Yes, you can do that. I have 5 modulators tied to a combiner. It is the same sort of thing that was commonly used in motel systems. My setup feeds each of 4 modulators with a digital converter box each tuned to a different local digital channel and a 5th modulator is fed by a dvd player. All 5 modulators feed the combiner, and the combiner output feeds a single coax to the tv sets. The combiner can accept input from 24 modulators and output the signal on a single coax. This is just like the combiner I use.
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