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[waltergmw]

Hi Limbo,

I've not seen that VDSL2 emulate screen before either, so it is very valuable indeed. On NO account loose It !

VDSL is still a new technolog for me but I would certainly disconnect the bell wire just in case, but I'd wait for a time preferably around 14:00 to disconnect the modem.
When you do I suggest you turn the mains off at the power supply. Some modems have some last gasp logic so it's good practice, even though I don't know if that is implemented in your new modem.

It's a good idea to optimise your line as soon as you can and before the training period expires so you get the best possible stable connection.

Currently your bRAS is at 26726 k which looks as if it might have improved a bit since the JDSU reading, assuming that the same 82.5 % of sync rate applies to the VDSL connection.

EDIT I've just remembered from ADSL days that the JDSU instrument does not synchronise as fast as say a 2700 HGV so it's also possible that the same thing happens with VDSL.

@ RP with your experience, can you add anything to this piece please ?

Sorry this is all a bit empirical !

Kind regards,
Walter

[burakkucat]

@Walter -- Unfortunately Mr Pag left us yesterday and asked for his account to be deleted. If you send a PM to Eric, I'm sure he will fill in the details for you.

b*cat is rather unhappy with what has happened and also the way it happened. RP was a friend and valuable source of technical information for us all.

[Bald_Eagle1]

Unfortunately Mr Pag left us yesterday and asked for his account to be deleted.

b*cat is rather unhappy with what has happened and also the way it happened. RP was a friend and valuable source of technical information for us all.

Hi Folks,

I have not been a member of this forum for long, but I too am sad that RP has departed (for whatever the reason).

His general technical advice & feedback from "Johnny on the spot" has been partly my inspiration for keeping going with my own quest and I'm sure his departure will be a sad loss to the Kitz forum as a whole.

Paul.

[waltergmw]

Hear hear !

Kind regards to RP and many thanks for all the hours he has devoted to us.

Walter

[limbo]

Hear hear !

Kind regards to RP and many thanks for all the hours he has devoted to us.

Walter

While I didn't have any direct contact with RP, reading through threads, it was clear that he was a valuable contributor to these forums, and we will all miss his contributions 

[limbo]

Well Thomas, you're not stuck in limbo any more then 

Absolutely not!

The engineer seemed to be quite helpul & obliging & hopefully your various line issues have now been permanently fixed.
I'm not sure about the bell wire though. Someone else may advise you to remove that???

What surprises me and I think surprised him, is that we never heard any crackling on the line (symptomatic of an HR fault- the broken wire in the cab).

It should take around 10 days or so for your speeds to stabilise.
Are you happy with the current speeds? They are a lot higher that your "meaningless" estimated speeds.

I guess for a line of my length it's probably as good as it's going to get- I count myself lucky that we are able to get FTTC. I do hope that it keeps up at these speeds, though.

I'm really glad that you managed to take a photo of the JDSU showing the estimated line length. None of my visiting engineers have shown that display to me. More than one visiting engineer told me that the JDSU could not display that sort of detail when I asked them for it

I will be using your photo as evidence (if you have no objection) when the next engineer vists me, hopefully during this week.

I believe that line length is estimated via the JDSU mainly based upon on the attenuation figure, but more knowledgeable people than I aren't really quite sure for VDSL2 purposes. It may well take other factors such as SNR levels into account.

By all means show them the picture- perhaps you'll teach the engineers something!

Due to your actual or estimated distance from the cabinet, it is very unlikely that 40 Mb would be delivered to your home.
Others with guesstimated line lengths of around 650m & a JDSU attenuation value of around 19dB or so have been achieving download speeds of around 37Mb, more or less the full whack available, less a bit for overheads.

The IP Profile & download speeds as shown in the BT speed tester & the engineer's JDSU apparently always appears a bit more pessimistic than actual download speeds as shown by other speed testers such as speedtest.net.

If the line length is 900m or thereabouts, I guess these kinds of speeds make sense.

All I would suggest is that you regularly monitor your download speeds as reported by speedtest.net for consistency, along with regular BT speed test results (save the screenshots).
If nothing else, you will have a good record of your connection's capabilities if your speeds should start to plummet outside the 10 day training period. Your speeds may well even increase over the next few days.

I hope you're right- I've only had one disconnection so far- that was at 2.30 in the morning. Not entirely sure why it happened then (we were all fast asleep).

EDIT: Just for curiosity, which version of the modem has BT supplied for you?
It should be displayed on a sticker underneath the modem, the firmware version ending in SP06 or SP10, & the hardware version may have a 2V or 2B sticker, also underneath.

Also please see the PM that I sent to you

The modem is 2B HW, with SP10 SW.

I'll reply to your PM after this 

Thomas

[limbo]

Hi Limbo,

I've not seen that VDSL2 emulate screen before either, so it is very valuable indeed. On NO account loose It !

VDSL is still a new technolog for me but I would certainly disconnect the bell wire just in case, but I'd wait for a time preferably around 14:00 to disconnect the modem.
When you do I suggest you turn the mains off at the power supply. Some modems have some last gasp logic so it's good practice, even though I don't know if that is implemented in your new modem.

It's a good idea to optimise your line as soon as you can and before the training period expires so you get the best possible stable connection.

Currently your bRAS is at 26726 k which looks as if it might have improved a bit since the JDSU reading, assuming that the same 82.5 % of sync rate applies to the VDSL connection.

EDIT I've just remembered from ADSL days that the JDSU instrument does not synchronise as fast as say a 2700 HGV so it's also possible that the same thing happens with VDSL.

@ RP with your experience, can you add anything to this piece please ?

Sorry this is all a bit empirical !

Kind regards,
Walter

Hi Walter,

I won't lose that picture!

I haven't actually put the Faceplate back on yet, since I'm still messing about with the extension wiring in the loft (separate thread going to appear soon regarding the best way to do it!).

I've attached a BT speedtest screenshot from last night, and this morning, in case anyone is interested.

Oh and PN have definitely set the line speed at 37Mb- it says so on my account there!

Edit: So it seems that the one disconnection has reduced my IP Profile by a tiny bit

[attachment deleted by admin]

[burakkucat]

I'm really glad that you managed to take a photo of the JDSU showing the estimated line length. None of my visiting engineers have shown that display to me. More than one visiting engineer told me that the JDSU could not display that sort of detail when I asked them for it

I will be using your photo as evidence (if you have no objection) when the next engineer vists me, hopefully during this week.

I believe that line length is estimated via the JDSU mainly based upon on the attenuation figure, but more knowledgeable people than I aren't really quite sure for VDSL2 purposes. It may well take other factors such as SNR levels into account.

Mr Eagle, I believe the JDSU measures the line length by sending out a small pulse (a ping) and timing how long it takes for the response (a pong) to appear. Electricity flows at a constant speed . . . so the distance is just (0.5 * C / (pong - ping)).

[renluop]

Will the Chinese have pangs, when they realise you're playing pomg-ping? 

[burakkucat]

Will the Chinese have pangs, when they realise you're playing pong-ping? 

Most definitely!

[waltergmw]

@ BKK,

Just to clarify (I hope), it must be an intelligent Ping to which the FTTC DSLAM recognises and thinks this pongs !

This is as opposed to the physical line tests the JDSU performs which can cover the entire line length back to the exchange.

Kind regards,
Walter

[burakkucat]

it must be an intelligent Ping to which the FTTC DSLAM recognises

Yes, that is my understanding of how the JDSU operates when making that measurement.