Is a Comcast Box Necessary for HD?

In order to use the On Demand service from Comcast, each HDTV television will need to have its own separate converter box. Comcast offers cable card alternatives for some regions, and you will be able to receive some HD content if you choose this option, but On Demand and its on-screen television guide will remain locked out for all televisions lacking an HD box.

CableCARD is an option offered by some cable providers, including Comcast in some regions, for televisions containing built-in HD tuners. A CableCARD is credit card sized, that you slide into the side of your HDTV in a specific port. It contains all of your subscriber information, and relays to the television what channels you have and have not subscribed for.

Over-the-air HD refers to HD channels broadcast over the wireless spectrum in much the same way analog television channels are. An HD antenna can range from a flat, envelope-sized piece of plastic mounted on top of your television, to a large roof-mounted antenna. Comcast is not the provider of over-the-air channels.

In most regions there is at least one alternative to the main cable provider. For example, satellite television providers provide HD channels, and so do the fiber optic providers typically owned and operated by telephone service providers. You can also investigate the various providers of HD video content on the Internet.