Sitting in my closet, were a couple OTA Digital tuners which were being handed out by the FCC, before the Digital conversion. I obtained them in the event my neighbors, or family, did not get them before the coupon expiration deadline. I never used them, because OTA around here was terrible, unless you had an outdoor antenna. Of course, as I noted in the first post, OTA around here has improved greatly.
The deviecs are called "PalPlus" and were made by Echostar. Very simple. Antenna In; Antenaa Out or RCA Audio/Video out. The best these can do is 480i. Howver, out of things I tried, this did the best job picking up signals; some very fringe signals. THe digital signal is about 10% better than the Homeworx, which is suppose to be more recent technology. They also come with a very nice Grid EPG (very similar to Dish's older receivers) and a nice remote (Hoemworx coudl learn what a decent remote can do). Considering almost all the subchannels, in Denver, run at 480i anyway, this is a reasonable solution. That is, I can look at a grid and see what is on. Again, this is not perfect, no HiDef, No Composite, not DVR, but does a better job than the AM21 and the Homeworx solution (a remote that semi worked and a unstable box). My bedroom TV only has one HDMI anyway, was a monitor, and never had a tuner. I ended up gettimg 60 channels on my bedroom TV, and 40 channels on my living room set. Pretty good with an AmzaonBasics Amplied Flat Antenna.
Finally, I know there are merits to the AM21, but it is most effective if one lives in the middle of an DMA, and have to rely on a database being miantained. It is ironic that I cam across an article that DirecTV may drop local channels to free of space (the article is from last year). If that is the case, they need a more robust solution than what they are offering now.