My home office has a few cords coming out of the floor. One of them appears to be ethernet*, and the other goes into a small plastic box with two ethernet* ports labelled “Phone Lines 1 & 2” and “VDSL in DT Out”.
I’m pretty sure I know where the other ends of these are, or at least can make some decent guesses. I’d really like to be able to utilize them if they ARE ethernet, because I’m using wifi for my office computer, and being able to be hard-wired into my router would be sooo much better.
Anyway, other than just plugging it into my computer, finding the other end and plugging that into my router, is there any other way to test to see which wire is which? I’d spend a little money if there was a device at the hardware store or Best Buy or something that could do it.
*I know there’s a difference between CAT5 and CAT6, but I’m not sure I’d be able to spot the difference. Is there an easy way to determine that as well?
Wait. You have random cables in your house that you don’t know what they plug in to?
As to Cat 5 v. Cat 6, no meaningful difference. They’re mechanically similar cable, but Cat 6 is shielded and insulated a bit better to reduce crosstalk and allow higher guaranteed signaling rate. Original Cat 5 permits Fast Ethernet (100 mbps) to its maximum length, but it’s kind of outdated now and not found in decent installations. Enhanced Cat 5 (Cat 5e) goes up to Gigabit Ethernet. Cat 6 is up to 10 Gigabit Ethernet. And the cabling itself is almost visually indistinguishable (Cat 6 is apparently slightly larger diameter than Cat 5 variants, but try to figure that out with out comparison to a known example of one of those.)
Depending on testing tools, you can learn whether the connector is plugged into anything that generates an IEEE 802.3x link signal (i.e., some kind of Ethernet). Sophisticated testing stuff can tell you it’s not plugged into anything at all.
You may be better off trying to figure out where the other end of those cables go and see what (or if) they connect to anything. But if you installed your router, and you don’t remember plugging in some LAN cables, what would those connectors be connected to?
Too late to edit, but a good literal answer to your question is a cable tracer like this (random Google return) to send a pulsed signal down the wire from the end you know so you can find the signal coming out of the cable at the other end. That way you know you’re not plugging the computer into a cable that’s already plugged at the other end into an Etherkiller or something evil like that.
I don’t own that particular one, but one damn similar, and it’s been very useful tracing phone, LAN, and coaxial all through my (large and eccentrically wired) house.
The mystery line may very well not be Ethernet “RJ45” type connections. There’s a ton of different RJ connectors. Look for the number of contacts, etc. to get an idea. Some two-phone/DSL systems have 6 contacts (6P*) or maybe even 8 like Ethernet.
Anything phone-related might connect to the POTS at the junction box.
My house was built in 1972, and I purchased it in 2014. There have been a few additions made along the way, I’m sure.
It won’t be connected to anything - there’s no other appliances that I would have connected the other end to randomly like that. I imagine the other end is in the cabinet I keep the router in, and that the cable is not plugged into anything.
Oof - $100 is a little steep. Unfortunately, my laptop doesn’t have an ethernet port - I could just use that, and plug the other end into the router. And my desktop is a few feet too far away at the moment.
Both the wire and the receptacle have 8 points of contact. The wire says “general cable J 2001345 CMX outdoor-CMR C(ETL)US CMG 4PR”
I didn’t say anything about the connector, did I? I was referring to the cable.
I’m going to guess here that you’re speaking of your laptop as your testing tool, not as the computer in your OP that you wanted to connect to wired Ethernet. Your desktop is the device you mean in your OP.
In that case, yeah, it would be kind of silly to rearrange furniture or drag your desktop system over to where the cable is, just to test it. If you can’t find a cable tracer in your price range (and Google returns a lot of hits, so some shopping may be called for – just note that not all the cheap ones have RJ-11 and RJ-45 connector compatibility), maybe an inexpensive Ethernet switch (plus a length of pre-fabricated Ethernet cable) to “extend” over to where the desktop computer is, as well as give more Ethernet outlets in that area.
F’rinstance, I bought this exact Netgear 5-port switch explicitly to extend a short Ethernet cable over to where my desktop is. At Wal-Mart. In store. At about that price (<$30). And it works fine; I’ve used the other ports on the switch from time to time, like plugging my work laptop in to the house network to work from home.
Well, I looked into my cabinet. What I believe is the other end of this cord reveals a few things:
It’s a CAT5e cord - I didn’t have enough slack on the office room end to see the label.
The cabinet end of the cord has been cut, and the individual wires capped off in pairs with those little flat round caps.
There was a second cable in the cabinet that looked like it ran down into the basement. Where I found a rat’s nest of cat5e wiring, all with their ends cut off. Ugh.
Part of me feels like some of this could be really useful. I’ve been wanting to have a wifi extender in the basement, because it’s a pretty shitty connection. The other part of me doesn’t want to learn how to attach crimp connectors if it involves matching up each of those 8 tiny wires to the right contacts.
I’ve been doing it for more than a decade off-and-on, and I hate it. It’s gotten worse now that I’ve gotten into the bifocal age. My success rate at RJ-45 termination for Ethernet is about 75%; I have to redo often enough that I hate it.
