Digital television in the United States
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In the United States, digital television may be received via cable television, satellite television, or via free-to-air terrestrial television. Full-power analog television broadcasts are required by federal law to cease by February 17, 2009. "Low-power", "Class A", and "TV Translator" stations are not currently required to cease broadcasts. Terrestrial and cable systems must use ATSC standards.[1]
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[edit] Digital transmission standards
Currently, there are four main varieties of digital television, as defined by the ATSC standards used by the US. These include:
- Standard definition - 480i, to maintain compatibility with existing NTSC sets
- Enhanced definition - 480p, about the same quality as current DVDs
- High definition - 720p or 1080i or 1080p
A digital television set (as sold in the U.S.) usually uses a 16:9 aspect ratio display with an integrated ATSC tuner. Lower-resolution sources like regular DVDs may be upscaled to the native resolution of the TV. Most television broadcasts, as of 2007, are in standard definition, but there are an increasing number of high-definition channels and special events.
In North America, FOX, MyNetworkTV (both owned by the News Corporation), ABC, and ESPN (ABC and ESPN are both owned by Disney) currently broadcast 720p content. NBC, Universal HD (both owned by the NBC Universal subsidiary of General Electric and Vivendi), CBS, The CW (co-owned by CBS and Time Warner), HBO (owned by Time Warner), Showtime (owned by CBS), Starz!, MOJO HD, HDNet ,TNT (owned by Time Warner), CNN (also owned by Time Warner), and Discovery HD Theater currently broadcast 1080i content. In Canada, virtually all over-the-air HD stations broadcast 1080i, as do most cable specialty channels. For list of local over the air HD channels visit
[edit] Cable and satellite
Currently, most Americans get their digital television via cable or satellite. By law, digital cable television uses the same ATSC standard, though with a different modulation (QAM instead of 8-VSB). Digital television sets are able to view the baseline set of unencrypted programming, known as basic cable. By FCC regulation, the remaining encrypted channels must be viewable with a receiver equipped with a CableCARD, in theory eliminating the need for any proprietary set-top box.
[edit] Terrestrial
It is estimated that as of April 2007, 28% of American households have an HDTV set, a total of 35 million sets, and that 86% of owners are highly satisfied with the HDTV they are getting.[2] It is estimated that by the end of 2010, 59% of American TVs will be HDTVs.[citation needed] All TV stations currently broadcast in both digital and analog and major networks broadcast in HD in most markets.
While many in the industry wanted a flexible or delayed deadline, FCC attempted to force the issue (at the behest of Congress, which wants to reclaim the spectrum for emergency services, as well as to conduct the auction of frequencies 76-88 MHz and old analog channels 60 to 69, as well channels 52 to 59 in the near future), by mandating DTV tuners be phased in to all new TV sets, beginning with the largest.[citation needed] Many dates were proposed, but Congress finally fixed February 17, 2009, in law as the maximum end date for analog television authorizations.[3] Because this date comes after the NCAA's Bowl Championship Series and the NFL's Super Bowl XLIII, there will be less of a chance of an acute hardware shortage from people waiting until the last minute to purchase an ATSC tuner than there would have been with a January 1 cutoff.[citation needed] The original deadline of January 1, 2006 was abolished when it was realized that TV stations and customers would not be able to meet the earlier deadline.[citation needed]
[edit] Early rollout
On May 8, 2008, FCC Chairman Kevin J. Martin announced that the agency will test run the transition to digital television in Wilmington, North Carolina beginning September 8, 2008. This is in order to work out any problems which may occur before most of the country's broadcasters stop transmitting traditional analog signals and upgrade to digital-only broadcasting.
[edit] References
- ^ FCC. The Digital TV Transition FAQs.
- ^ WKYC's Director's Cut with Frank Macek: News: HDTV Penetration at 28%
- ^ 47 USC 309(j)(14)(A) [1] as amended by section 3002 of S.1932 signed into law February 8, 2006
[edit] See also
- CECB - Coupon-Eligible Converter Box
- High-definition television in the United States
[edit] External links
- "The Digital TV Transition: What You Need to Know About DTV" (FCC)
- DTV Transition (DTV Transition Coalition)
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