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[Bald_Eagle1]

Update 07/04/2012:

Whilst awaiting the engineer for this morning's visit, I noticed my connection drop for a few minutes.

When the engineer (Tyrone) arrived, he explained that the purpose of his visit was to check for HR faults & to investigate dropping SNRM levels & occasional disconnections while the phone was in use.

He said that he hadn't been made aware of the long-standing issues, but he would be checking everything he could to try to get to the bottom of them (even though this wasn't officially a "Boost" visit).

What's a Boost visit, anyone?

He confirmed he had run a TDR & a FDR test from the cabinet (hence the disconnection) & both looked exactly as they should.

He did mention he had spotted a small amount of corrosion on the connection in the cabinet, which he dealt with while he was there.

From my home Tyrone ran an Equal Leg balance test & confirmed good balance (both legs around a value of 12).

He also ran a TDR test from my home (unfortunately I didn't get a photo), which showed a gradual tailing off of the plot until a large peak, which he confirmed as the cabinet itself.

There was a bit of an upward "hump" (I missed the distance, but was perhaps 1/3 of the way from my house to the cabinet). However, Tyrone said that was quite normal & to be expected.

He also mentioned the lack of any other evidence which more or less confirmed a lack of Aluminium cabling which would have shown on the graph.

One Exfo screen reported a line length of 1155m, which he said was a known "bug" (supposedly being looked into by Exfo) & then Tyrone showed me another screen which confirmed a line length of 834m from the cabinet, which is apparently accurate to within a few metres & is the "real" length.
This 834m ties in with a previous engineer's comment that my connection was roughly 820m & NOT THE 1100m OR SO THAT HAS BEEN MENTIONED ELSEWHERE.

Various other tests all passed, with the exception of the insulation test which failed.
Tyone checked the crocodile connections & about 5mm of the end of one of the pairs in the drop wire snapped off.
I suppose this could/would have been the cause of the dropping SNRM issue?



Tyrone also brought his laptop in, specially so we could have a look at Network Records & I now have confirmation of my connection's actual route.
The last section goes past my house (underground) to a joint chamber & then comes back to the pole opposite my house.
Pacing it out, that adds 60m to my D-side.
I wonder how how much sync speed & stability is lost in those 60m   


He had an Exfo tester, so I can't quite compare against any previous JDSU results from my connection.

These are the Exfo's stats (read out by Tyrone, but he said he was happy for me to take as many photos as I wished to):-

Code: [Select]


US DS
Actual Line Rate 6 24
Max Rate 6 33
Capacity 100% 75%
Noise Margin 6 9
Output 6.3 11.2
Loop Attenuation 7.9 31.6
Signal Attenuation 11 31.4

Now, the 31.6dB Loop Attenuation & 31.4dB Signal Attenuation (DS) bothered me a little as they have previously been reported as 23dB (from a JDSU) & when my connection was at its worst at 30.2dB.

However, as my connection was still capped by DLM at this stage, I thought I would wait until the modem was reconnected.
At least I would then be able to compare stats like-for-like.
The modem stats now show a slight reduction in DS attenuation (now more like the usual levels), which has allowed me to use some of the D2 frequency band again.

@BS, or any other engineers passing through:-

Is it usual to see large difference between Exfo & JDSU Attenuation readings?

Anyway, the HG612 was connected up & we had a look at its stats.
Sync speed was still at 24999k, so I asked Tyrone to phone through to get it re-set.

Watching SNRM while using the phone, resulted in a drop of only 0.2dB.
So it looks like replacing the master socket's filtered parts and/or the end of the drop wire cable snapping off and/or sorting out the slight corrosion on the connection at the cabinet has resolved the recent dropping SNRM & occasional disconnection.

On leaving, Tyrone said he would phone through from his van to get DLM re-set.

I did see a re-sync, with a resulting speed of 31115 k DS & 5795 k US.
That was a little disappointing as the previous re-set gave me a DS sync speed of 35322 k DS & 6372 k US.

A few minutes later, the phone went dead & the connection dropped.

Oh, no!
On checking, Tyrones van had gone.

5 minutes later, the phone came back on & the connection was restored, a tiny increase, but still disappointing at 31251 k DS & 5807 k US.

Tyrone then phoned, saying he had been sent to check that everything at the cabinet was 100% correct, so that was what had caused the disconnection.

He also mentioned that while he was on the phone to OMC (I think that what he called it), the gentleman at the other end had told him there was a long history of instability & low speed on my connection & that they believe there is still another underlying issue as I am not too far from the cabinet.

