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[burakkucat]

I am unaware of how the metallic pathway will selectively penalise a VDSL2 based service (over an approximate distance of 1 km) more than an ADSL2+ based service (over the same approximate 1 km distance plus a further approximate 2 km distance)! 

[Weaver]

Aluminum has about 60 percent of the conductivity of copper - so, other things being equal, which I don't know about, would have to ask Black Sheep, it ought to make a difference to attenuation surely?

[burakkucat]

You are quite correct in that respect.

We could also consider that aluminium, a highly reactive, amphoteric, metal, which pasivates rapidly in the presence of oxygen, will show greater attenuation as the frequency is raised due to the skin effect.

But in renluop's case, the D-side length of (presumed) aluminium cable remains the same. Hence my earlier musing . . .

[Ronski]

Aluminium certainly does make a difference. Our estate was built in the seventies and we highly suspect there is aluminium in the circuit here. We're about 450 -500 meters and my sync has always been on the low side, down stream ranging from 60 at best very briefly to as low as 38 but generally been in the forties, upstream started out at 12 and has gradually dropped to at the lowest point just under 6, but has fluctuated between 6 & 8 recently. I was first on the cab in 2012, which is unfortunately an ECI which no doubt also played it's part in the low speeds.

[renluop]

@Ronski
How good was your old steam connection compared with BT estimates?

[Chrysalis]

if equal size ali has worse loop loss, but if e.g. 0.6 ali compared to 0.2 copper, it wouldnt be inferior.

Another problem with ali is on the joints.

I think the most plausible explanation for your underwhelming sync speed is crosstalk, this can be to a degree be verified if you posted a QLN graph.

[Ronski]

I got FTTC in August 2012, back then the estimates were not very accurate, I think mine were 66/12 but can't be sure. The estimates dropped as they gathered data from lines.

[renluop]

Chrys, I would, if i could, but am presently using the HubOne. Therefore here is one from the Billion just before I swapped. Also here is the GEA Test, in case that's of some value.

Ronski I was just curious, if, like me, your ADSL was better than expected.

[j0hn]

As I expected it to be, the DLM profile listed on the GEA test is way out of date.
It shows the line as being interleaved, with no G.INP.
We know this to be incorrect.

[Ronski]

Ronski I was just curious, if, like me, your ADSL was better than expected.

I think it was, but so long ago now can't really remember. The top end of my current estimate is what I used get IIRC

[NewtronStar]

ADSL speeds back in 2011 was dependent on whiich ISP was being used at the time freeserve/wanadoo/orange 5Mbps , TalkTalk 4.5 Mbps , BT 6.1 Mbps the total loop length from premises to the exchange is 1.9km

The D-side on FTTC cabinet to premises is 1KM if that helps your nerves 

[renluop]

NS, you talking about yourself? At 1 km D side what do you get? I did mention that I thought route taken to our and nearby houses could have taken a different route, as houses were on last phase. (We have flues not chimneys. There's also a SCP at the estate entrance, so were we teed off from there and taken round the houses to serve into the country with us by the way? (musing again).

I await Chrys' opinion of QLN and crosstalk.

Had a speed reduction this evening to 19. My own blessed fault, it was my tidying the cable cats' cradle of wiring round my tower extension lead, that did it!

[NewtronStar]

Definitely wait for Chrysalis he is the best broadband stats analyzer on these forums, hope all goes well during OR engineer visit tomorrow.

[renluop]

10th Thursday.

[NewtronStar]

Engineer is booked for Wednesday p.m.

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