Comcast DTA and Computer Question?

So i have a computer, i got a Pinnacle 800i, the nicest PCI one with og, digital, and QAM capability. In my old apartment last year i could watch my comcast cable just fine without a DTA. Now it is not working, so i went and picked up a DTA. Now windows media center is saying that i need some sort of IR blaster or something like that. Do i really need the DTA? Is there Any way i can get it working without the DTA? Is there a way i can get it working without the IR blaster? Thanks.