He told OMC that 79Mb was showing at the cabinet (I'm on Plusnet's 80Mb/20Mb trials at the moment) & they both agreed that I should be seeing somewhat better speeds & certainly more stability over the 834m.

I'm not sure how this has been left, so I will be contacting Plusnet to find out.

While he was still at my house, Tyrone mentioned the slight possibility of REIN being the cause of my connection's issues, but looking at my graphs, he more or less ruled it out as there was no discernible pattern to the frequent but irregularly timed disconnections/errors etc.

Without any prompting, Tyrone said he would provide fully detailed notes from today's visit.



I wish to record that Tyrone was the most polite, helpful & informative of engineers, talking me through everything he was doing & showing a genuine interest in anything I mentioned & showed him.
He seemed really interested in the unlocked modem's GUI & mentioned that enginners were only shown that during their initial fibre training session.

He even held out his hand for a handshake on arrival & again on his departure 

[burakkucat]

You have clearly been visited by a most helpful and knowledgeable Openreach employee.   

The saga continues . . . So we shall watch this space, with interest. 

[ At a personal level, if there are any sketches / maps / photographs / whatnots / etc as a result of Tyrone's visit, I trust that an e-mail message will be on its way (to The Cattery) as a carrier of the same.    ]

[renluop]

So it's Tyrone power that's done it!

Note for those of tenderer years only

[Bald_Eagle1]

[ At a personal level, if there are any sketches / maps / photographs / whatnots / etc as a result of Tyrone's visit, I trust that an e-mail message will be on its way (to The Cattery) as a carrier of the same.    ]

TBH, I only have one photo (attached).

Regretfully I didn't take one of the TDR trace that may have been useful for experienced users to comment on, but I have attached a very rough sketch of its appearance.

I simply wrote down the important line length & connection stats (I can see my own stats for comparison of any changes anyway):-


Just before the visit:-

Code: [Select]

Max: Upstream rate = 6474 Kbps, Downstream rate = 28080 Kbps
Path: 0, Upstream rate = 6254 Kbps, Downstream rate = 24999 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6474 kbps         28080 kbps
Actual Aggregate Tx Power:        6.2 dBm          10.8 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.3 53.8 64.0   N/A 22.0 64.0 0.1
Signal Attenuation(dB): 11.0 52.7   N/A   N/A 22.0   N/A   N/A
        SNR Margin(dB): 6.3 6.3   N/A   N/A 8.9   N/A   N/A
         TX Power(dBm): -4.2 5.8   N/A   N/A 10.8   N/A   N/A



Engineer finished - awaiting DLM re-set:-

Code: [Select]

Max: Upstream rate = 5836 Kbps, Downstream rate = 31484 Kbps
Path: 0, Upstream rate = 5836 Kbps, Downstream rate = 24999 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       5836 kbps         31484 kbps
Actual Aggregate Tx Power:        6.3 dBm          11.4 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.1 53.3 65.1   N/A 21.9 63.6 0.1
Signal Attenuation(dB): 9.4 52.6   N/A   N/A 21.9 63.6   N/A
        SNR Margin(dB): 6.1 5.9   N/A   N/A 10.6 10.6   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.9 2.1   N/A



At the end of the visit (DLM Re-set):-

Code: [Select]

Max: Upstream rate = 5731 Kbps, Downstream rate = 31232 Kbps
Path: 0, Upstream rate = 5768 Kbps, Downstream rate = 31048 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       5731 kbps         31232 kbps
Actual Aggregate Tx Power:        6.3 dBm          12.0 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 53.4 64.7   N/A 21.9 63.6 0.1
Signal Attenuation(dB): 9.7 52.6   N/A   N/A 21.9 63.6   N/A
        SNR Margin(dB): 6.1 6.1   N/A   N/A 6.1 6.3   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.8 5.3   N/A



DLM Re-set of 9th March - highest sync speed since July 2011:-

Code: [Select]

Max: Upstream rate = 6376 Kbps, Downstream rate = 35864 Kbps
Path: 0, Upstream rate = 6372 Kbps, Downstream rate = 35322 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3939)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207)
DS: (32,859) (1216,1963)
       VDSL Port Details       Upstream        Downstream
Attainable Net Data Rate:       6376 kbps         35864 kbps
Actual Aggregate Tx Power:        6.2 dBm          12.2 dBm
============================================================================
  VDSL Band Status        U0      U1      U2      U3      D1      D2      D3
  Line Attenuation(dB): 8.2 53.0 64.1   N/A 21.6 63.2 0.1
Signal Attenuation(dB): 14.4 52.5   N/A   N/A 21.6 63.2   N/A
        SNR Margin(dB): 6.0 6.1   N/A   N/A 6.3 6.4   N/A
         TX Power(dBm): -4.3 5.8   N/A   N/A 10.9 6.4   N/A


The changes are small, but appear to make enough difference to dictate which band plan(s) can be used (or not) & make a few Mb difference to sync speed.

