never messed with dtv, but i do know that if you use one of their switches it has a place for antenna/cable and can be used as a splitter even if there is no sat connected, i've seen this work on many former illegals, i'm not sure if you could use the switch if there is only one receiver or not, but if there are at least three(sounds as though there are) then there ought to be a switch installed and i haven't ever seen one that didn't have an input for ota/catv..........now whether or not you have to use a diplexor at the end of the run to plug into the receiver like a dish receiver, or if the switch will do the work through the sat in port i can't say, but i'd try it all the same. maybe i'm missing something in the configuration, but this seems to be an easy fix.
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