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Micky,

If you have an HDTV with an ATSC tuner, (for over a year, all new HDTVs sold in the U.S. should have this digital tuner), then you can capture an over the air HD signal with an antenna and play it back on your HDTV.

You don't need any HDMI or Component cables for this. The antenna connects directly to the TV and feeds the signal to the ATSC tuner in the TV. It's basically the same way an old rabbit ears antenna would capture an analog broadcast signal out of the air and display it on your old-timer TV. In fact, for some people, that old rabbit ears works with their new HDTVs.

Let me know if that answers your question.