ADSL Fluctuating margin/transmit power

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codyc1515

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Topic # 98683 4-Mar-2012 02:57

I appear to be encountering something strange with my ADSL connection at home. I do understand that it is far from the exchange but it never used to be like this. The Downstream Margin varys anywhere 6-12db and the Upstream Transmit Power varies between 20-21db. I tried with both ADSL1 and ADSL2+. What might cause this to happen? I read on another local forum that a cordless phone could cause this interference but that does not sound correct.

DSL Status: Connected
DSL Modulation Mode: G.dmt
DSL Path Mode: Interleaved
Downstream Rate: 2592 kbps
Upstream Rate: 544 kbps
Downstream Margin: 0 db
Upstream Margin: 12 db
Downstream Line Attenuation: 63 db
Upstream Line Attenuation: 15.5 db
Downstream Transmit Power: 12 db
Upstream Transmit Power: 4 db

DSL Status: Connected
DSL Modulation Mode: ADSL2+
DSL Path Mode: Interleaved
Downstream Rate: 1722 kbps
Upstream Rate: 661 kbps
Downstream Margin: 11 db
Upstream Margin: 13 db
Downstream Line Attenuation: 63 db
Upstream Line Attenuation: 16.5 db
Downstream Transmit Power: 12 db
Upstream Transmit Power: 20 db

cyril7

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Reply # 590096 4-Mar-2012 09:05

Hi, as you already acknowledge in your opening statement at 7km or so you are using the product outside of its specified operating limit, so you must expect variable results and not to ever expect a resolution. Its like telling your mechanic that you Corolla keeps overheating and loosing power for long periods when crossing the nullibour plains at 180km/hr hour after hour in the mid day sun, its just not going to get a decent reply as it was never designed for that and how it behaves over the normal limits well who knows as that was not part of the design brief.

Might I also suggest that the 7-9km of cable are a bit damp at the moment, this can cause issues if water is getting in our some joints are not the most water tight.

Oh, and 1dB variation in Tx power is nothing, its not even a 10% change. And the noise margin, as I say water in a section of cable can cause crosstalk issues, which appears as noise to the modem.

Cyril

webwat

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Reply # 590385 5-Mar-2012 08:06

At 63 db you are lucky to get anything at all, but do you have central filter/splitter installed? Thats going to at least minimise house wiring issues. Test a different modem just to be sure thats not the problem.

Qualified in business, certified in fibre, stuck in copper, have to keep going ^_^

johnr

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Reply # 590387 5-Mar-2012 08:09

I have already gone over this with you, You are too far from the exchange / cabinet you have also brought this up in another thread on Geekzone and it was covered over then as well

John

codyc1515

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Reply # 590461 5-Mar-2012 10:22

johnr: I have already gone over this with you, You are too far from the exchange / cabinet you have also brought this up in another thread on Geekzone and it was covered over then as well

John

I don't believe this was the same issue.

johnr

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Reply # 590465 5-Mar-2012 10:25

codyc1515:
johnr: I have already gone over this with you, You are too far from the exchange / cabinet you have also brought this up in another thread on Geekzone and it was covered over then as well

John

I don't believe this was the same issue.

You are still speaking of ADSL issues on the end of 7km of copper

cyril7

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Reply # 590469 5-Mar-2012 10:31

As mentioned by me earlier, use a product out of its normal operating range and you can expect all manner of variable results with no real chance of resolution. All the threads I have seen have shown this hallmark, unstable, random variations in connection and performance.

Cyril

codyc1515

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Reply # 590587 5-Mar-2012 12:37

Yes but this was not always the case. Attenuation on the line has increased by about 10db over 3 months. This is not normal.

cyril7

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Reply # 590607 5-Mar-2012 12:48

Hi, so its gone from 53dB to 63dB, no not normal, but whats normal when its being used out of spec. As of recent weeks Chorus have changed the rules and I think would refuse to connect you on 53dB let alone 63, why, because its not stable.

Cyril

codyc1515

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Reply # 590609 5-Mar-2012 12:49

cyril7: Hi, so its gone from 53dB to 63dB, no not normal, but whats normal when its being used out of spec. As of recent weeks Chorus have changed the rules and I think would refuse to connect you on 53dB let alone 63, why, because its not stable.

Cyril

If by unstable you mean disconnecting this is not the case. I can easily do 16GB over a day without the download failing.

cyril7

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Reply # 590621 5-Mar-2012 13:09

Hi, no unstable means it changes its apparent performance over time, could be disconnecting could just be sync rate changes as noise profile moves about. As I said once over 50dB the stability and characteristic of the connection is out of range for any predicted profile, end result anything can and will happen and no one will be prepared to explain or support it.

Cyril

codyc1515

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Reply # 590625 5-Mar-2012 13:11

cyril7: Hi, no unstable means it changes its apparent performance over time, could be disconnecting could just be sync rate changes as noise profile moves about. As I said once over 50dB the stability and characteristic of the connection is out of range for any predicted profile, end result anything can and will happen and no one will be prepared to explain or support it.

Cyril

Well I rung twice now about it and they said they would send someone out from Chorus. The guy never called/txted as they said Chorus should have in advance but I noticed that the ETP underneath the house has been moved. So maybe they did come? I got txt saying that the ticket was closed and that was about it.

mercutio

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Reply # 590637 5-Mar-2012 13:29

cyril7: Hi, so its gone from 53dB to 63dB, no not normal, but whats normal when its being used out of spec. As of recent weeks Chorus have changed the rules and I think would refuse to connect you on 53dB let alone 63, why, because its not stable.

Cyril

at that distance that's about the difference when there's a new cabinet nearer you - you get placed through the cabinet for a couple of weeks, and still run back to the exchange.

you could very well have had 2 megabit to 1 megabit drop, or other severe issues at that distance if this was the case.

if you're on an isp such as slingshot with llu, you may have to request to be put onto chorus equipment if there is a cabinet nearby.

codyc1515

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Reply # 590671 5-Mar-2012 14:07

mercutio:
cyril7: Hi, so its gone from 53dB to 63dB, no not normal, but whats normal when its being used out of spec. As of recent weeks Chorus have changed the rules and I think would refuse to connect you on 53dB let alone 63, why, because its not stable.

Cyril

at that distance that's about the difference when there's a new cabinet nearer you - you get placed through the cabinet for a couple of weeks, and still run back to the exchange.

you could very well have had 2 megabit to 1 megabit drop, or other severe issues at that distance if this was the case.

if you're on an isp such as slingshot with llu, you may have to request to be put onto chorus equipment if there is a cabinet nearby.

The guy initially said I was on a cabinet I then said that could not be correct as, as far as I am aware, there are no cabinets out here. Although I can now get ADSL2+ even though the exchange says it is not capable on the Chorus website. I am on Vodafone (not Slingshot) if that helps.