This is the main selling point for HDTV. Visualize 720 or 1080 lines of resolution rather than today's 525 (in the U.S.) or 625 (in most of Europe).

 * Motion.  HDTV can run at 60 frames per second, twice the frame rate of NTSC, so figures move more smoothly on screen.

 * No ghosting.  HDTV eliminates the ?ghost effects? and snow in the background that sometimes appears in NTSC television broadcasts.  ?With the new system, either you see it or you don't see it, and when you do it's spectacularly clear?, stated Jae S. Lim, head of the MIT Advanced Television Research Program.

 * Better aspect ratio.  The width to height ratio on current televisions is 4 to 3, and the dimensions were set 40 years ago when motion picture screens were more square.  The aspect ratio for HDTV sets is 16 to 9, and the wider the screens allow for panoramic filming.  Also, because HDTV?s have higher resolution, television screens can be bigger.

  * Higher audio quality.  HDTV is equipped with four channels of CD-quality audio, unlike current sets.  Digital surround sound.  HDTV broadcasts will be encoded with Dolby Digital (AC-3) audio, featuring six separate audio tracks.  Each track can be sent to a different speaker, allowing detailed and realistic surround sound.

     * Additional data. Although the term HDTV specifically refers to picture quality, digital signals will also contain a data channel, which could carry related information, such as scrolling text or computer software downloads.

Higher Audio Quality

The days of vinyl are long gone. I'm not talking about the upholstery in dad's sedan. Instead, I'm getting nostalgic about those old 78 RPMs spinning on the record player and the oh-so-careful lift of the needle. Stereophonic sound!
When CD's appeared on the market, most people were skeptical about the silver discs, but the sound was great. Digital audio recordings on CD have a wider frequency range, finer sampling, and they won't wear down with age (it stays perfect until something like a scratch damages the data). Almost everyone can hear an obvious improvement.
 
 
 

HDTV will broadcast everything with the Dolby Digital/AC-3 audio encoding system. It's the same digital sound used in most movie theaters, DVDs, and many home theater systems since the early 1990's. It can include up to 5.1 channels of sound: three in front (left, center, and right), two in back (left and right), and a sub woofer bass for a sound you can feel (that's the .1 channel). Sound on digital TV will be "CD quality" with a range of frequencies lower and higher than most of us can even hear.

No ghosting

Remember the days before cable television when someone in the family would assume the job of antenna contortionist? To improve that ephemeral picture to a viewable standard, they would skillfully adjust the alignment, length, and height of the antenna to get the best possible picture. But sometimes the picture would still display a foggy double image or ghostly images of the adjacent channel.

A basic natural law that our technology can't overcome is the weakening of television signals as they travel away from the transmitter. Both analog and digital signals get weaker with distance. However, while the picture on an analog TV slowly gets worse for more distant receivers, a picture on a digital set will stay perfect until the signal becomes too weak for the receiver to pick it up. By perfect, I mean the picture on the TV is exactly the same picture the broadcaster started with at the transmitter.

*Real advantage*  Digital HDTV can be integrated with other technologies, like personal computers.

The convergence of television and computers is going to take a major step with digital broadcasts.  Data will be sent along with video and audio. How we'll use the data is still largely unknown, but one of the more practical options is the set-top box.
Its name is very descriptive.  It will probably be a box that sits on top of your digital television, just like many VCRs do right now.  Also, just as your VCR does, a set-top box will take input from the cable connected to your antenna or cable service, and output to your television.

The set-top box will process the data sent with the broadcast, storing some of the data and executing applications.  How it will do all this is still being developed.  There are a few steps in the process which still need to be defined and implemented, including the format of the data, the set-top box's operating system, and the application environment.
At this point, it looks like these set-top boxes will be based on something like Windows CE or Java.  No matter which system is chosen, though, TV is becoming an interactive experience with endless possibilities.

When is it coming?

Digital Broadcast Timeline:

April, 1997
FCC gives broadcasters $70 billion worth of spectrum to broadcast digital alongside analog until 2006. FCC also mandates that in 2006 all broadcasts must be fully digital.

November, 1998
PBS, ABC, NBC, CBS, and Fox are committed to broadcasting digitally in the top ten U.S. markets (30% of viewers) by Nov. 1.

May, 1999
Broadcasters must have digital stations in top 30 U.S. markets (50% of viewers).

2006
Broadcasters must relinquish extra broadcast spectrum and broadcast only digital.
 
 

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