Those are very misinformed rants in those links. HD radio won't harm AM stations. It may cause a problem from low power FM's though they only have a broadcast radius of a few hundred feet. LPFM is what is used for the "talking houses" you see on the for sale sign. I recently purchased a HD radio and I will say it's nothing really special. I also collect vintage radios and they work fine pulling in the few AM stations left. The big problem is when the mandatory switch to HDTV happens. That will render a lot of portable TV's and receivers obsolete. Unfortunately, AM radio is dying and there isn't much we can do about it. I spent 20 years in radio and sometimes miss it.

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