HDTV FAQ
What is HDTV?
HDTV (High Definition Television) is an entirely new way of transmitting and receiving a television broadcast signal. HDTV is Digital TV that displays a wide screen image at 720P or 1080i quality. HDTV broadcasts transmit up to six times the information as the old analog TV system, delivering higher quality picture and sound. Current television pictures are made up of 525 interlaced lines scanned horizontally. HDTV pictures are created by 1080 interlaced or 720 progressive scan lines, containing up to 2 million pixels (small dots that create a cleaner, more detailed picture). Ordinary TV displays about 300,000 pixels.
What is the difference between Digital TV, HDTV, and SDTV?
Digital TV (DTV) is the umbrella term used to describe the new digital television system adopted by the FCC in December 1996. DTV in its broadest terms includes High Definition Television (HDTV), Standard Definition Television (SDTV), and a host of other potential applications. HDTV defines certain minimum performance attributes that deliver approximately twice the resolution of current TVs. SDTV refers to a system that provides a display resolution lower than that of HDTV.
What are the visible differences between HDTV and our present television system?
Your current TV set is probably almost square, with a 4-to-3 screen ratio. HDTV screens are about one-third wider than existing TV screens (16-to-9 ratio), which is more like the aspect ratio of a movie screen. Because of the added width, HDTV screens more easily match the peripheral vision range of the human eye, making it more natural to watch. Next, you will notice the pictures are clearer, crisper and more detailed, involving the viewer in an almost three-dimensional feeling. You can actually see details you missed while looking at them in real life. Complementing the amazing quality of the pictures is superb sound. With 5.1 channels of audio, HDTV delivers CD quality surround sound: front speakers on the right, center and left, along with two back speakers and a sub-woofer. Unlike HDTV, the present analog system signal suffers degradation as it travels from the antenna site. Viewers often see double images or "ghosting" and very poor picture quality. With high definition, the picture is always studio quality, whether the viewer's television set is located six miles or 60 miles from the antenna. Digital Television, including HDTV, received over the air is FREE.
Why should I buy an HDTV if there are no Digital signals in my area?
Today, approximately 50% of the total TV markets are receiving DTV signals. This will rapidly encompass virtually all TV markets over the next 2 years.
I heard that analog TV signals will be "shut down" in 2006, is this true?
2006 is a "target." In Washington, Democrats and Republicans want to balance the federal budget by the year 2004. Auctioning the analog spectrum has become a mantra for politicians as one method to help offset a portion of the budget deficits. In reality, few people really believe that DTV penetration by 2005 will allow the shutting-down of the analog signals by 2006. Federal legislation approved in 1997 allows for a continuation of the analog signal in markets where penetration of digital sets is less than 85 percent. Even though the budget is a politically explosive issue, broadcasters are committed to making huge investments to protect their existing franchises.
Can I get DTV over cable?
On February 23, 2000, The Consumer Electronics Association (CEA) and the National Cable Television Association (NCTA) reached voluntary agreements that detail the technical specifications that will enable consumers to receive DTV programming and services over cable systems. The technical ability to pass HDTV signals is important because networks that broadcast HDTV expect the full quality of their pictures to be retransmitted by cable operators. The cable operators will also provide carriage of the Program and System Information Protocol data, or PSIP, that allows for on-screen guides, including virtual channels, program name, descriptions, DTV format information, and content advisory information. This agreement is important for the future of DTV because two-thirds of Americans receive broadcast television programming via cable. However, the agreement does not mean that every digital signal broadcast by every station will be carried on cable. The "must carry" rules for the DTV signals that cable systems are required to carry are still being worked out.
What is Digital Cable?
Unlike over-the-air DTV, where the digital signals are superior to standard television signals, digital cable is simply a method of digitally compressing analog television so that the cable systems can offer more channels. Being digital also allows cable systems to offer two-way interactive capabilities, like E-Commerce, online videogames, and other data services. Broadcasters must follow the federally mandated ATSC digital television standards for quality and the broadcast signals are designed to be displayed on DTV sets. Cable systems can choose any digital standard they wish to save channel capacity and their signals are designed to be shown on traditional analog sets. Broadcasters must follow the federally mandated ATSC digital television standards for quality and the broadcast signals are designed to be displayed on DTV sets.
What cable channels offer High Definition programming?
ESPN, The Discovery Channel, HBO and New York's Madison Square Garden sports network have all committed to using HDTV. The satellite services DirecTV, and The Dish Network have also announced plans for their own HDTV channels. And with the recent technical agreement between the Consumer Electronics Association - CEA, and the National Cable Television Association - NCTA, more and more local DTV stations will begin appearing on cable systems in the near future.
