What's the Deal with Digital?
If you've seen digital TV, you probably want one and that's a common reaction. But, how do you decide which one to get? After all, the prospect of buying something you don't understand is rather daunting. Like all new technology, digital TV has spawned some new terminology — a basic understanding of which is important to help you make an educated buying decision. If you've looked around, then you know that there has been no standard language for labeling digital sets. The very same TV has likely been touted differently by different retailers, making comparison shopping a nightmare. The reason for this is simple: The industry hadn't decided on standard language to use, so merchants and advertising types were on their own to decide how to describe this new technology to consumers. To remedy the situation, the Consumer Electronics Association (CEA) recently released the following new terminology for labeling digital.

High-Definition Television (HDTV)
This is a fully integrated television receiver that will receive all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats; will display active vertical scanning lines of 720 progressive (720p), 1080 interlaced (1080i), or higher in a 16:9 widescreen aspect ratio. It must also receive and decode, or pass-through for decoding, Dolby Digital audio.

High-Definition Television (HDTV) Monitor
This is a monitor (presumably ATSC tunerless) that will present active vertical scanning lines to meet the 720 progressive (720p), 1080 interlaced (1080i) or higher formats. It must be capable of displaying a 16:9 image at the specified vertical resolution of 540p, 810i or higher to meet the definition of HDTV.

High-Definition Television (HDTV) Tuner
This is an RF receiver that will receive all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. It must output the ATSC Table 3 HDTV formats of 720p or 1080i/p with minimum active vertical scanning lines of 720p, 1080i or higher. Additionally, it may output HDTV formats converted to other formats. The lower-resolution ATSC Table 3 formats can be output at lower resolution levels. Alternatively, the output can be a digital bitstream with the full resolution of the broadcast signal. It must receive and decode, or pass-through for decoding, Dolby Digital audio.

Enhanced-Definition Television (EDTV)
This is a fully integrated television receiver that receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. It must have active vertical scanning lines to meet the 480 progressive (480p) format or higher, but does not specify any particular aspect ratio. It must receive and decode, or pass-through for decoding, Dolby Digital audio.

Enhanced-Definition Television (EDTV) Monitor
This is a monitor (presumably ATSC tunerless) that has active vertical scanning lines to meet the 480 progressive (480p) format or higher, but does not specify a picture aspect ratio.

Enhanced-Definition Television (EDTV) Tuner
This is an RF receiver that receives all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. It must output the ATSC Table 3 HDTV formats of 720p or 1080i/p with minimum active vertical scanning lines of 480p. Alternatively, the output can be a digital bitstream output capable of transporting 480p, while the ATSC Table 3 480i format can be output at 480i. It must receive and decode, or pass-through for decoding, Dolby Digital audio.

Standard-Definition Television (SDTV)
This now refers to a fully integrated television receiver that receives all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats to "produce a useable picture." It can have active vertical scanning lines less than EDTV quality. No aspect ratio is specified, and it must receive some form of useable audio signal.

Standard-Definition Television (SDTV) Tuner
This is an RF receiver that receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. Output may be in the form of NTSC signals. It must receive, decode or pass-through for decoding Dolby Digital audio.

First of all, what does ATSC mean? This stands for Advanced Television Systems Committee — the people who put together the standards for the new digital system. ATSC terrestrial broadcasts are over-the-air digital broadcasts, the kind you pick up with an antenna. The digital cable providers are still hammering out the details on their conversion to ATSC. The Table 3 signals referred to in the new standards are the 18 approved digital formats.

The new system differentiates between televisions (those having a digital tuner and converter box built in), monitors (which require an additional set-top box to utilize digital broadcasts), and tuners (a device that translates the digital broadcast into something a monitor can use). It's important to note that while a converter is needed to watch digital broadcasts on a monitor, most have integrated NTSC (normal TV) tuners for analog TV signals. So even if you don't have a set-top box, you can always watch regular TV and DVD on them, with amazing results.

