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Re: [vox-tech] Carrying telephone signal over ethernet
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Re: [vox-tech] Carrying telephone signal over ethernet

I could be wrong, but I believe that Cat5 uses all 4 *pairs* of wires, and not just 4 wires. Maybe that's only for full duplex....

IIRC, Cat3 (i.e. 10baseT) was designed with phone compatibility in mind.. and leaves the center pair unvired, so that it's compatible with the older rj11 plugs in a very direct way. You can plug an old rj11 plug into a rj45 jack, and I think that the original conception was that every jack would carry both phone and ehternet, and you could plug either computer or phone in as needed.

-- Mitch

On Thursday, Mar 18, 2004, at 13:44 US/Pacific, Mark K. Kim wrote:

So my dad's workroom has no phone line, believe it or not. I do have a
phone line in my room, though, and we got a ethernet line between our two
rooms. Since 10baseT uses only 4 of the 8 lines on the cat5 cable I'd
like to use the unused lines to carry the voice signal. I know cat5 was
designed to do this (middle two lines are open), and I've done it before
with custom adapters (messy), but I can't find any splitter online that
does this. Anyone know where I can get a pair? What's it called?



Mark K. Kim
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