Network Diagram

DirecTV and Xfinity Share Cable?

You Will Need A Separate Line
Don’t waste your time trying to mix DirecTV and Comcast Xfinity on the same line. It just won’t work! I spent a lot of time and money trying unsuccessfully to share the cables. Here is the story:

I had been using Clear Wireless Internet (6 Mbps and unlimited use for $49.99 per month)  for over a year, when it was bought by Sprint in October/November of 2014.  Sprint immediately raised the rate 10%, and promptly announced the End-Of-Life for the service.   They shut it down the first week of November, 2015.  (Maybe I can hack my clear wireless box for parts.)

I began shopping for a new ISP in September of 2015, and found an offer from Comcast for an Xfinity package that includes High-Speed Internet at 25 Mbps Download speed, 5 MBps Upload speed, and (as of June 1, 2016) a whopping Terabyte – (yes, 1,000 Gigabytes!) – of data per month, along with Basic Cable Television, plus a free HBO bonus for only $39.99 per month for the first year.  This is a superb deal, even when the rate doubles after the first year.

Lovely! My Internet is running great and I’m very happy with it.

The only problem is that I’ve already got DirecTV and — even with every permutation of Power-Passing Mixers, Power Isolators, Multiplexers, de-Multiplexers, and Duplexers, — there is always interference between the two services because they share a large band of their frequency spectrum.

My home is wired with two DirecTV cables: One is non-powered and distributes the DirecTV channels from the SWM16 to a splitter, which distributes the signal throughout my home.  The other cable runs from the SWM16 directly to my SWM (Single Wire Multiplexer) Power Inserter and my main DVR/Receiver.  The SWM power has to remain on the SWM16 port to power the satellite dish LNBs.  With that one constant, I’ve tried every imaginable configuration on both the non-powered as well as the SWM cable, but I did not find any acceptable configuration that will successfully share Xfinity with DirecTV cable signals.

On some configurations I did get some signal; just not all channels on either service when I try to share a cable segment.  I could almost live with that, except that some segments, after the first mixer/duplexer, go completely silent as soon as I add Xfinity to the cable.   (I suspect that the mixers/duplexers — and I’ve tried several different brands and types  —  introduce a phase shift between the signals at those channel’s specific frequencies, which effectively cancels those channel bands.  That, or maybe the interference between the signals is so great as to render them incoherent to the receivers. )

I had searched the Internet extensively for a solution to this dilemma long before I even got Xfinity because — being the genius that I am — thought ‘Surely, I can get this to work‘.

Sadly, I cannot and I finally resigned myself to run a separate dedicated Xfinity cable.

The Only Working Solution
So save your time, sanity, and the hundreds of dollars I spent on all those Muxes, DeMuxes, Power Isolators, Power-Passing Splitters, Combiners, and other parts (that did not solve the issue) and just run the new cable.


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