Aluminium Telephone Line

[#1]

I just thought I'd start a topic on the dreadful aluminium telephone lines that some of us suffer. Not a PN issue.

Every time I read a broadband article they always mention 'copper' to the house, I wish, never ally.

My FTTC speed, according to the engineer, was pushing out 58Mbps from the cabinet. That was when I was on a 40Mbps connection. That was reduced by 800 metres of aluminium to 23Mbps at my router.

Since the change to 55/10 I've been getting 24Mbps. Still quite pathetic considering.

From what I've read, during the 70's and 80's, aluminium was the norm for new estates so there must be a lot of us suffering.

[#2]

When I had a new cable run put in for IDSN about 13 years ago the engineer replaced the drop line for my phone which was aluminium with copper at the same time that he replaced the run from the DP to the house.

I would have thought that if the speed you are getting is impacted to the point at which its below the threshold then they should replace the aluminum where they can......

[#3]

I am not sure I understand the engineer stating that 58 Mbps was being pushed out from the cabinet, and that was reduced by 800 metres of Aluminium to 23 Mbps. That isn't how VDSL works. The speed is negotiated based on the entire link, from cabinet to end user modem. The cabinet is capable of 'pushing out' the full product speed (80/55/40 etc). But in reality, the line from the cabinet to the end user modem is what dictates the overall speed. I don't think there is any doubt that aluminium is worse than copper for VDSL connections, so you will fare worse over an aluminium connection.

A typical graph of vdsl speed against line length shows about a speed of 33 Mbps for an 800 metre line length. So if that line length is correct, you could be losing about 9 Mbps to aluminium (versus copper). Although there could be other reasons that would cause a slower connection.

[#4]

I'm over 700 from the cab (BT estimate of 878.7) .. the cables go past my house to a DP and come back for the last 150 foot or so in the air. I know I was on aluminium from the junction on the house to the master socket and that was replaced when they did the new run from the pole. So I assume that that would be aluminium as well, but not sure if that means the run from the cab at the bottom of the street is or not.

After getting my master socket (a first gen ADSL one) replaced at the weekend I'm seeing downloads of nearly 40Mb (and 7 up)... before it was 32 Down and 7 up. 

[#5]

I have read that the MK3 master socket has better filtering inside, which may account for the improvement. Nowadays, separate micro filters are used for new provisions (same as for ADSL really), which is a shame, because to get the best speeds, you really should be filtering at the master socket. Even if the modem is plugged directly into a microfilter attached to the master socket (and assuming you have extension wiring in the house), a MK3 socket will still be better, because it prevents the VDSL2 signal from being transmitted around all your extension wiring.

VDSL2 operates at higher frequencies than ADSL which makes it more prone to losses in wiring, which is why it is preferable to terminate the VDSL signal at the master socket (i.e. filter there) rather than having it going around all the extension wiring.

In my case, I ran a CAT6 ethernet cable from the MK3 master socket to my office (using only 1 pair of the cable). I chose CAT6 over regular phone cable just because it has tightly twisted pairs.

[#6]

I've got a 5c master socket with the OR MK4 front plate - its a bit bulky but.....

[#7]

There's fors and againsts these MK3 type sockets. If they go faulty, it's not as easy as popping a new microfilter in, what most users think is the test point isn't actually the true test point, from experience when using the Sky BB diagnostic tool it fails when testing as it doesn't 'see' the socket as a microfilter, it's common for ISP's to charge us for it's replacement even though it should have (and has in my case) been installed by BTO or (in my case) their contractor.

I'm not knocking them, as I'm currently using one

From reading about, some MK4's have been known to fail due to corrosion on it's terminals, IIRC these were revised on later models...?

The bit above in this post may help users in the future, hence the reason for posting.

Anyway, I'm on around 800+metres of aluminium too

From My Portal:
Estimated line speed: 32Mb (This may vary between 24Mb and 32.4Mb) - Checked on 2016-12-02 16:55:52
Current line speed: 30.4Mb

From the PNH1:
Data rate: 2001/23503
Maximum data rate: 2779/22984

BTw Performance Test:
Download Speed (Mbps): 21.94 - Max Achievable Speed 22.75 Mbps
Upload Speed (Mbps): 1.81 - Max Achievable Speed 2 Mbps
Ping Latency(ms): 21.38
IP Profile for your line is - 22.75 Mbps
Upstream Rate IP profile on your line is - 2 Mbps

[#8]

I wasn't even aware a MK4 socket was available. It does look bulkier than the MK3 but that may just be deceptive based on the photos I saw.

I wonder if there are any technical improvements to the filter. I would have thought it would be difficult to offer much improvement to what is effectively a fairly simple passive filter.

[#9]

---

@Kremmen wrote:

I just thought I'd start a topic on the dreadful aluminium telephone lines that some of us suffer.

As a customer, I can empathise with that, being restricted at my previous property to 2Mb/s sync until a long length of Ali was replaced on the D side - whereupon sync increased to 5Mb/s. That was an incidental benefit - the Ali was replaced because everyone on that D side was suffering two or three losses of telephony per year because of corroded joints where the Ali and copper met.

As an ex-BT engineer, I remember that we at the sharp end always said, before its introduction, that using Ali was a short-termist, stupid idea... 

[#10]

The way I understand it the MK4 was brought out because the new Master Socket 5C does not use screws on the front face plate. Once you have pulled the face plate off you just push the MK4 into place until it clicks in, doesn't look like their are any improvements over the MK3 in terms of filtering. Of course those with the older NTE5 sockets will still have to use the MK3 as the MK4 will not be compatible unless they upgrade to the new Master Socet 5C.

[#11]

Well I won't be upgrading from the MK3 anytime soon. I actually don't like the styling of the MK4 compared to the MK3, but that is a minor issue. If there was evidence the MK4 performed better, I would consider changing irrespective of the styling.

[#12]

Before the socket replacement (and a line reset):

Parameters	MIN	MAX	AVG
Down Stream Line Rate	35.0 Mbps	35.0 Mbps	35.0 Mbps
Up Stream Line Rate	7.8 Mbps	7.8 Mbps	7.8 Mbps
Up Time	899.0 Sec	900.0 Sec	899.9 Sec
Retrains	0.0	0.0	0.0

After:

Parameters	MIN	MAX	AVG
Down Stream Line Rate	44.4 Mbps	47.9 Mbps	46.5 Mbps
Up Stream Line Rate	7.5 Mbps	7.7 Mbps	7.6 Mbps
Up Time	865.0 Sec	900.0 Sec	899.7 Sec
Retrains	0.0	1.0	0.0

Estimated line distance is 883.5

[#13]

How soon after the line reset were the second sets of statistics taken?

The reason I ask is that you will have gone on an open profile for the first 48 hours after the reset. At that point I think it would be difficult to assess the impact of the new socket.

[#14]

When I was first converted to FTTC my download speed was 17Mbps but after about 8 weeks it rose to 23Mbps. Got to be DLM that did that. I've been on 23Mbps for about 18 months, steady as a rock.

Probably not related but when they recently switched me to 55/10 and moved me to the Colindale BT centre it rose slightly to 24Mbps.

[#15]

Whereas when I came to PN (21 December) on FTTC, my download was around 27Mbps, this was showing as 30.8Mb (login req'd) and since the end of December it's slowly going down

Currently it's showing as 20.8Mb and I'm now getting below their lower estimate.

The link above now shows 20.8Mb and at the time of posting I'm getting around 17Mbps.

If PN read this, can I have my 10Mbps back now please!!