High-definition television has been growing in popularity since its inception in 1996, and today, it?s starting to really take off among consumers. By the year 2008, it?s projected that 45 million households will have an HDTV set in their home entertainment room. Once you?ve seen a digital HDTV broadcast, it?s not hard to understand why.

Compared to standard analog TV, the improvement in picture quality is truly remarkable. The resolution and clarity are dramatically superior, and the HDTV format?s widescreen (also known as 16:9) aspect ratio offers a thrilling ?you are there? perspective for watching sporting events, movies and favorite shows. In addition, HDTV?s Dolby Digital 5.1-channel surround sound adds to the astonishing realism.

However, there?s a catch. Sometimes what the program providers call ?HDTV? isn?t really true HDTV.

Yes, you read that right. In fact, the number one question consumers ask a leading HDTV accessory manufacturer?s customer service department is, ?How do I know if I?m really getting HDTV from my new high-definition set??

The short answer is that it?s guaranteed ? if you use an off-air antenna to receive HDTV broadcasts.

On the other hand, sometimes the quality or resolution of HDTV broadcasts can be compromised by a cable or satellite provider, because of economic or technical considerations. Also, they might not offer all the local HDTV programming choices available in your area.

True HDTV is usually broadcast in two different formats: 1080i, which is 1920 x 1080 pixels (the tiny picture elements used to create an image) interlaced, and 720p, comprised of 1280 x 720 pixels progressive. (A third HDTV standard, 1920 x 1080 progressive, exists, but broadcasters aren?t using it yet and only a few sets can display it.)

Interlaced images are displayed by splitting a frame of video into two halves every 1/60th of a second, with each odd and even row of pixels displayed alternately to create a complete image. Progressive scan images are continuously drawn on the screen every 1/60th of a second. All HDTV formats offer vastly greater resolution than standard analog TV, which uses a 480i interlaced signal.

However, the increased resolution of HDTV requires much more bandwidth for transmission than analog TV ? and there?s only so much bandwidth available on a cable feed or satellite transponder. As a result, although some cable and satellite providers do offer true 1080i and 720p programming, many don?t, and use data compression or other techniques to reduce the bandwidth or the resolution of the HDTV signal, to conserve precious data ?real estate.?

The result is compromised image quality. For example, some cable companies use forms of data compression called ?bit-grooming,? ?downconverting,? or ?downresolution,? which automatically removes half the horizontal and half the vertical pixels from an HDTV image, resulting in a less-detailed picture with only one-quarter the pixels originally intended for viewing.

These same bandwidth restrictions also limit the amount of HDTV channels a cable or satellite provider can carry. In many cases, local HDTV channels are simply not available in your area via cable or satellite. As of April 1, 2004, only 382 out of 1175 HDTV stations are being carried on cable HD.

So, how do you know if what you?re getting from your cable or satellite provider is true HDTV? Good question ? and if you call to find out, you might not always get a clear answer from the customer service representative on the line.

An off-air antenna, on the other hand, is the only guaranteed way of receiving true HDTV, exactly the way the network intended it to be broadcast. That?s because it receives the digital HDTV signal directly from the broadcast tower, with no data compression or downconversion. By using an off-air antenna optimized for HDTV reception, you?ll be assured of receiving HDTV programming in full resolution and Dolby Digital 5.1-channel surround sound.

The proper HDTV antenna also provides access to all the local HDTV broadcasts in your area, enabling you to enjoy the full selection of available, no-cost local HDTV programming available from the stations in your area. In addition, an off-air antenna offers access to multicasting, or the simultaneous broadcast of television programming on four or more standard-definition digital channels from a single station. Multicasting allows networks to target such audiences as children, foreign language-speaking viewers and special-interest audiences with additional programming choices.

In fact, some satellite providers recommend augmenting their satellite feeds using an off-air antenna to get your local HDTV channels. DIRECTV, for example, even enables customers to seamlessly integrate their off-air HD channels into their on-screen programming guide and view programming schedules in advance. Another satellite service, VOOM, offers an off-air antenna for local HDTV broadcast reception as part of its equipment package since it does not broadcast any local channels.

To help choose the best HDTV antenna for your location and installation requirements, your retailer or installer can offer invaluable assistance. Manufacturers and their websites are also an excellent information resource. Be sure to check out the CEA (Consumer Electronics Association) antenna-mapping program, www.AntennaWeb.org, which can help you determine the proper antenna to use in order to receive your local television broadcast channels, and in which direction to aim it. A variety of rooftop, attic-mount and compact indoor HDTV antenna designs are available, all optimized for best HDTV reception.

In order to maximize your HDTV viewing experience, an off-air antenna is an essential component, whether you choose to receive all of your HDTV signals exclusively via antenna, or use one to enhance your existing cable or satellite installation.

TERK Technologies manufactures outdoor and indoor HDTV antennas that offer ideal reception solutions for every installation requirement. For more information, call TERK at 631-543-1900, and you can view their full line at www.terk.com.