KDKA is doable if you want it badly enough. You're going to need an UHF antenna with about 13db of gain, though. If you want 11 and 9 as well, you'll need a VHF combo. You'll want to point the antenna directly at KDKA and rely on the stronger signals to get picked up by the back of the antenna, so no reflector either.
Something like a Winegard 7084P
http://www.solidsignal.com/pview.asp...enna-(HD7084P)
Depending on how long your cable run and what your splitter setup is, you may need a preamp as well. The CPA-19 is a good choice
http://www.solidsignal.com/pview.asp...lifier-(CPA19)
To do it right, you're going to want it mounted outside on the roof, too. It's big, so you're going to want help.