Ed. . you are aware that the whole "HD antenna" thing is a fraud, right?
HD runs on the same frequency as the non HD channel, it's the exact same transmitter and receiver. they just transmit digital (data) instead of analog (noise)
I think it's a sub carrier, but I'm no FCC tech.
possibly upgrading to a modern antenna (like my fractal antenna) is not a bad idea.
I got a design from instructables.com and built one, the same one RCA charges 40 *ballhares*for.
it works great, btw
*Radioshack, you have questions, we have blank stares. *