How to setup one aerial cable feeding into 2 set top boxes....

[Mehta23]

We recently bought a Vu+ Linux (yay) PVR, and are using the standard aerial that comes from the wall and a Y splitter to feed in two aerial connections into the box.
I'd like to know the best way for getting a third aerial connection into a Sky box.... I'm thinking another Y splitter would do, but then I don't know how many times you can split the same connection....

Help?

(Sorry for not being technical enough )

 

[general eclect]

I imagine a signal boosting amplifier may be necessary, but that's only a guess as I know diddly squat about antennas and their signals...