Another place for confusion is the difference between interlaced and progressive scan. An interlaced signal alternates scan lines by refreshing them en mass in two groups. To change its picture, a set displaying an interlaced signal starts at the very top scan line (running horizontally across the top of the screen) and goes to the bottom of the screen, labeling every other line as even, odd, even, odd& you get the picture. Every 1/60th of a second, half of the lines at a time are switched out — first all of the evens, then all of the odds. If you are comparing an interlaced picture with another interlaced picture, the higher the number, the better the picture (1080i is better than 480i for example). Simple, right? Well, here is the part where comparisons get a little tricky.

The alternative to interlaced is a progressive-scan system. In this system, the display lines are not switched out in two big groups, but rather one at a time, in a sequence that goes from the top of the screen to the bottom. Again, the higher the number, the better the picture (720p is better than 480p for example).

Because these systems work so differently, comparing TVs that use different systems is (forgive the cliche) like comparing apples to oranges. Some people prefer an interlaced TV with a lot of scan lines, while others think a progressive scan TV with less lines looks equally as good. It is a matter of personal preference, but it's also determined by what type of programming you watch. High-action items such as sporting events tend to look better in a progressive-scan format, while movies without a lot of change in the background look better in an interlaced format.

The other term that gets thrown around a lot is aspect ratio. This refers to the proportion of screen width to screen height. Televisions come in two aspect ratios. The first is 4:3. This is the screen shape you probably think of when you imagine a TV. The second is 16:9. This is a panoramic view much like that of a movie theater screen. Many 4:3 aspect ratio TVs have a mode that allows them to emulate the appearance of 16:9 TVs by adding a black bar to the top and bottom of the picture. If you've ever watched a letterboxed edition of a VHS or DVD movie, you know what this looks like. Which is better for you? If you're mainly going to watch movies, then the 16:9 aspect ratio sets are definitely worth the additional cost. If your focus is broadcast TV and sports, a 4:3 set will probably be fine. In the future, broadcasters are expected to begin using the 16:9 ratio for TV programming and sports, but currently very few do.

What's the Deal with Digital?
If you've seen digital TV, you probably want one and that's a common reaction. But, how do you decide which one to get? After all, the prospect of buying something you don't understand is rather daunting. Like all new technology, digital TV has spawned some new terminology — a basic understanding of which is important to help you make an educated buying decision. If you've looked around, then you know that there has been no standard language for labeling digital sets. The very same TV has likely been touted differently by different retailers, making comparison shopping a nightmare. The reason for this is simple: The industry hadn't decided on standard language to use, so merchants and advertising types were on their own to decide how to describe this new technology to consumers. To remedy the situation, the Consumer Electronics Association (CEA) recently released the following new terminology for labeling digital.

High-Definition Television (HDTV)
This is a fully integrated television receiver that will receive all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats; will display active vertical scanning lines of 720 progressive (720p), 1080 interlaced (1080i), or higher in a 16:9 widescreen aspect ratio. It must also receive and decode, or pass-through for decoding, Dolby Digital audio.

High-Definition Television (HDTV) Monitor
This is a monitor (presumably ATSC tunerless) that will present active vertical scanning lines to meet the 720 progressive (720p), 1080 interlaced (1080i) or higher formats. It must be capable of displaying a 16:9 image at the specified vertical resolution of 540p, 810i or higher to meet the definition of HDTV.

High-Definition Television (HDTV) Tuner
This is an RF receiver that will receive all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. It must output the ATSC Table 3 HDTV formats of 720p or 1080i/p with minimum active vertical scanning lines of 720p, 1080i or higher. Additionally, it may output HDTV formats converted to other formats. The lower-resolution ATSC Table 3 formats can be output at lower resolution levels. Alternatively, the output can be a digital bitstream with the full resolution of the broadcast signal. It must receive and decode, or pass-through for decoding, Dolby Digital audio.

Enhanced-Definition Television (EDTV)
This is a fully integrated television receiver that receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. It must have active vertical scanning lines to meet the 480 progressive (480p) format or higher, but does not specify any particular aspect ratio. It must receive and decode, or pass-through for decoding, Dolby Digital audio.

