RJ11 in RJ45 Jack.

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So I just finished putting network drops in my new house. I wired everything B and it all runs to a patch panel downstairs and everything works fine. I tested all of the drops as well. I am unable to find a clear answer on my question. From what I have read A will let you use RJ45 to carry RJ11. Is this doable with T568B? Do I need to rewire anything to be able to use one of my RJ45 drops to carry a phone line?
 
I usually do all drops A to A, are you going B to B or B to A? I would think B to B would work fine since the pin outs on each end would end up the same.
 
They are B to B. I just tried one here and I didn't get any dialtone. Maybe the contacts aren't lining up? I am using a two wire phone cable too... maybe if I switch to a 4.
 
It shouldn't matter. Make sure on both ends you use the center pair (pin /4 / 5 ) for line one and pin 3/6 for line 2.

Also, personally, I like to make RJ45 to 4P4C cables. Because what I've seen if you plug in a 4P connector to an RJ45 jack sometimes the outer pairs on the jack get bend (these correspond to the area of plastic edge adjacent to the contacts on the plug)
 
Assuming you only have one phone line, either A or B will work. The white/blue pair is what you need to be using (pins 4 and 5 on an 8 pin jack)
 
athlon1.2 said:
It shouldn't matter. Make sure on both ends you use the center pair (pin /4 / 5 ) for line one and pin 3/6 for line 2.

Also, personally, I like to make RJ45 to 4P4C cables. Because what I've seen if you plug in a 4P connector to an RJ45 jack sometimes the outer pairs on the jack get bend (these correspond to the area of plastic edge adjacent to the contacts on the plug)
Click to expand...

Hmm. I was just thinking of doing this. Crimp an RJ45 end on one end and a RJ11 on another end of a piece of Cat6.
 
Ok, I'm going to just crimp RJ11 on one end of a short piece of CAT5 and crimp RJ45 on the other end. What would the pinout look like? I would make two of these, one on the end of the patch panel and one on the drop side. Basically a converter cable. I'm looking at http://www.lanshack.com/wire_phone_jack.aspx and trying to figure it out. Do I wire one end 568B and the other end like that diagram shows?
 
Be careful about putting RJ11 connectors into a RJ45 jack. The RJ11 jack only has 4 conductors, so the outer 2 sets of conductors on the RJ45 jack will be pressed back extra far by the plastic edges of the RJ11 jack. If you try and use the RJ45 again for a data connection, those outer 4 conductors may be bent too far back to make proper conduct again.
 
My pinouts on my adapters are as follows:

RJ45 End:

Greenwhite
Green
Orangewhite
Blue
Bluewhite
Orange
Brownwhite
Brown


RJ11:

Green
Orange
Whiteblue
Blue
Orangewhite
Greenwhite

(This is looking at the connector with the clip facing down on both ends)

Does this look correct? I have no way of testing them till tonight when I get home.
 
We use RJ45 patch panels for our phone system (soho type network, so we mix phone/data on patch panels) and haven't had a problem with RJ11 jacks in them in the last 10 years or so, maybe I've just been lucky, but I always thought the ports were made so we could mix and match RJ11/RJ45 without physical damage to the port/jack.
 
Some of the better jacks are designed so that if you do put a 4 pin plug in an 8 pin jack, they won't be harmed by it.
I still don't recommend it, just make an adapter cord like described above.
 
So I made up the adapters here at work this morning and tried them here at noon. They work awesome. Now I can keep my HP terminal down with the patch panel and my majicjack running on there and wire in phones to the data drops. Everything nice and neat with the patch panel. Now I have to see if I can use the same adapters to bring my VDSL connection through the patch panel as well. I'm not sure exactly what pairs the DSL is on. If it's the green and red I'll be good, but it might be the black and yellow. It's a dry DSL install too.
 
If the DSL is its own dry pair coming in from the NID then it's most likely on the black/yellow.
If you don't have any other POTS lines then it's probably on the red/green.

Glad you got it working!
 
Jaffa Cakes! said:
We use RJ45 patch panels for our phone system (soho type network, so we mix phone/data on patch panels) and haven't had a problem with RJ11 jacks in them in the last 10 years or so, maybe I've just been lucky, but I always thought the ports were made so we could mix and match RJ11/RJ45 without physical damage to the port/jack.
Click to expand...

Apparently the problem is more prevalent with newer cat6 panels.
 
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