Ok here is something strange that I don't know quite how to explain why it works.
I own the Artec which is of course only ATSC, no analog. I don't own any other USB based tuner, and I am using a laptop thus I can't use PCI based cards. I have MCE on my laptop, but wasn't using it for TV since I had no tuner prior to buying the Artec. I heard all the reports that it would not work without an analog tuner, so at first I didn't bother trying it. But then I decided what the heck.
When I went into setup in MCE I tried the automatic setup. It failed because it could not find a tuner. But then I tried the manual setup. I chose the antenna connection option and then setup my zip code etc. To my amazement it showed guide listings for both ATSC and NTSC. Of course it could not tune to any NTSC channels, but would tune in ATSC.
So this is somewhat contradictory of what I have been reading. One article I read was that the requirement for NTSC tuner was something to do with getting the guide listings correct. My setup now shows NTSC and ATSC listings, but I just can't tune the NTSC.
Maybe this behavior is specific to just the Artec. I have never connected any other tuner to this machine previously, since I have not had access to a USB based NTSC tuner. But it is definately working. My laptop has some cpu utilization issues with some HD channels, but it still works.