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First, I admit that I haven't been following this topic for a couple of years.

Just to be safe, let's look at a site you won't doubt instead.

The target date set by Congress for the completion of the transition to DTV is December 31, 2006. However, that date may be extended until most homes (85%) in an area are able to watch the DTV programming. At that point, broadcasting on the analog channels will end and that spectrum will be put to other uses.

That answers the question of when phase-out occurs. The broadcasters must already be transmitting digital before 2006. (The other article linked below has a timeline)

And how do they know when the threshold is met? I don't know, but I noticed this little piece:
"A broadcaster can also use DTV to provide interactivity and data services that were not possible with analog technology."

On the topic of new sets:
Will I Need a New TV?
Your current television will work as it does now until analog broadcasting stops. Under federal law, analog service will continue until DTV service and equipment are widely available. Even after the transition is over, your current TV will not become obsolete. A converter box can be used to receive DTV signals and change them into the format of your current television. Converters for over-the-air broadcasts are available at retail stores.

I'm having a hard time finding these converters through internet searches. If a couple million households will need to buy these, I would assume more interest. The cynic in me is saying that it's probably better business to introduce a customer to a shiny new TV rather than to a small accessory. And from what I've found, the converters are all $100+.


I also noticed this site. The timeline halfway down gives some interesting highlights like:
"In November 2001, following the World Trade Center disaster and in consideration of the country's economic downturn, the FCC threw a huge bone to broadcasters with a loosening of the DTV deadlines."

It also mentions some sort of a timetable for when stations needed to comply with transmition, but I don't know what to make of it with statements like:
"Financial hardship" may now be an acceptable excuse for missing a deadline.

However, all dates listed there are before 2006.

The network also received recognition for providing the "Best DTV Sporting Event" for its HD broadcast of the 2001 Superbowl.

You forgot the 'i'. I'll take 480p over 1080i any day.

Is there a reason for that? The only comparison I could find in short order was here, and they seemed to think 1080i was better than 480p.

One might come away from a first reading of this report thinking that the differences between the two are now only modest and, indeed, often favoring the 8-VSB. The results certainly do not give COFDM a sweeping victory, which its proponents had long-predicted. The 8-VSB did better than most had thought it would.

COFDM is clearly superior in large Single Frequency Networks that are used in Europe (Last time I looked, the USA wasn't Europe).
...
PBS will not support efforts to test COFDM as a replacement for 8VSB. The issue has been examined before, and based on technical factors 8VSB was chosen over COFDM. More recent analysis indicates the decision was the proper one.

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. (once again - this isn't Europe)

Each transmission system has strengths and weaknesses. COFDM requires higher transmitter power output than 8-VSB for similar coverage. Higher power not only increases costs to broadcast stations, it raises the specter of excessive interference with existing analog service. This goes against clearly established public policy
...
The 8-VSB modulation scheme was chosen for reasons that far outweigh its multipath performance. The reasons remain valid, especially in the U.S., where the terrain and market structure call for performance characteristics quite different from those in most of Europe.
...
Canada, Argentina, South Korea, and Taiwan have all chosen to use 8-VSB for terrestrial broadcast of DTV as part of the ATSC standard, and it is under consideration by many other countries as well. (I guess you didn't really mean "The Rest Of The World)

One might come away from a first reading of this report thinking that the differences between the two are now only modest and, indeed, often favoring the 8-VSB. The results certainly do not give COFDM a sweeping victory, which its proponents had long-predicted. The 8-VSB did better than most had thought it would.

COFDM is clearly superior in large Single Frequency Networks that are used in Europe (Last time I looked, the USA wasn't Europe).
...
PBS will not support efforts to test COFDM as a replacement for 8VSB. The issue has been examined before, and based on technical factors 8VSB was chosen over COFDM. More recent analysis indicates the decision was the proper one.

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. (once again - this isn't Europe)

Each transmission system has strengths and weaknesses. COFDM requires higher transmitter power output than 8-VSB for similar coverage. Higher power not only increases costs to broadcast stations, it raises the specter of excessive interference with existing analog service. This goes against clearly established public policy
...
The 8-VSB modulation scheme was chosen for reasons that far outweigh its multipath performance. The reasons remain valid, especially in the U.S., where the terrain and market structure call for performance characteristics quite different from those in most of Europe.
...
Canada, Argentina, South Korea, and Taiwan have all chosen to use 8-VSB for terrestrial broadcast of DTV as part of the ATSC standard, and it is under consideration by many other countries as well. (I guess you didn't really mean "The Rest Of The World)

I looked for a simple, factual link and couldn't find one

Of particular concern is that current displays which do not implement a copy protection standard (because one has not yet been fully settled on) will be unusable with future digital sources (tuners, cable boxes, satellite receivers, DVD players, etc.) which do implement HDCP or whatever.

