If there is only one receiver and you aren't trying to use DECA for connecting to the router, diplexing should work. The DECA signal out of the receiver may interfere with some OTA channels but you could install a bandstop filter at the input to the receiver to block this. Of course it is unsupported and future expansion is limited but it will work for feeding OTA to a AM21. It might also be better to not use green-label splitters.Davenlr said:Jodean, the receiver he said he has, contains built in DECA. Deca uses the same frequency. He would not be able to do what you say he can do, with that box.
Those of us who already have dual coax installations (from the pre-SWM days) have an available cable to use, which is preferable, but not everyone can do this.