1 RJ45 to 4 BT converter?

While I haven't heard of such a device, there's no reason why you couldn't build one. You can buy boxes that can hold 4 keystone jacks or similar. You'd populate them with appropriate phone jacks and run some 4 pair wire to an RJ45 plug, which can connect to the jack.

Reply to
James Knott
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I am a technical manager at a company that offers serviced office space. We have our own PABX and network systems and the building is flood-wired with CAT5 terminated with female RJ45 wall sockets (pretty common). I just registered to ask this question.

Since CAT5 cabling has 4 pairs and since a standard phone connection only uses 2 pairs, is there a converter available that would allow me to plug 4 telephone cables into 1 RJ45 socket? I would obviously plug another into the socket in the cabinet. We have run out of ports in 1 suite and this would allow me to run 4 telephone lines down 1 CAT5 cable, saving me the job of running more cables to the 5th floor.

If such a converter is not available on the market, is there any reason why I shouldn't build my own?



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Reply to
Sam Tolton

Although there is nothing that stops you from making your own out of an

8P8C plug, a short piece of cable, 4-port surface mount box and 4 8P8C jacks, there are products on the market that do just what you need. One example is Black Box'es FM825 adapter. I'm pretty sure plenty other people have the same type adapter, too. I just had Black Box catalog sitting on top of the pile ;-)

Anyways, be careful with your 1-pair per phone assumption. You've mentioned a PBX, and plenty times you need actually 2 pairs per extension. In this case you'll have to worry about the pinout the adapter supports: T568A or T568B or USOC. But if you are sure yours are 1-pair phones, it's an easy job and the above mentioned adapter will do it just fine.

Good luck!

Reply to

In article , Sam Tolton writes

Google on Coolport.. Depends on the type of telephone system you have as to which pair(s) are used, so which you can use.

No reason whatsoever, have done this in the past.

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Phil Partridge snipped-for-privacy@pebbleGRIT.demon.co.uk Remove the grit to reply

Reply to
Phil Partridge

Back in the day, and on our side of the pond, we used a MERLIN splitter cable, which took 4 RJ-11's to a 568B 8-pin plug.

Hubbell still shows it in the catalog, but IIRC it's pretty pricey, like about $12-15 for a 12-foot cable. p/n BMD04p26712DE

Carl Navarro

Reply to
Carl Navarro

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