Digital Television

Digital Television (DTV) is a new broadcasting technology that will transform your television viewing experience. DTV enables broadcasters to offer television with movie-quality picture and sound. It can also offer multiple programming choices, called multicasting, and interactive capabilities. Converting to DTV also will free up parts of the scarce and valuable broadcast spectrum. Those portions of the spectrum can then be used for other important services, such as public and safety services (police and fire departments, emergency rescue), and advanced wireless services. The Transition to Digital TV TV stations serving all markets in the United States are airing digital television programming today, although most will continue to provide analog programming through February 17, 2009. At that point, full-power TV stations will cease broadcasting on their current analog channels, and the spectrum they use for analog broadcasting will be reclaimed and put to other uses. The Commission's digital tuner rule specifies that as of March 1, 2007, all new TVs must include digital tuners. This rule prohibits the manufacture, import, or interstate shipment of any device containing an analog tuner, unless it also contains a digital tuner. Despite this prohibition on manufacture and shipment, retailers may continue to sell analog-only devices from existing inventory. As a result, at the point of sale, many consumers may not be aware that this equipment will not be able to receive over-the-air-television signals after February 17, 2009. To address this issue, the FCC has adopted a rule requiring sellers to display the following text if they are selling TV equipment with only an analog broadcast tuner: Consumer Alert This television receiver has only an analog broadcast tuner and will require a converter box after February 17, 2009, to receive over-the-air broadcasts with an antenna because of the Nation’s transition to digital broadcasting. Analog-only TVs should continue to work as before with cable and satellite TV services, gaming consoles, VCRs, DVD players, and similar products. For more information, call the Federal Communications Commission at 1-888-225-5322 (TTY: 1-888-835-5322) or visit the Commission’s digital television website at: www.dtv.gov. Analog TVs Will Need Additional Equipment to Receive Over-the-air Television When the DTV Transition Ends Consumers who rely on antennas (including outside antennas and "rabbit ears") to receive broadcast signals on TV sets having only analog tuners will need to obtain separate digital-to-analog set-top converter boxes to watch over-the-air TV. These boxes receive digital signals and convert them into analog format for display on analog TVs. Analog sets connected to such converter boxes will display digital broadcasts, but not necessarily in the full, original digital quality. Converter Box Coupon Program Beginning in 2008, your household may be able to obtain up to two coupons worth $40 each toward the purchase of converter boxes. The National Telecommunications and Information Administration (NTIA) has responsibility for administering the coupon program, and will issue rules regarding the coupons in the future. Additional information can be found at www.ntia.doc.gov/otiahome/dtv/dtvcoupon.html. Cable and Satellite TV Cable subscribers may need new DTV equipment to view DTV programming in digital format. You should ask your cable provider what you will need and when. Satellite subscribers may need new DTV equipment to receive and view high definition digital programming. You should ask your satellite company what you will need and when. Digital television Quality Levels There are many quality levels of digital television programming. The most common are: · Standard Definition TV (SDTV) - SDTV is the basic level of quality display and resolution for both analog and digital. Transmission of SDTV may be in either the traditional (4:3) or widescreen (16:9) format. · Enhanced Definition TV (EDTV) - EDTV is a step up from Analog Television. EDTV comes in 480p widescreen (16:9) or traditional (4:3) format and provides better picture quality than SDTV, but not as high as HDTV. · High Definition TV (HDTV) - HDTV in widescreen format (16:9) provides the highest resolution and picture quality of all digital broadcast formats. Combined with digitally enhanced sound technology, HDTV sets new standards for sound and picture quality in television. (Note: HDTV and digital TV are not the same thing -- HDTV is one format of digital TV.) Digital Television Facts At A Glance Analog DTV HDTV · Date for final transition to digital is February 17, 2009. After that date, stations will only broadcast digital signals. · Consumers will always be able to connect an inexpensive receiver, a set top box, to their existing analog TV to decode DTV broadcast signals. · Set top boxes will not convert your analog TV to high-definition. · Analog TVs will continue to work with cable, satellite, VCRs, DVD players, camcorders, video games consoles and other devices for many years. · Digital cable or digital satellite does not mean a program is in high-definition. · Digital pictures will be free from the "ghosts" and "snow" that can affect analog transmissions. · Multicasting is available. · HDTV is available. · Data streaming is available. · High-definition broadcasts offered. · Best available picture resolution, clarity and color. · Dolby theatre surround-sound. · Dolby surround-sound. · Wide screen "movie-like" format

Source: DTVinfo@fcc.gov

What is the Difference Between an LCD TV and a Plasma TV?

