Digital Television (DTV) signals are broadcast in a variety of ways by different providers. For example, an HDTV signal and a digital satellite broadcast are very different, and must be received and decoded differently. That �s where a set-top box (STB) comes in. Each STB is designed to receive and decode a different type of broadcast. Most DTVs require the addition of an STB because it would be too costly to equip them with tuners and decoders for every type of broadcast. It wouldn�t make sense to pay for a TV with a satellite receiver if you�re only planning on getting over-the-air HDTV. That �s why you�ll see terms like HDTV monitor or HDTV upgradable. This means that the TV is capable of displaying true HDTV, but it does not have a built-in HDTV tuner.

HDTV Decoders and Set-Top-Boxes

Do I need an additional box for HDTV?

Do you really have HDTV?

You've purchased a new Digital HD-Ready TV, and now you're wondering if what you're seeing is high-definition.  Are you getting HDTV?  The answer could be no, because some of the digital TVs sold do not include the HDTV tuner/decoder which must be purchased separately. Does the image get better with the purchase of a decoder?  If you are able to get HDTV broadcasts, the answer is absolutely, yes!  

The Set-top-box dilemma

With the exception of the few sets that offer integrated HDTV tuner/decoder, the purchase of a separate set-top-box is a necessity.  Many manufacturers do not offer decoders simply because it keeps the cost of the new sets down, and some cities in the country simply do not have high-definition broadcasts. (check your city at http://www.titantv.com/) For those without local HDTV broadcasts, many of today's set-top-boxes will offer DirecTV satellite decoder to ensure HDTV virtually anywhere in the country with use of a small dish. DishNetwork also offers HD capable boxes with purchase of a service package. If your service is provided by cable, you may not have any HDTV programming available.  Some cable companies have started HDTV, but the service still requires that you lease a decoder box before you can receive HDTV.

Most HDTV decoder boxes will offer Component input (Y-Pb-Pr), however some will offer both Component and RGB. RCA's DTC-100 is one of the rare units that only output RGB via VGA 15-pin connector commonly found on a PC monitor, which makes this box ideal for use with a front projector or Plasma TV.

Future Development of Set-Top-Boxes

What consumers need is a unified standard between the various providers such as public (Over-The-Air) TV, cable, and satellite.

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