Question: Can I record TV (digital cable) without a DVR monthly subscription or HTPC?

I have my Sony HDTV connected directly to Comcast basic cable. I've been using a DVD recorder to record shows manually. Now that Comcast has switched to digital, my channels have become decimals like 7.1, 7.2, etc so my DVD recorder can't select the right channel anymore (it only does whole numbers).

I hooked up the free Comcast provided digital adapter to the DVD recorder only and now it can see all the channels controlled by the Comcast remote as channel 3. This means I can record channel 3 and whatever the real channel it happens to be set to, but if I want to record multiple channels, I can't do it without manually changing the channel since all the recorder knows is channel 3.

Is there a way I can record shows without paying a monthly subscription for a DVR? I know I can build an HTPC with a TV tuner and run media center software but if there's a box or something easier I could do that would be preferred. I would just get a cable box, but the limited basic cable plan I have has all the channels I need in HD for $14.50/month while the cheapest plan with a cable box is $68.49/month.

Would this work with my DVD recorder?

Or this to record directly? - One-Stop place for Full HD 1080p HDMI A/V Switcher Digital HDTV Tuner Receiver Media Box, HD Media Player, HDTV Tuner Set top Box, HDTV PVR Box and more...