A. Outward appearances are definitely deceiving when it comes to LCD and Plasma televisions. Although both types of televisions are flat and thin, they employ different technology in an attempt to deliver similar results.

Plasma TV Overview

Plasma television technology is based loosely on the fluorescent light bulb. The display itself consists of cells. Within each cell two glass panels are separated by a narrow gap in which neon-xenon gas is injected and sealed in plasma form during the manufacturing process. The gas is electrically charged at specific intervals when the Plasma set is in use. The charged gas then strikes red, green, and blue phosphors, thus creating a television image. Each group of red, green, and blue phosphors is called a pixel (picture element).

Although Plasma television technology eliminate the need for the bulky picture tube and electron beam scanning of traditional televisions, because it still employs the burning of phosphors to generate an image, Plasma televisions still suffer from some of the drawbacks of traditional televisions, such as heat generation and screen-burn of static images.

LCD TV Overview

LCD televisions, on the other hand, use a different technology (see also question #1 for this same explanation).

Basically, LCD panels are made of two layers of transparent material, which are polarized, and are "glued" together. One of the layers is coated with a special polymer that holds the individual liquid crystals. Current is then passed through individual crystals, which allow the crystals to pass or block light to create images. LCD crystals do not produce their own light, so an external light source, such as florescent bulb is needed for the image created by the LCD to become visible to the viewer.

Unlike standard CRT and Plasma televisions, since there are no phosphors that light up, less power is need for operation and the light source in an LCD television generates less heat than a Plasma or traditional television. Also, because of the nature of LCD technology, there is no radiation emitted from the screen itself.

Plasma vs LCD

The ADVANTAGES of Plasma over LCD are:

1. Larger screen size availability.

2. Better contrast ratio and ability to render deeper blacks.

3. Better color accuracy and saturation.

4. Better motion tracking (little or no motion lag in fast moving images).

The DISADVANTAGES of Plasma vs LCD include:

1. Plasma TVs are more susceptible to burn-in of static images.

2. Plasma TVs generate more heat than LCDs, due to the need to light of phosphors to create the images.

3. Does not perform as well at higher altitudes.

4. Shorter display life span (about 30,000 hours or 8 hrs of viewing a day for 9 years) than LCD. However,

screen life span is improving to as high as 60,000 hours. due to technology improvements.

LCD television ADVANTAGES over Plasma include:

1. No burn-in of static images.

2. Cooler running temperature.

3. No high altitude use issues.

4. Increased image brightness over Plasma.

5. Longer display life (about 60,000 hours - at which time all you may need to do is replace the light source,

not the entire set). This can vary according other environmental and use factors.

6. Lighter weight (when comparing same screen sizes) than Plasma counterparts.

DISADVANTAGES of LCD vs Plasma televisions include:

1. Lower contrast ratio, not as good rendering deep blacks.

2. Not as good at tracking motion (fast moving objects may exhibit lag artifacts) - However, this is improving.

3. Not as common in large screen sizes above 42-inches as Plasma. However, the number is growing fast,

with some LCD sets having a screen size as large as 65-inches now available to the general public.

4. Although LCD televisions do not suffer from burn-in susceptibility, it is possible that individual pixels on an

LCD televisions can burn out, causing small, visible, black or white dots to appear on screen individual

pixel cannot be repaired, the whole screen need to be replaced at that point, if the individual pixel

burnout becomes annoying to you.

5. LCD televisions are typically more expensive than equivalent-sized Plasma televisions (although this is

changing), especially when comparing EDTV Plasmas to HDTV-LCD Televisions.

