Introduction

It has been an uphill journey, a long battle, and a slow process. But, HDTV is becoming a reality in the U.S. The switch from analog NTSC to digital ATSC (DTV) is quite similar to the change from black and white to color broadcasts which were first witnessed back in 1953. In 1996 the Federal Communications Commission "loaned" an additional 6 MHz of spectrum frequency to every commercial television broadcaster in America. It was hoped and planned that by 2002 every commercial over-air station would have a DTV signal being broadcast. Well, 2002 is upon us and that is clearly not the case. While behind schedule, there are DTV stations available in most major cities. By 2006, the FCC has ruled that every broadcaster must choose NTSC or ATSC and the extra 6 MHz will be taken away. Clearly most, if not all, stations will choose DTV. So, what are we looking at here? Will we all be watching DTV by 2006? Well...Kind of. As most of you know, the new broadcasts will require a Digital Television Set. Old sets will work but will need a digital converter in order to view the program. This is speaking specifically of "Over the air" broadcasts. It is still unclear how cable and satellite providers will adopt the new system.

DTV and HDTV

Well, that's great! But what the hell is it? DTV refers to digital television as a whole. It is the way the broadcast is sent out. What a broadcaster chooses to do with this digital broadcast is up to them. They can break the 6 MHz down into sub-channels, giving them multiple content with one broadcast. Or, they can use the whole stream to deliver a true HDTV quality picture. High Definition Television gives 1080 lines of resolution. It is also broadcast in 16x9 format, closer to the aspect ratio of most widescreen movies. NTSC broadcast are currently in 4x3 format with 480 lines of resolution. Compare that to playing Quake at 640x480 and 1280x1024, only add a couple of inches to the width.

So, where does this leave television sets and the card we are reviewing today? The HDTV sets that are available in stores today are VERY much like a computer monitor. In fact, most of them will handle 800x600 or 1024x768 computer resolution along with 480i, 480p, and 1080i broadcasts. Let's delve a bit into what the "i" and the "p" indicate. High-Def broadcasts are usually either 720p or 1080i. The "p" indicates Progressive Scan and the "i" represents Interlaced. A computer monitor, for instance, uses Progressive Scan and a standard television is Interlaced. The interlaced picture displays half of the scanlines on one cycle and the other half on the next. When a computer monitor is running at 60Hz, it is refreshing the entire picture 60 times in one second. Sometimes we can see this refreshing as a slight flicker. While some broadcasters send out a 720p broadcast, it is normally unconverted to 1080i by the tuner. This brings us to another point. Most high-definition television sets that are sold today are "HDTV ready" and do not include a tuner for DTV. A DTV set-top tuner must be purchased in order to receive the DTV signals.

The AccessDTV Card

Remember how we said that an HD television is very similar to a computer monitor? Well the same goes for the reverse. You computer monitor will actually handle higher resolutions than an HDTV. What AccessDTV have done is create a DTV tuner in the form of a PCI card. This way, you get the benefit of watching DTV channels without having to buy a $1500-$6000 digital television. Here are some of the features of the card.