Lux Absio Bervatum

Tuesday, August 8, 2023

Overcoming RF interference with old coaxial cabling

The Wi-Fi at our house has gotten worse over time. Or, more accurately, the RF environment in our neighborhood has gotten noisier. Which is to be expected. Density has been increasing and I imagine the number of RF-emitting devices has increased as all sorts of electronics have become cheaper, smaller, more energy efficient. We went through a few equipment upgrades trying to keep up— new Wi-Fi router, mesh range extender, different adapters. But it's been especially bad in certain areas, like the upstairs room where my main computer lives. Much packet loss. Here is a screencap of pings from before and after I finally got it fixed: 

I have to do a lot of remote desktop work and the packet loss was making that intolerable. I'd be remoting in, typing "8-7-23" and it'd come out "8-------------7-23." Very frustrating.

Of course, hardwired ethernet would solve this. But the layout of our house, with a set of stairs and many walls between my computer and the router, made this challenging. I'm not fussy about appearances, but Cat 5 cabling tacked up against the ceiling in most rooms is not a favorite look. But what other option is there?

I put up with the bad Wi-Fi for months. I figured out that I could disconnect and reconnect to our Wi-Fi and the connection would get a little more stable for a few hours. But it would degrade over time. I imagined there was someone in a nearby house doing the same thing, both of us jockeying for the least-crowded WLAN channel, like a Wi-Fi shoving match. Until one day it occurred to me that the previous owners had nearly every room wired for cable. Cable that we only use for internet through a single coax port in the living room. Was there some way we could use that to set up a hardwired network inside the house? Yep!

This is the product I decided to use. The ScreenBeam MoCA 2.5 Network Adapter. Lets you run ethernet over coax. Apparently, if you have a nice, modern cable provider you can even use these adapters on the very same wires that bring in internet, TV, and so on. But our cable provider is not nice or modern, so I had to figure out something else.

Since we only use the incoming cable signal in one place (the modem), I just had to wire that port to the provider's line directly (isolating that run from everything else) and connect the coax ports needed for networking. This got me very close to the router, but not the same room. I still had to run a single Cat 5 cable through a wall but at least it was a straight shot. Only had to get the RJ45 crimper out for one connector.

And now it's all done! Rock-solid hardwired connection, zero packet loss.