-- You may need to use a 4-way splitter with the "extra"...

[mdk]

@Nighthawk6 -- You may need to use a 4-way splitter with the "extra" leg going to your DCX3510.

My "organization chart" diagram, above, requires a 4-way splitter, but only if the Portal is in the same location as the other devices. The coaxial-cable from the Portal's wall-port probably leads back to a splitter inside the "demarcation box" on the wall of your house, and so a 3-way splitter (phone, modem, Gateway) is needed.

 For best "signal-strength" to all 4 devices (modem, phone, portal, gateway), it is best to use a 4-way splitter, rather than a 3-way splitter (portal, gateway, and one more cable) and then a 2-way splitter from "one more cable" feeding modem & phone. It's difficult to decide which device(s) require the "better" signal-strength, and which devices are OK at the end of the second splitter.

@WinnipegMike -- with the 4-way splitter, try wiring as per my chart, but start with only one device physically connected, say the cable-modem. If OK, then connect the Gateway, and test both devices. If OK, then connect the Shaw Phone, and test all three devices. If OK, connect the Portal, and test all four devices. If OK, disconnect the Portal, and connect the DCX3510, and test all four devices.  Tell us the result.

Another chart:

Of course, you can eliminate the 2-way splitter if you eliminate the Portal.

[WinnipegMike]

Wow, MDK. Great replies. I would love to see this to completion and it was my house, I would! But since it is a friend’s house, I am not going to mess with their system anymore! I already “broke” it once by putting the DCX on the “portal lan”. My friend agreed that just getting a portal from Shaw to go with their current configuration was a better idea than messing with the DCX, which will be returned to Shaw.

From what I could tell, it appears that their Gateway/Portal is a created by the Gateway (coax in) and the portals all run off the same coax out from the Gateway (with splitters) to the three existing portals. So the portals are not configured like your diagram.

I will see what I can do when installing the new (fourth) portal when it arrives. Can it go on a splitter before the Gateway?

I did not see a demarcation box in the electrical panel anywhere.

[mdk]

@WinnipegMike -- the portals are not configured like your diagram.

Hmm. The Gateway uses MoCA.

MoCA (Multimedia over Coax Alliance) is a technology that uses the existing coaxial cables already in most people’s homes. In essence, MoCA creates a wired Internet home network, but without the headache of drilling holes or running wires.

So, if you trace the "inside-the-walls" existing coaxial cables back to where the single coaxial-cable feeds in from the telephone-pole, you should find the Shaw demarcation box, and a coaxial-splitter inside that box. So, the MoCA signal goes from the Gateway, back to the demarc box, and then down to the Portal. You don't need to have a "direct" connection from the Gateway to a remote Portal. (The first version of the Gateway did not have HDMI output - you needed to put a Portal adjacent to the Gateway, and connect the HDMI cable to the Portal and the TV.)

> I did not see a demarcation box in the electrical panel anywhere.

It should be obvious, with multiple coaxial-cables going inside a "locked" box -- only the Shaw technicians have the special key to open it. It does not need electrical power.