You have to have a multiplexer. I first used the TriplePlay one (I forget the maker), but I replaced it with a ChannelPlus one I got on Ebay when it died several years later. You can use the output of the 522, but I found a dedicated multiplexer with their component signal works better. I use a combinations of splitters and joiners (splitters hooked "backward") to accomplish this.
Antenna in attic is mixed in with output of the multiplexer. This is then split to go throughout the house. I have a signal booster hooked in for the runs that go farther from the unit.
I may run everything to a common point in the future, but for now this mass of wires is all in the "entertainment center" area of my living room.