[mythtv-users] Revisions of Air2PC

[Mario L]

Are there several revisions of the Air2PC ATSC card floating around? 
Are they all compatible?  I have seen several different pictures of
cards that are called Air2PC ATSC, but some say that they will
"receive an internet signal if you have a provider in the area" and
some that say they recieve a digital television signal but have no
mentions of HD.  I don't want to make the mistake of spending cash on
a card that won't do HD for me, so could someone enlighten me?