Outdoor Coax Cable and Splitters?

June 23, 2021 3:28 PM

I need to make a small change to the coax wiring situation for/outside my house so I can use a MoCA (Multimedia over Coax) adapter in one room, which has a wall coax thing that’s currently not connected to the live coax line. This will require a short (1 foot?) coax cable that is suitable for use outside, and potentially also a 1 input, 2 output splitter that is suitable for use outside and is compatible with MoCA use. I’m confused about options, can someone point me to appropriately weatherproof choices either at Lowes/Home Depot or on Amazon?

(Basically, whoever installed the Comcast internet bypassed the 4-way splitter outside that feeds into coax different rooms in the house, and just connected the live coax to one line that goes directly into our living room. I need to either connect that back to the 4-way splitter or to a new 2-way splitter so it’s connected to the one line going into my room. Other rooms aren’t important since wifi reaches them fine.)

posted by needs more cowbell to Technology (10 answers total)

You can get rubber boots to go over the F-connector on coax cables and splitters. With that, it should be fine. Yes, you can get outdoor-rated, UV proof coax, and it will last longer in the elements. But unless it's hard to access and replace if it has a problem, I personally probably wouldn't bother. The best solution is to get an outdoor enclosure and do the connections inside of there, but I have had splitters in the elements with a boot, and they survived for years. Sort of a "what's ideal" vs. a "what will actually work" situation. Since the failure mode here isn't very severe (it's not like electrical, which can burn your house down or kill someone if you cut corners), I tend to just do it the simple way unless and until I have a problem.
posted by primethyme at 3:34 PM on June 23, 2021

Sorry, I meant to add some links and got distracted. Here are some examples of the kinds of things I would buy.

Rubber boots.

Splitter.

Cable.

If you really want to, you can buy outdoor cables, but they probably don't come in short lengths.
posted by primethyme at 3:40 PM on June 23, 2021

Response by poster: I guess the boots are the big thing I needed to know about. My aim is basically to match the level of weatherproof-ness that the current setup has, because my housemates/the people I’m renting a room from will probably be here long after me and aren’t up for this sort of fix-it adventure and I don’t want to leave them something likely to fail (for weather-related reasons) sooner than the current setup. (There’s no enclosure currently and there’s a grounding wire thing installed that I think would make it hard for me to put an enclosure around & that I can’t move. But the current live cable connection does seem to be protected with boots or just has ends that have some kind of weatherproofing on them.)
posted by needs more cowbell at 3:59 PM on June 23, 2021

If you're worried about issues after you leave, just remove the splitter and extra wire before you go.

Comcast uses the CommScope SV-2G in my area. It's rated 5-1002MHz. I've got one sitting on the shelf that the installer gave me in case I needed it. If the signal levels on your cable modem are above 2-3dBmV or the 4 port is one of the directional ones that has one "hotter" tap rather than all of them being the same you could try just using that before bothering to spend any money on the project. If it has a grounding lug, you can safely move the ground over and bypass the grounding block entirely. If not, you'll need that short wire to go between the grounding block and the splitter.
posted by wierdo at 7:06 PM on June 23, 2021

Monoprice has 1.5 foot RG6 cables, by the way.
posted by wierdo at 7:10 PM on June 23, 2021

1. It’s a likely situation that a previous person had a low signal problem and bypassed the 4 way splitter. Splitters will reduce overall signal downstream (they split it!) and introduce noise in the entire coax system if there’s an open port that’s not terminated. It is possible splitting the signal could reduce it so much downstream that it doesn’t work for what you need. Just be aware and keep the splits to a minimum. The cable company can crank the signal up, to a point, if this is a problem.

2. Use “coax-seal” on connections outside. It’s a gummy plasticy tape that comes on a roll. It’s used a little like you might imagine electrical tape to be used. It is weatherproof almost immediately. A close second is silicone cable wrap tape, which is less tacky but more difficult to apply well. Some times I use both. No other preparation for coax is required if the connections are water tight.

Don’t forget a drip loop!
posted by Geckwoistmeinauto at 7:18 PM on June 23, 2021 [3 favorites]

I use this Coax Seal putty if I absolutely have to, like in a weird corner or something. But I much prefer this self fusing tape, which is a silicon tape that wraps like electrical tape, but then becomes a single unbroken piece of silicon, it's weather resistant and good up to 260°C.

ETA: Geckwoistmeinauto, jinx!
posted by Horkus at 7:21 PM on June 23, 2021 [3 favorites]

If it doesn't need to be pretty, depositing a tube of RTV silicone over everything has worked for many cheap ham radio antenna installations with non-weatherproof gear.
posted by eotvos at 7:22 PM on June 23, 2021

If you use an RTV, be sure to use an electrical grade one. Some of the ones used for the usual home sealing tasks contain acids that could corrode metallic parts.

Personally, I would stick with the tapes and putties mentioned above.
posted by ZenMasterThis at 3:41 AM on June 24, 2021 [1 favorite]

Also came in to mention self-fusing tape. At the big-box DIY stores, I've bought Scotch 2228 and use it to weatherproof all the outdoor coaxial connections for my amateur radio antennas. Super easy to use and relatively straightforward to remove down the road. Cut a piece a few inches long and stretch it while wrapping it around the connection. That's pretty much it.
posted by jquinby at 6:05 AM on June 24, 2021