Mitsubishi says:

We will engineer and manufacture the upgrades necessary so the television you purchase today can be made compatible with near-future advances in digital television and digital interconnectivity. Specifically, we promise that you will be able to have your television upgraded, at a reasonable cost, to include an off-air HDTV tuner, a cable TV tuner (for unscrambled programming), an IEEE 1394 (FireWire®) connection, HAVi system control, and 5C copy protection.

I seem to recall a while back there was an uproar about the original wording of the Mitsubishi promise, something to the effect of the upgrades not costing you more than $1000 (it now reads "at a reasonable cost"), and that the upgrades would be made only if feasible. That particular link, I cannot find. It probably was on the AVS Forum.

I am close to purchasing a new HD-ready set myself and I've been following the market closely for the past few months.

First, you'll probably want to read some of the threads on the AVS Forum in the HDTV Hardware (a lot of good set top box info here!) and HDTV programming forums. Another good source of info on specific sets is the Home Theater Spot. Finally, if you want some perspective on the industry check out Mark Schubin's Monday Memo. It's published weekly.

I think it's a pretty good time to buy because:

• Prices on sets have fallen dramatically.
• Programming is really starting to become available. Cable & Broadcasting says there is 500 hours of HD available in the US per week.
• The picture does look tremendous!

Almost none of the sets or set top boxes you can buy today have a DVI or Firewire interface. These interfaces will enable set top box to talk to the TV and decide if it is a display device that is allowed to get the full 1080i resolution of a HDCP encrypted broadcast.

This won't be a problem if your set has a built in tuner that does HD or if your manufacturer is promising to upgrade your set to meet whatever standard gets decided on (and you don't mind replacing your set top box). That's why you probably ought to check out the Mitsubishi sets before you make a final decision. I don't work for them, invest in them, etc. I just like the fact that they are promising to upgrade whatever set you buy from them today via a plug in module that they'll sell for less than $1000.

Anyway, that's my 2 bits. Good luck!

Generally pretty good scoop. However, the Wired article got way too freaked out about the non-issue of interlacing. Also, from the comment above:

Note how NTSC defines one picture standard, but HDTV defines 18 (all of which must be supported by a TV in order for it to be sold as an "HDTV")!

This is pretty much a non-issue as well. The ATSC Table 3 standard basically calls for 5 different resolution/aspect ratio combinations:

• 1920x1080 @ 16:9 (HDTV)
• 1280x720 @ 16:9 (HDTV)
• 704x480 @ 16:9 (wide-screen Standard Definition)
• 704x480 @ 4:3 (Standard Definition)
• 640x480 @ 4:3 (VGA compatible)

The other variation is the frame rate. This is not a receiver issue. The receiver has no need to know the frame rate. It simply receives the data and jams it in the frame buffer.

It's the MPEG encoder which cares, because it must dynamically adjust the precision of the data stream to keep the average frame rate of the encoded data stream exactly equal to the frame rate of the source (24 fps for film, 30 fps for video, etc.).

Although both the MPEG encoder and the receiver need to be aware if the data are being presented in interlaced scan lines, interlacing of the data is unrelated to whether the display is interlaced.

A nice link: Digital Television: The Site(tm) (digitaltelevision.com).

Apart from reception quality, the main difference is that the European DVB standard is a lot more flexible in how it lets you configure the bandwidth and the error correction between different services running in the same 6 MHz channel multiplex.

The bandwidth is there, same as ASTC, to run an HDTV channel. Australia in particular is mandating HDTV content over DVB from its broadcasters. But what the broadcasters in Oz think will make the DVB standard really pay are the possibilities for datacasting over some of the bandwidth -- and there is a huge plus in being able to datacast to people on the move.

COFDM is a much more rugged standard for mobile reception -- remember that very cute thinkpad sized combined TV/data terminal/GSM phone from Nokia. Mobile reception is easy with COFDM, but not possible with 8-VSB; in fact it's hard enough with the ATSC standard even to get good static reception.

This article by Craig Birkmaier does a particularly good job comparing the two standards, and brings out the exciting possibilities for a combined mobile data/TV/phone system.

It really depends how bad the picture is that you see on analogue TV at the moment. If the major problem is 'ghosting', ie spurious extra images caused by multiple reflection paths off the mountains, COFDM is particularly good at sorting these out to achieve constructive interference between the different paths.

If the major problem is 'snow', a signal amplifier box can help, just like for analogue TV. But if there's too much snow, this will destroy the digital signal.

One other trick with COFDM is that the TV company can add additional transmitters on the same frequency to sort out reception blackspots. With analogue signals this would just cause particularly bad destructive interference, and would be a Bad Idea. But because COFMM can make the two signals interfere constructively, this opens the door to networks of transmitters all on the same frequency.

This article by Craig Birkmaier is very good on COFDM vs 8-VSB generally, and covers the possibility of Single Frequency Networks in a bit more detail.