I have a Series 2 DT in center city Philly where, since about 6 months ago, the majority of my basic Comcast channels no longer work without a cable box

I have continued with the no cable box setup and have lived with a severely reduced channel lineup as I didn’t want to possibly/probably lose the DT ability while my wife’s shows were on and all happened to be on local stations and a few cable stations we still had.

I am now finally about to do the setup with the cable box. When I set up Tivo with the cable box… one tuner will get the feed via the cable box while the other tuner gets the feed from the cable line directly. This raises some questions:

1. The channel line up is different when I use a cable box as opposed to when I do not. For example CNBC might be channel 2 with no cable box but is channel 20 with the cable box. Will Tivo be able to recognize this and function properly?

2. Even if it does recognize that each tuner has a different channel line up, will it realize that the tuner with no box connected only gets about 20 channels? I’m guessing no since the Tivo currently tries to record programs on scrambled channels.

I think I’m basically screwed here and will be reduced to a single tuner. If this is the case I suppose I should just leave the "no cable box" line unplugged?