pna

It was very helpful to learn that the coupon-qualifying tuners are essentially worthless for my purpose. I had given up on finding any kind of set-top box for channeling digital broadcasts to my front projector. Most of them - including the Coby DTV-140 and the Samsung DTBH260F - are "currently unavailable," suggesting they are either obsolete or unreliable. The DTVPal DVR is basically a converter box, and the Dish Network DTVPal DVR is for satellite, which defeats the purpose of getting free TV.
Therefore, I have turned my attention to the newer DVD recorder/VCR Combos, averaging about $230, that have both a Built-in Digital Tuner and HDMI. The ones currently available include the Panasonic DMR-EZ48VK, the Toshiba DVR660 and the DVR670, the Magnavox ZV457MG9, the Sylvania ZV450SL8, the LG RC897T, and the JVC DR-MV150B. Of these, the Panasonic seems to have the best tuner - my main criterion - while others may have a better remote or superior recording features (timer/ability to record digital programs on tape). I'm not sure what the advantages and disadvantages are to these machines, but it seems to me that the extra $100 gets you more recent technology and greater versatility. I have always shied away from multi-purpose machines, due to break-down issues, but in this case they seem to reflect the most recent technology, and none of the set-top boxes seems to be so simple and dependable as one would hope.