Originally Posted by DaylightDan
I have a Tivo HD DVR without cable cards and am wondering if I still need the Comcast cable box to view channels 21-77 which were analog but will be converted to digital next month. The key here is I do not have cable cards installed and just use this DVR for channels 2-77. Will the HD DVR convert the digital channels (22-77) or do I need the additional cable box from Comcast?
You and the guy who posted before you are really in the wrong forum. This forum is for people who have Comcast cable boxes that run TiVo software.
As for your situation, TiVo HDs weren't made to work with cable boxes. They were made to work with cable cards, which allow the TiVo to become its own cable box.
As for the TiVo being able to tune digital channels on its own, that depends on whether your area has its basic channels (digital versions) scrambled or not. In some places, you can tune all the expanded basic channels, unscrambled, using just a QAM tuner, which your TiVo has.
In some areas, Comcast scrambles all channels, except for the ones they legally can't. (Namely, the local channels which you can also get OTA. They're required to carry OTAs unscrambled.) If you live in one of those areas, you'll need cable cards from now on.