Enhanced-Definition Television (EDTV) Monitor
This is a monitor (presumably ATSC tunerless) that has active vertical scanning lines to meet the 480 progressive (480p) format or higher, but does not specify a picture aspect ratio.

Enhanced-Definition Television (EDTV) Tuner
This is an RF receiver that receives all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. It must output the ATSC Table 3 HDTV formats of 720p or 1080i/p with minimum active vertical scanning lines of 480p. Alternatively, the output can be a digital bitstream output capable of transporting 480p, while the ATSC Table 3 480i format can be output at 480i. It must receive and decode, or pass-through for decoding, Dolby Digital audio.

Standard-Definition Television (SDTV)
This now refers to a fully integrated television receiver that receives all ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats to "produce a useable picture." It can have active vertical scanning lines less than EDTV quality. No aspect ratio is specified, and it must receive some form of useable audio signal.

Standard-Definition Television (SDTV) Tuner
This is an RF receiver that receives ATSC terrestrial digital transmissions and decodes all ATSC Table 3 video formats. Output may be in the form of NTSC signals. It must receive, decode or pass-through for decoding Dolby Digital audio.

First of all, what does ATSC mean? This stands for Advanced Television Systems Committee — the people who put together the standards for the new digital system. ATSC terrestrial broadcasts are over-the-air digital broadcasts, the kind you pick up with an antenna. The digital cable providers are still hammering out the details on their conversion to ATSC. The Table 3 signals referred to in the new standards are the 18 approved digital formats.

The new system differentiates between televisions (those having a digital tuner and converter box built in), monitors (which require an additional set-top box to utilize digital broadcasts), and tuners (a device that translates the digital broadcast into something a monitor can use). It's important to note that while a converter is needed to watch digital broadcasts on a monitor, most have integrated NTSC (normal TV) tuners for analog TV signals. So even if you don't have a set-top box, you can always watch regular TV and DVD on them, with amazing results.

Another place for confusion is the difference between interlaced and progressive scan. An interlaced signal alternates scan lines by refreshing them en mass in two groups. To change its picture, a set displaying an interlaced signal starts at the very top scan line (running horizontally across the top of the screen) and goes to the bottom of the screen, labeling every other line as even, odd, even, odd& you get the picture. Every 1/60th of a second, half of the lines at a time are switched out — first all of the evens, then all of the odds. If you are comparing an interlaced picture with another interlaced picture, the higher the number, the better the picture (1080i is better than 480i for example). Simple, right? Well, here is the part where comparisons get a little tricky.

The alternative to interlaced is a progressive-scan system. In this system, the display lines are not switched out in two big groups, but rather one at a time, in a sequence that goes from the top of the screen to the bottom. Again, the higher the number, the better the picture (720p is better than 480p for example).

Because these systems work so differently, comparing TVs that use different systems is (forgive the cliche) like comparing apples to oranges. Some people prefer an interlaced TV with a lot of scan lines, while others think a progressive scan TV with less lines looks equally as good. It is a matter of personal preference, but it's also determined by what type of programming you watch. High-action items such as sporting events tend to look better in a progressive-scan format, while movies without a lot of change in the background look better in an interlaced format.

The other term that gets thrown around a lot is aspect ratio. This refers to the proportion of screen width to screen height. Televisions come in two aspect ratios. The first is 4:3. This is the screen shape you probably think of when you imagine a TV. The second is 16:9. This is a panoramic view much like that of a movie theater screen. Many 4:3 aspect ratio TVs have a mode that allows them to emulate the appearance of 16:9 TVs by adding a black bar to the top and bottom of the picture. If you've ever watched a letterboxed edition of a VHS or DVD movie, you know what this looks like. Which is better for you? If you're mainly going to watch movies, then the 16:9 aspect ratio sets are definitely worth the additional cost. If your focus is broadcast TV and sports, a 4:3 set will probably be fine. In the future, broadcasters are expected to begin using the 16:9 ratio for TV programming and sports, but currently very few do.