Still, it’s hard to beat cables that are already run, if all you have to do is terminate them.
Another alterative, albeit more expensive and more of a project: install a patch box (once again, random Google return) in the basement and punch the wire ends (in the correct order) onto the patch punchdown connectors. Then you’ll have a bunch of Ethernet-wired RJ-45 ports to cable into.
Downside: not super cheap, also needs a 110 punchdown tool (more expense), a bit of a project. Upside: solve all your Ethernet cabling problems at once on the infrastructure level.
Disclaimer: I’ve definitely wanted to do this in my house. The fact that I haven’t yet in the >10 years I’ve owned the house, even though I’d like to and I have the expertise and tools, will tell you how daunting I consider the job. YMMV.
I hate to disagree with gnoitall, especially since I’ve not done this professionally, but …
You don’t have to connect the individual wires up to specific contacts, the connector does that for you. What you DO have to do is layout the wires in the proper order that matches the order of wires at the other end. Then, you shove that bundle of wires into your connector, which has little channels that guide each wire where it needs to be, and crimp it with the proper tool (which also presses the contacts into the proper wire all at once).
It is fine, fiddly work but easy with a few minutes (15-20, maybe) of practice. When I learned it in class, we were able to make commercial grade cables within a single lab session (starting from theoretical knowledge only). I’d strongly recommend buying a few feet of cable to practice on (possibly by buying a 6-foot pre-made cable and chopping the ends off. Not many places sell ethernet cable by the foot.). Connectors and boots are cheap (<$10 for a pack of 25, the smallest amount you can get), I got my crimping tool for <$20.
I’ll bet you can even find several youtube videos guiding you through the process.
Unless they untwist just a TEENY tiny bit while transferring them into the RJ plug before crimping. In which case, instead of greenwhite/green/orangewhite/blue/bluewhite/orange/brownwhite/brown, you get greenwhite/orangewhite/green/blue/bluewhite/orange/brownwhite/brown or something like that, and it doesn’t work, and you can’t tell because the colored stripe on the mostly-white wire is too fine to see through the distortion caused by the RJ plug’s plastic…When I said my success rate is 75%, the 25% is almost inevitably that.
As you say, not hard, but fiddly. Fiddly enough that I avoid it if I can help it.
The root of the fiddliness is that the conductors in the sheath of a CAT5 or CAT6 class cable are twisted in pairs (green is twisted with “white with green stripe”, or what I call above “greenwhite”.) And then the paired conductors are twisted (loosely) within the outer jacket. To use an RJ crimp plug, you have to trim back the outer jacket 10-12 mm (but no more or you compromise the pair twisting necessary for adequate shielding), separate the twisted pairs from each other, untwist the twisted pairs into individual wires, arrange them into a flat fan in the correct color order, remove residual bends left in the wires (from when they were twisted), compress the fan so that all 8 wires are still completely flat and co-planar and still in the correct order, but parallel with each other, trim the end of the flat parallel fan of wires to the same length, feed it (in the correct orientation!) into the crimp cavity of the jack, and crimp.
During any of the steps between “untwist” and “crimp”, the wires are trying their damnedest to get out of order, because ordering them correctly for the connection means you’re forcing them out of natural alignment with respect to how they’re still twisted down in the jacket.
So yeah. Fiddly as hell. Still, nothing in OP’s situation would be too hard, except maybe a desire to stick a fleet of RJ-45 plugs onto the unterminated rats-nest of wire in the basement. And in that case, the technically superior answer really is a patch panel. That’s the situation patch panels were invented for, and punching down a dozen or two 8-wire cables onto 110 termination blocks is VASTLY less fiddly than a dozen RJ-45 crimp-ons.
This thing is 70$. A tone generator and detector tool would really make identifying your mystery wires a lot easier. Maybe you could find a used one locally on craigslist?
Rather than crimping RJ-45 male ends on, punch them down into a handful of these:
There’s a video showing how they work on that page. I would recommend smaller side nippers that can cut the wire ends closer to the side of the jack than the scissors they used. You follow the stickers on the side to place each colour wire. There are two options, T568A or T568B. It doesn’t matter which you choose as long as both ends are the same.
Sometimes they come with a tiny plastic 110 punchdown tool included in a multiple jack kit. Or you can buy a slightly more sturdy one for 11$:
Then snap them into a surface mount box like this:
Would it be possible to get a terminated cable, tie it to the bad cable, and pull the new cable through by pulling the old cable out? Did that make sense? LOL
That way you’d be able to skip terminating anything. It’s a thought…
Yes, it can be done. Assuming that the old cable was not stapled or tied down when it was installed, and that it doesn’t go thru too many twists & turns & tight holes in 2x4’s. But it’s often worth a try.
I’m going to say about 90% of the difference is right there.
When I was 30 and RJ-45s were brand new, I rarely screwed one up. Bifocal age was now 10 years ago for me and it’s AMAZING how much smaller and badly marked those wires have gotten. And don’t get me started on the gray-on-gray fine print on every damn package of medicine. Why can’t anyone put bright enough lights in a damn room!
In other words, **dstarfire **old buddy: Don’t laugh; you’re next.