©2007 About, Inc., A part of The New York Times Company. All rights reserved

By: Robert Silva

Confusion over high-definition TV

Now that a critical mass of people have embraced digital TV, DVDs, and digital video recorders, the next revolution for TV is being prepared for our sets. In most corners of TV and technology industries, high-definition (HDTV) is being heralded as the biggest thing to happen to the television since colour. HD essentially makes TV picture quality at least four times better than now. But there is real concern that people are not getting the right information about HD on the High Street. Thousands of flat panel screens - LCDs (liquid crystal displays), plasma screens, and DLP rear-projection TV sets - have already been sold as "HD", but are in fact not able to display HD. No connectors "The UK is the largest display market in Europe," according to John Binks, director of GfK, which monitors global consumer markets. But, he added: "Of all the flat panel screens sold, just 1.3% in the UK are capable of getting high-definition." There are 74 different devices that are being sold as HD but are not HD-ready, according to Alexander Oudendijk, senior vice president of marketing for satellite giant Astra. They may be fantastic quality TVs, but many do not have adaptors in them - called DVI or HDMI (High-Definition Multimedia Interface) connectors - which let the set handle the higher resolution digital images. Part of this is down to lack of understanding and training on the High Street, say industry experts, who gathered at Bafta in London for the 2nd European HDTV Summit last week. "We have to be careful about consumer confusion. There is a massive education process to go through," said Mr Binks. The industry already recognised that it would be a challenge to get the right information about it across to those of us who will be watching it. Eventually, that will be everyone. The BBC is currently developing plans to produce all its TV output to meet HDTV standards by 2010. Preparations for the analogue switch-off are already underway in some areas, and programmes are being filmed with HD cameras. BSkyB plans to ship its first generation set-top boxes, to receive HDTV broadcasts, in time for Christmas. Like its Sky+ boxes, they will also be personal video recorders (PVRs). The company will start broadcasts of HDTV programmes, offering them as "premium channel packages", concentrating, to start with, on sports, big events, and films, in early 2006. But the set-top box which receives HDTV broadcasts has to plug into a display - TV set - that can show the images at the much higher resolution that HD demands, if HDTV is to be "real". By 2010, 20% of homes in the UK will have some sort of TV set or display that can show HD in its full glory. Education, education, education But it is all getting rather confusing for people who have only just taken to "being digital". As a result, all the key players, those who make flat panel displays, as well as the satellite companies and broadcasters, formed a HD forum in 2004 to make sure they were all talking to each other. Part of the forum has been concerned with issues like industry standards and content protection. But it has also been preoccupied with how to help the paying public know exactly what they are paying for. From next month, all devices that have the right connectors and resolution required will carry a "HD-Ready" sticker. This also means they are equipped to cope with both analogue and HDTV signals, and so comply with the minimum specification set out by the industry. "The logo is absolutely the way forward," said David Mercer, analysts with Strategy Analytics. "But it is still not appearing on many retail products." The industry is upbeat that the sticker will help, but it is only a start. "We can only do so much with the position we are in today with manufacturers," said Mr Oudendijk. "There may well be a number of dissatisfied customers in the next few months." The European Broadcast Union (EBU) is testing different flavours of HD formats to prepare for even better HDTV further down the line. It is similarly concerned that people get the right information on HDTV formats, as well as which devices will support the formats. "We believe consumers buying expensive displays need to ensure their investment is worthwhile," said Phil Laven, technical director for the EBU. The TV display manufacturers want us to watch HD on screens that are at least 42in (106cm), to get the "true impact" of HD, they say, although smaller displays suffice. What may convince people to spend money on HD-ready devices is the falling prices, which continue to tumble across Europe. The prices are dropping an average of 20% every year, according to analysts. LCD prices dropped by 43% in Europe as a whole last year, according to Mr Oudendijk.