Due to the recent disconnections/SNRM dropping issue, the stats from just before the visit are from when DLM had capped my sync speed at 24999k.



[attachment deleted by admin]

[Bald_Eagle1]

So it's Tyrone power that's done it!

 

[Bald_Eagle1]

Hmmm,

I have just discovered that my connection had re-synced while I was typing my previous message.
It had been up for just over 18 hours.

I can't see any reason for this re-sync in my stats (low error counts, SNRM still at 4.9dB from its night time reduction) & no electrical equipment was turned on or off in my house at the time.

I didn't notice whether or not the street light about 3m from the pole where my drop wire starts switched off at that time.

We did discuss that particular pole & street light during yesterday's visit, along with coffin lids & patch cable tricks etc. (thanks BS - they call them coffin lids in Oldham too) & ruled it out as a potential REIN source as the frequent disconnections have not previously coincided with street light switching on & off times.



[attachment deleted by admin]

[burakkucat]

So it's Tyrone power that's done it!

Note for those of tenderer years only

I was wondering who would be the first to make such an observation! 

[waltergmw]

@ BS,

If you are able to identify Tyrone, I am sure that BE1 and every Kitz observer would like you to pass on our most grateful thanks and hearty congratulations to Tyrone's supervisor / coach.

This encounter must surely illustrate that only with full co-operation between the EU and O/R staff, and an unlocked modem, that these types of anomaly can be effectively cured as we all recognise what a horrible needle in a hay stack we are chasing.

Kind regards,
Walter

[Bald_Eagle1]

@ BS,

If you are able to identify Tyrone, I am sure that BE1 and every Kitz observer would like you to pass on our most grateful thanks and hearty congratulations to Tyrone's supervisor / coach.

FWIW, Tyrone started as an apprentice with BT & he thinks the guy who trained him was the very same guy who restored my 35Mb just a few weeks ago.

That was only a site visit to get DLM reset, but still.................

[Black Sheep]

Hi, I have suprisingly managed to track down Tyrone's details. Thought it would be a 'needle in a haystack' task, with just having the first name and him being under a completely seperate Operational Unit.

Anyhows, if BE wishes to pass on his regards, I can supply the specific job number (Information that is in the public domain and could be requested by BE from his ISP) via PM, and BE would then have to approcah his ISP and request that they pass on the regards on his behalf. I'm not going to start dishing out engineers personal info on a public forum PM or otherwise i'm afraid, however good the intentions might be.
I'm sure you'll appreciate it could have all sorts of repercussions. 

[covlad1987]

Well, I've half-succeeded in my quest. 

The picture of the Box Conn is exactly the one we use, as mooted previously. However, the picture of the module is not what we use, and is only to give a rough idea of what they look like.
Whereby in the picture both sides of the module are 'Screw-fix', the ones we use are 'Push-fix' for the UG connection. It is this that causes the issues with lower than 0.5mm poundage cable, as there is a bit of a 'spring back' on the connector regardless of how hard one pushes.

Hope this gives a better insight as to what I'm waffling on about ??

thats what on the pole out side my house lol

[Bald_Eagle1]

Thanks for that BS.

Plusnet's Alex has this morning confirmed he has read this thread's report of the visit & I have added suitable comments to the Plusnet fault ticket system anyway, so communicating job details etc. via PM won't be necessary.

Cheers,

Paul.

[Black Sheep]

Cheers BE. Have PM'd you anyway, regarding the benefits to the engineer of good EU feedback. No other details have been sent, as PNET have all the neccessary information as you state. 

[les-70]

 In case it is of any interest the document below is helpful for understanding TDR traces. See in particular the examples at the end .  The hump in your sketch look bit like a weak HR point in the cable??.  The big feature at the end is presumably the cable end.

 http://documents.exfo.com/appnotes/anote168-ang.pdf

  Also

 http://myaccount.flukenetworks.com/fnet/en-us/StreamIt?Document=9821102

   and no doubt others

[burakkucat]

The big feature at the end is presumably the cable end.

Er, no.    That is the FTTC DSLAM, which shows as a "now you see me, now you don't" "beacon" at 0.5 Hz. The boffins at "Grimbledon Down" specified that should be present, so as to allow the most junior of Field Service Operatives to be able to identify something, with certainty, in the TDR trace of a VDSL2 copper pair.