What's the difference between digital cable and digital television?
It boils down to this: DTV means improved picture and sound. Digital Cable means more channels. Cable operators will need to find a balance between program choices and higher definition programming. name=18.0>18. Will it work with all my other video gear? Just like conventional televisions, digital TVs are sold with a wide variety of features. However, because manufacturers understand that people have many different video devices, most DTV sets have multiple inputs in order to accommodate multiple devices. They understand that VHS, DVD, cable, satellite, and broadcast DTV may all have to be displayed by a single DTV set. However, it's a good idea for consumers to know exactly what kinds of devices they want to connect so that they can make sure the DTV set they purchase has the type of connections they need.
What's the difference between Direct TV or the Dish Net and Digital Television?
Digital Television, including HDTV, received over the air is FREE. Like cable, Direct-to-Home satellite networks are not free. You pay a monthly subscription fee. DirecTV and The Dish Network are the nation's two leading Direct-to-Home satellite networks. Like cable, both package a variety of channels, including sports, movies, news, even local broadcast stations, and send them via a digital satellite signal to rooftop dish antennas on their subscriber's homes. Digital Television, on the other hand, is transmitted from TV towers, mirroring today's free broadcast model. Broadcasters must always provide a free signal; however, the ATSC standard allows them to develop additional over-the-air pay DTV services if they chose. DTV broadcasters must also follow the federally mandated ATSC digital television standards for quality and the broadcast signals are designed to be displayed on DTV sets. Satellite networks can chose any digital standard they wish and their signals are designed to be shown on traditional analog sets. However, both DirecTV and Dish have begun broadcasting some HDTV programs, and these programs do follow the ATSC standards and must be viewed on an HDTV set to enjoy the higher resolution picture.
Will my video tapes work?
Yes. Virtually all DTV sets have video and audio inputs for standard and S-video machines. In fact, digital sets, because of line doubling and other advanced display capabilities, often have the ability to significantly improve the picture quality of pre-recorded video tapes.
Will I be able to record the digital signal?
Right now, VHS is limited to the analog signals of conventional broadcasting or the signals from the NTSC video out on your DTV set, which have been converted to analog. So while you can't record the digital signals themselves yet, you can record a high quality analog signal coming out of your digital set. If this digital signal is HDTV, what you record on VHS will be letterboxed or altered in some way to fit the smaller dimensions of a conventional television.
Why are plasma TV monitors better?
Higher resolution Plasma display devices have higher resolution than conventional TV sets, and are capable of displaying full HDTV and DTV signals as well as XGA, SVGA and VGA signals from a computer. For example, you can get plasma displays with a 1024 x 1024 pixel high-resolution that can display images at true 1080i and 720p HDTV resolution, as well as 480i and 480p HD signals. No scan lines Conventional CRTs use an electron beam to scan the picture tube from top to bottom at regular intervals, lighting the phosphors to create the image. In the case of standard (NTSC) TV, visible scan lines can be seen. Most plasma displays include built-in line doubling to further improve image quality when viewing standard analog video sources such as TV broadcasts and VCR tapes. Exceptional color accuracy High-end plasma displays are capable of displaying 16.77 million colors -- providing superb color realism with exceptionally subtle gradations between colors. Widescreen aspect ratio Plasma display devices have a widescreen 16:9 aspect ratio, the relationship between the screen's width and height. This is the proper aspect ratio for HDTV, and also allows many DVD-Video movies to be viewed in widescreen format, as originally seen in the theater. Perfectly flat screen Plasma display monitors have screens that are perfectly flat, with no curvature whatsoever. This eliminates the edge distortion that can occur in CRT displays. Uniform screen brightness Unlike some rear and front projection televisions that suffer from uneven screen brightness -- seen as "hot spots" in the middle of the screen or a darkening near the edges and especially corners -- plasma displays illuminate all pixels evenly across the screen. Slim, space-saving design Plasma display monitors are only a few inches thin-providing installation options never before possible. In addition to stand mounting, they can be hung on a wall or from a ceiling, allowing you to enjoy big-screen home theater impact from a component that doesn't dominate floor space. Conventional TVs and front projectors, by comparison take up far more real estate and are much more limited in placement flexibility. Plasma monitors have an elegant, understated "picture frame" appearance that blends inconspicuously with any decor; with a chassis not much wider than the display screen itself. Because they eliminate the need for a front projection unit and a projection screen, plasma display monitors are also ideal for use in a wide variety of business and commercial applications where the use of a front projector would not be feasible. Wide viewing angle Plasma displays offer a viewing angle of 160 degrees (top to bottom and left to right) -- much better than rear projection TVs and LCD displays. This allows a larger number of viewers to enjoy proper image reproduction from a wider variety of locations throughout the room. Universal display capability Most plasma monitors can accept any video format formats. Typically, they will include composite video (NTSC, PAL SECAM) (standard RCA jacks), S-video and component video inputs, plus one or more RGB inputs to accept the video output from a computer. Whether you want to view a sporting event on HDTV, a DVD-Video movie, a satellite broadcast or even surf the Internet with incredible big screen impact, chances are a plasma monitor will accommodate your needs. Immunity from magnetic fields Because plasma displays do not use electron beams, as conventional CRT displays do, they are immune to the effects of magnetic fields. Components such as loudspeakers that contain strong magnets can distort the picture if placed too close a standard TV (which has a CRT). On the other hand, plasma displays can be placed in close proximity to any type of loudspeaker and not experience image distortion.