By Jo Twist
BBC News science and technology reporter

What is the Difference Between Digital TV and Analog TV? The difference between Analog TV and Digital TV boils down to the way the TV signal is transmitted. Standard analog TV is transmitted in a manner similar to radio. In fact, the video signal of analog television is transmitted in AM, while the audio is transmitted in FM. Analog TV is subject to interference, such as ghosting and snow, depending on the distance and geographical location of the TV receiving the signal. In addition, the amount of bandwidth assigned to an analog TV channel restricts the resolution and overall quality of the image. The current analog TV signal standard (in the U.S.) is referred to as NTSC. NTSC is the U.S. standard that was adopted and came into popular use after World War II. NTSC is based on a 525-line, 60 fields/30 frames-per-second at 60Hz system for transmission and display of video images. This is an interlaced system in which each frame is scanned in two fields of 262 lines, which is then combined to display a frame of video with 525 scan lines. This system works, but one drawback is that color TV broadcasting was not part of the equation when the system was approved. The implementation of color into the NTSC format has been a weakness of the system, thus the term for NTSC became known by many professionals as "Never Twice The Same Color". Ever notice that color quality and consistency varies quite a bit between stations? Digital TV, or DTV, on the other hand, is transmitted as data bits of information, just as computer data is written or the way music is written on a CD. In this way, the signal is basically "on" or "off". In other words, the intent of DTV technology is that the viewer either sees an image or nothing at all. There is no gradual signal loss as distance from the transmitter increases. If the viewer is too far from the transmitter or is in an undesirable location, there is nothing to see. On the other hand, unlike analog TV, digital TV has been designed from the ground up to take all the main factors of the television signal into consideration: B/W, color, and audio and can be transmitted as an interlaced (lines scanned in alternate fields) or progressive (lines scanned in linear sequence) signal. As a result, there is greater integrity and flexibility of signal content. In addition, since the DTV signal is made up of "bits", the same bandwidth size that takes up a current analog TV signal, can accommodate not only a higher quality image in digital form, but the extra space not used for the TV signal can be used for additional video, audio, and text signals. In other words, broadcasters can supply more features, such as surround sound, multiple language audio, text services, and more in the same space now occupied by a standard analog TV signal. However, there is one more advantage to the ability of a Digital TV channel's space; the ability to transmit a High Definition (HDTV) signal. Lastly, another difference between Digital TV and Analog TV is the ability to broadcast programming in a true widescreen (16x9) format. The shape of the picture more closely resembles the shape of a movie screen, which enables the viewer to see the movie as the filmmaker intendt more of the action in one camera shot, such as viewing the entire length of a football field without making look like it is a long distance away from the camera. A 16x9 TV can display widescreen images without a large amount of picture space taken up by black bars on the top and bottom of a widescreen image, which is what you see if such images are shown on a standard TV. Even non-HDTV sources, such as DVD can also take advantage of a 16x9 TV.

By: Robert Silva

©2007 About, Inc., A part of The New York Times Company. All rights reserved.

By February 17, 2009, all analog television broadcasts are scheduled to be turned off There are a growing number of programs to watch in HDTV. All of the major networks: ABC, NBC, CBS, CW, and PBS broadcast a growing portion of their schedules in HDTV. In addition, FOX previously broadcast much of their programming in 480p (standard definition digital TV), but came on board with 720p broadcasting in the FALL of 2004. Here is a list of TV stations broadcasting in DTV or HDTV. If your favorite local station is not on the list, give them a call to find out their current status with regards to DTV or HDTV. In addition, Discovery, Showtime, HBO, HDnet, TNT, ESPN, and FOX Sports, have HDTV signal feeds. As a result, a growing number of cable systems around the country are now providing HDTV cable service, including systems owned by COX, Comcast, Cablevision, and Time Warner (Check with your local cable company for service in your area). Even local stations are getting onboard with an increasing number broadcasting their local news programs in high definition. Lastly, the two main satellite service providers, DirecTV and DishNetwork offer HDTV channels as well. Here is a comprehensive daily listing of what is being shown in HDTV. However, although there is quite of bit of programming available in HDTV, currently accessing the programming can be frustrating for the consumer. For example, local HDTV broadcasts are available over-the-air via antenna, but your local cable outlet may not be passing all those signals through your cable system. In addition, although Satellite offers the most HDTV programming (via sport channels and movie channels), they may not offer much in the way of local or network HDTV programming. Then, there is the issue of pricing. Some cable systems offer some basic HDTV services for no extra charge, but most offer an HDTV tier of local channels and movie channels for an extra fee, but some often charge extra on top of that for services such as ESPN-HD and Discovery-HD. HDTV is still going through a lot of growing pains, partly caused by government policies and partly caused by programming providers. There definitely needs to be some consistency offerings, pricing, and more strict timetables -- but be patient -- HDTV can currently be accessed via over 1200 television stations and most cable systems in the major markets. This trend will surely continue as more consumers buy HDTVs and demand better access to programming. Of course, by February 17, 2009, all analog television broadcasts are scheduled to be turned off, so all televisions stations need to be onboard by that time.

By: Robert Silva

©2007 About, Inc., A part of The New York Times Company. All rights reserved.