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Ptt 278 used as ethernet

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brupala Posted messages 111146 Registration date   Status Member Last intervention   -
Hello,
I have an old network that is in PTT 278 4 pairs and I would like to know the maximum speed that this line (less than 30 meters) can reach to convert it to Ethernet. I don't see the difference between PTT 298 4 pairs and PTT 278 4 pairs (the diameter?)
Thank you for your answers.

2 answers

  1.
    jee pee Posted messages 9441 Registration date   Status Moderator Last intervention   9 981
     
    Hello,

    The 298 has 4 twisted pairs, the 278 is generally not twisted, so 8 wires. The twisted pair affects the quality, with 30m, it needs to be tested to see if it will work in 278. There are installations where the ptt278 allows Ethernet to circulate.

    Note that on a single-strand cable, you connect 2 female RJ45 connectors at each end: https://forums.commentcamarche.net/forum/affich-37585049-compatibilite-cables-et-prises-rj45

    Best regards
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  2. brupala Posted messages 111146 Registration date   Status Member Last intervention   14 448
     
    Hi,
    the (very) old CAT3 PTT 278 is for telephony exclusively, the pairs are twisted but very little, I might be wrong, but roughly speaking it's about one turn every 10cm.
    this limits it to a speed of 10Mbit/s

    --
    and ... There you go!
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