I'm still not sure if my last diagram will work... when I put the MoCA signal on the coax before it gets to the modem doesn't that put MoCA all the way back up to the telephone pole running behind my house? My modem (Comcast) doesn't have two coax connections.

sure but it'll also send it to the cable box area. The splitter isn't a one-way thing.

errrr. (car forum) there's no check valve on the splitter.

Could be a check valve on the splitter that the Comcast guy put in on the side of the house where the coax comes in.

Yes

Where the Spectrum enters your house what does the split look like?

I'm assuming coax comes into home, there is a splitter, one leg goes to the router and one leg goes to the cable box / boxes?

Yes, things are just like my last diagram. I'll post a picture of the splitter. Hopefully that splitter is special if it needs to be. I think the potential problem is I don't have any coax "behind" a router.

Here is the splitter just after the coax comes to the house from the telephone pole.http://forums.pelicanparts.com/uploa...1640190120.jpg

To help clarify - here is the current solution under consideration.http://forums.pelicanparts.com/uploa...1640192029.jpg

Interesting.

So your DVR authenticates back to the provider on it's own and not through the router which is more standard.

And the router authenticates on it's own as well.

I'm hoping on a plane in a bit so if I'm not active I'm not ignoring this, just travelling.

There is some internet discussion on keeping your MoCA from getting over to your neighbors.

This is recommended.
https://www.amazon.com/HOLLAND-ELECTRONICS-3-WAY-BALANCED-SPLITTER-MOCA-COMPLIANT-5-1675MHz/dp/B01552LYL6/ref=cm_cr_dp_d_rvw_txt?ie=UTF8

There is also this "filter".
https://www.amazon.com/Filter-MoCA-Cable-Coaxial-Networking/dp/B00DC8IEE6/ref=cm_cr_srp_d_product_top?ie=UTF8

New info. The coax coming to the house before the splitter has what I thought was just a connector but it is a MoCA filter. Model GLP-1G70CW MoCA® Filter. I'm guessing this is to keep stray MoCA signals out of my house and keep my MoCA signals from getting on the Comcast network. So Comcast knows about MoCA and I suppose they want to keep their network clean.
I also went to the Comcast/Xfinity store in person and asked. One guy I talked to said almost for sure my modem/router (gateway) from Xfinity is putting MoCA on the line (coax).
@stomachmonkey - you may be exactly right I might need only one MoCA adapter.
I was also reading about the two MoCA objects or adapters need to pair with each other but this should be automatic.
We'll see - stay tuned to the continuation of this exciting story.

Ms Gogars xfinity is the same and plugs into the coax and does its business however it does.

I don't have cable, just Xfinity internet and an Arris something or other. I passed on the Xfinity router.

Pictures of the filter I found already installed by Comcast.

Filter and Splitter
http://forums.pelicanparts.com/uploa...1640230863.jpg

Close up of Filter to see part number
http://forums.pelicanparts.com/uploa...1640230863.jpg

Some progress. As mentioned, the guy at the Xfinity store said my modem has MoCA. This morning I went into the modem using 10.0.0.1 and low and behold the option to enable MoCA on was there. I enabled it and saved the settings. So I probably only need to insert one MoCA module at the TV location to get an internet connection. Stomachmonkey was correct. Stay tuned.

Here is a good intro. to MoCA.
https://www.youtube.com/watch?v=I9Vro0d38pA

MoCA signals are passed over the coax at a much higher frequency than the TV cable signals so it doesn't interfere with the TV cable signal and can be running at the same time. The MoCA signal degrades fairly quickly so it doesn't go very far maybe to your neighbors house but not more. I suppose the recommended MoCA filter stops even that from happening. This is all very interesting, especially since I'm trying it myself. :-)

I feel good. The MoCA adapters came today. I plugged one in at the TV DVR and supplied power and it worked. This is after I enabled MoCA on the Xfinity modem. It picked up the MoCA coming out of the modem about 120 feet away over coax. I'm getting about 120 mbps download over the ethernet patch cable coming out of the first MoCA adapter. That's enough I think for watching Netflix/etc. This is probably the end of the story unless people want more detail. Many thanks to gogar and stomachmonkey.

This just in:

Check out the "xfinity stream" beta app on your roku and it will do everything your cable box does inside the roku, if you want! Eliminate the cable box.

I don't think it will do the record function ?
I'm getting close to being able to cut the cable.

Looks like it has cloud DVR just like my Xfinity DVR... very cool.