Kitz Forum
Broadband Related => FTTC and FTTP Issues => Topic started by: gazaai on June 05, 2017, 11:55:35 PM
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Hi all, earlier this evening I spotted an open reach engineer climb the pole outside my home and ever since my line stats have went terrible. Unfortunately I don't think there is anything I can do at this point :-\. Although what do you think has happened here?
(https://i.gyazo.com/bd08cee73b36a921a201e13cdc185987.png)
Thanks
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That 1dB jitter is familiar to what a couple of us on ECI cabs have experienced.
Out of interest you could try switching of your modem for a couple of hours. Sometimes (but not always) that can clear the jitter.
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That 1dB jitter is familiar to what a couple of us on ECI cabs have experienced.
Out of interest you could try switching of your modem for a couple of hours. Sometimes (but not always) that can clear the jitter.
Ok well it seems to have cleared itself for now anyway but has lost a fair bit of SNR. If the jitter returns I will turn off the modem for a couple of hours. Thanks
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. . . it seems to have cleared itself for now anyway but has lost a fair bit of SNR. If the jitter returns I will turn off the modem for a couple of hours.
The best time for performing the "power off, allow the circuit to relax procedure" would be overnight.
A small correction to your statement; it is not SNR that you have lost but SNRM. There is a significant difference between the two quantities.
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As B*cat quite rightly says SNRMargin (http://www.kitz.co.uk/adsl/linestats.htm#SNR_Margin) and SNR (http://www.kitz.co.uk/adsl/linestats.htm#SNR) are not the same thing, they do have some type of correlation. I would not be surprised if the line has also lost a similar amount of true SNR.
Obviously I dont know for certain what caused this, but one thought is that the engineer could have been doing some sort of re-wiring that could have shifted a neighbouring pair within the same bundle. This could then introduce crosstalk on to gazaai's line. Note how things were better for a short while (possibly whilst the other line was disconnected. If he reconnected to a pair more adjacent to Gazaai's, it could possibly cause more crosstalk than the previous pair did.
I really do wish I knew what causes that jitter. All that I know is that on my line it can sometimes happen after remote sync if I come back up before my cross-talker, or Ive also seen it happen a couple of times after a crosstalker resync.
Although GaZaai says its now settled, but it does look like it has only done so after some remote action (resync) by one of his crosstalkers and he has lost even a bit more SNRm