What are my options for sound with a plasma TV?
There is only one plasma TV maker that incorporates built in speakers into the plasma frame (Philips). Most manufacturers do however offer speakers as additional options which can be attached to the side of the plasma TV. Amplification of these speakers comes through built in 7 or 8 watt amplifiers which are built in to the side of the plasma display (this is plenty of wattage for excellent audio output). Many users will want to attach speakers to the amplifiers for watching simple programming such as the news or displaying the unit in a board room or at a trade show. There are two options to consider here: The user may purchase flat, slim speakers which attach to the sides of the plasma monitor The viewer may choose to use his or her own bookshelf, or satellite speakers. Small cube type speakers may also be attractively mounted on the wall beside the plasma display TV. In addition, home users will often use a sound system with surround sound or their external amplifier/receiver component. Some manufacturers of plasma TVs offer no built in amplifiers for sound. In this instance an outboard amplifier/receiver must be used.
How do plasma TVs work?
Plasma TVs use thousands of sealed, low pressure glass chambers filled with a mixture of neon and xenon. Behind these chambers are colored phosphors, one red, one blue, and one green for each chamber. When energized, these chambers of "plasma" emit invisible UV light. The UV light strikes the red, green and blue phosphors on the back glass of the display making them produce visible light.
When are plasma TVs used?
Home Theater A plasma TV is idea for the home theater enthusiants who want the best possible picture whilist saving space. Network Control Rooms Data and video can be displayed with equal quality and clarity, allow control room or network managers to constantly view the performance of their network. Meeting Rooms Make your meeting room PC friendly. Executive Offices The high tech look will be sure to impress customers, while serving the dual purpose of making your executives more effective during meetings and presentations. Corporate Lobbies Plasma is the ultimate high tech tool to display your company's products, services, or events in a visually appealing technology. Unlike light boxes, which require static duratrans, these flat displays can show presentations or live video, making for a more informative and effective method of communicating with customers. You are practically guaranteed to gain their undivided attention. Updateable Signage Plasma's wide viewing angles thin profile and high brightness has allowed for the concept of digital signs that can be hung throughout offices, stores, shopping malls, or anywhere you want to share pertinent video or data to your employees or customers. Touch Screens Apply a touch screen to a plasma and you have a dynamic interactive digital work board. Light Weight Plasmas Can be mounted on a rolling stand and shared between several meeting rooms or offices. Video Conferencing Many companies use projectors with video conferencing. Projectors require dark rooms to produce vibrant images. Video conferencing cameras require bright rooms to pick up images. These two technologies contradict each other. Because of its performance in ambient light, plasma is the ideal display system for video conferencing.
What is the plasma in plasma TVs?
An electrically neutral, highly ionized substance composed of ions, electrons, and neutral particles. Plasma contains almost equal numbers of free electrons and positive ions. In a plasma the electrons have been stripped away from the central nucleus. Therefore, a plasma consists of a sea of ions and electrons and is a very good conductor of electricity and is affected by magnetic fields. Electrons are separated from their respective nucleus when enough heat is applied.
How far away from the plasma should I be?
Pixel distortion or motion artifacts can occur on early generation plasma monitors when displaying an incoming signal with poor resolution (some cable channels - a signal of around 250 interlaced is generally poor). However, this "pixelating" effect is lessened by increasing viewing distance from the plasma display. With early generation models I generally viewed the proper distances as 8 to 12 feet on a 42" plasma TV and 12 to 16 feet or more on a 50" plasma. Now, with the many improvements that have been made to the units, the latest 50" models can be viewed comfortably from 9 feet. So it really becomes a matter of preference. I view a 42" plasma from feet in my own home and it looks superb.
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