Just gave my media center PC the last device that will physically fit (I'm now out of expansion slots and bays. FVCKING FEAR ME) - a Leadtek TV2000 XP. After a lot of finnagling with my best FM/TV antenna (I don't have cable or satellite TV), I can only get 1 FM station, and 1 TV station in usably. This was achieved by sitting the antenna right in front of a window facing the city. The reception was absolutely horrid when it was by my computer, and it actually got worse when I tried to put a lid on any interference by closing the case 
The two channels that I get in are 13 (CBS) and 97.9FM. The furnace is about half the distance from here to the window - could I possibly use the air vents as a giant antenna?
The two channels that I get in are 13 (CBS) and 97.9FM. The furnace is about half the distance from here to the window - could I possibly use the air vents as a giant antenna?