If I read your question right, you are looking for a diplexer to combine UHF/VHF television signal on to the same cable as the satellite signal. A lot of people use a true diplexer, but it isn't neccesary. A two-way splitter will work just as well, and they're easier to come by. It makes no difference which way you are sending the signal, they are still separated by frequency and won't interfere with each other.
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