DECA is fully supported on both SWM1 and SWM2 ports on a SWM8, and the DECA signal travels through the SWM8 from one port to the other.

Wired ethernet also works.

To get DTV to turn it on, you might need to just let them assume you installed DECA.

So it turns out that they require a SWM system for Whole Home DVR. Back when they first tested the media sharing feature, it only required networking between the receivers. I actually had it enabled when it was in beta test, but I didn't continue when they started to charge for it.

Guess this just accelerates my plans to convert to SWM.

DirecTV support rant to follow...

I ordered an SWM and PI from WK - thanks for the fast shipping guys!

Installed it today, and after one false start I got it working. Turns out there's a minimum cable distance between the PI and the SWM. It worked at first, then it didn't. Read about the issue, switched some cables around, and then it was fine. Both HR-21s show 96-100 on the 9 "transponders" for the SWM "satellite". So then it's time to call DirecTV to get Whole House DVR activated...

What a CF. They insist a need the "Whole House Upgrade" equipment installed. I tell them I already have it, they say they can't enable the WHD option on my account until it's installed. I repeat that it's already installed. CS sends me over to TS. They say the same thing. Want to charge me for the equipment upgrade plus a "professional installer visit". I tell them no way. I don't need the equipment, and I'm not paying for an installer to look at my wires and say it's fine. TS rep insists. I insist on talking to a supervisor.

5 min on hold later....

TS rep comes back and says they'll turn on HWD. Great. Asks which DVR the PI is connected through. Not sure why he cares, but I tell him. Reboot both receivers. Wait forever (these are HR-21s). Finally, one comes up as authorized, the other doesn't. The one that is authorized is the one that has the PI in the cable. TS rep asks about the DECA units. I say I don't have any, but the receivers are both on ethernet and I don't need them. He insists I do and the other one (on port 2) won't authorize until I have them. He offers to send me them for free. OK, fine. He takes shipping info, says they'll be here in three days, and to call back if the second receiver won't authorize.

Off the phone after an hour.

I reboot the second receiver (the not authorized one) again. This time it comes up authorized as expected. Configured Whole House DVR on both units and we're all done.

Anyone want to buy a couple DECA units when they get here?

Another interesting point - DirecTV insists you need a SWM setup (as well as DECA) to enable WHD (ala MRV). Well, that's not true either. I was doing some testing today in preparation for moving the SWM to the basement. I disconnected the SWM, and reconnected everything the way it used to be. Then I rebooted the receivers and set to them to Multi-switch instead of SWM.

Guess what? MRV works just fine. No DECA, no SWM. Just an ethernet connection between the receivers.

Right - all you technically need is ethernet, but what you need to get MRV activated (or at least what they need to hear) is SWM + DECA.

I should add that with an HR34, currently, ethernet causes some real problems. So with an HR34 in the mix, you really do need DECA (and obviously SWM).

Hmm. That's interesting. I'm about to switch the HR21s to an HR34 and either an H25 or C31. Given that everything else in the house is direct wired ethernet, and I was planning on using ethernet for those two devices, what's the best way to hook them up to avoid problems? I have two standard DECA adapters to use.

The best way is a DECA Router Package, see:

www.weaknees.com/deca

Insert the Internet onto the coax line using the DRP, then Internet will be on the coax line sent to all receivers. Any unit other than an H24, H25, HR24, HR34, C31 requires a DECA at the unit.

I am, I'm looking at getting a HR-34/SWM and do not want to run seperate ethernet to it.

You don't need/can't use a DECA with an HR34. The HR34 has DECA built in so it does the split internally, essentially.