Series 2 is not new tech and you need to connect the cable box to the composite (yellow) and audio (white/red) inputs. You would not get good video quality on a HDTV, but under best recording quality it may not be as bad.
Series 2 (PLS, sold)
TiVo HD 1TB (157 HD Hrs, PLS, "652")
Roamio! Oh, wait, Its Juliet!
OTA! OTA! OTA!
The TiVo Apocalypse begins on Sat 2013 Feb 16 00:00 GMT!