ADSL Gurus

[Rasclart]

Right I know there are a few ADSL people on this forum.

Here is the situation, I am moving out to a house on 1st March.

The property according to checkers is about 3.9KM away from the exchange, and initial tests show it is POSSIBLE but not certain to get 512KB and no faster. In fact ADSL Max quoted as .25KB.

2 Doors down I know someone has ADSL, and the pub 200M away also has ADSL. The bloke on the phone seemed to be a bit relucatant but processed the order anyway. Activation is due 26th Feb

Are there any particular Routers, Filters anything really that will help with making the most of the a weak line.

I have a feeling when it is activated that I wont get Sync and a BT Engineer will have to come out, again what sort of things would they check or should they be checking.

Thanks Guys

 

[Lee]

It's ropey as f**k if you aren't close enough to the exchange. ADSL routers are designed to not work below a certain signal/noise level.

When I had mine increased to 8mb it became very unreliable as there wasn't enough noise on my line, anything below a certain amount the router has to renegotiate the link, so any speed increase was wiped out by the constant drop in the connection. In the end I removed a wire from the phone socket which helped matters no end. I get around 6mb now on a good day. I'm about 2 miles from the exchange.

The accepted levels are so low that it would need to be the speed of a 28.8 modem before BT or your ISP agree there's a problem.

I'm going to try the 16mb Sky service when I move in a few weeks. I reckon I'm closer to the Cannock exchange where I'm moving to, so in theory it should be okay!!

 

[Nigel]

Lee, I can remeber your thread about removing the wire. Can you remember which is was off the top of your head?

 

[sargey]

Try this guide....

http://www.readman.dsl.pipex.com/other/UKphonecatwiring.htm

Looks like the 3rd wire on terminal 3 + 4

Same guide on blogspot, with better photos
http://yarwell.blogspot.com/2005_08_01_yarwell_archive.html

 

[Lee]

It's in the second link sargey has posted Nige.

It helped mine no end, it actually stopped dropping the connection totally after I carried out the change. The phones in the house have been fine too.

 

[Rasclart]

That the ring wire or something like that?

 

[Lee]

That the ring wire or something like that?

Yeah, that's the one.

 

[sargey]

Try this link as well.

http://www.dslzoneuk.net/socket.php

 

[ViolentJ]

Personally I would always choose cable if it's available, that way you are getting what you pay for, none of this "up to" 8Mb.

We "upgraded" to 8Mb ADSL recently from 2Mb. My modem confirms it's an 8Mb connection but for some reason it still appears to be 2Mb i.e. my download speed is the same as it was on 2Mb and all the speed tests I have done say 1.5Mb - 2Mb. When I did one of those line checks that tells you what speed you 'might' be able to get it reported 6.5Mb.

 

[Rasclart]

Dont have the option of cable

Will give the ring wire a go and buy a couple of high quality ADSL Micro Filters and see how that goes first.

Apparently the Netgear DG834 has been seen holding a connection on a 0db and below SNR according to some links on SNR, allready have that Router ready. So shall see what happens next thurs when I move in!

 

[sargey]

How long ago did you upgrade?

They normally do test for a week or two, to see what your max. connection speed can be.

If its only been a week since you upgraded, don't worry as you might find you'll get a better speed soon.

Mine went from 2 meg to 4.5 meg over night!

 

[Lee]

Have a look here Chris: http://www.skyuser.co.uk/forum/tech...obtain-your-username-password-sky-router.html

There's some useful tools which will allow you to force your Netgear to not try and resync at certain noise levels.

It will allow you to pay with speed vs reliabilty pretty much. If I wasn't moving soon I'd probably lower the speed of my connection a little just to keep it stable, as I said it's a little ropey at times so the reconnects negate the speed increase!

 

[Rasclart]

Cool cheers Lee, had a look at that link on something unrelated the other day. I am not going to get a decent speed BUT I just want Broadband.

Allready spoke to the old man, going to leave an old computer at home in the Garage, as we have unlimited there at the moment and never drops below 220KB sec downloading from FTP on a 2MB line.

So hardcore downloading I can do there onto a Removable drive and collect on my way home from work. But would be a massive blow losing Xbox Live, and having to go Dial up!

 

[ViolentJ]

How long ago did you upgrade?

They normally do test for a week or two, to see what your max. connection speed can be.

If its only been a week since you upgraded, don't worry as you might find you'll get a better speed soon.

Mine went from 2 meg to 4.5 meg over night!

Friday last week, hopefully you're right!

 

[Lee]

Mine was dropping below 6db most the time before I removed the ring wire!

The noise margin is a figure that the router negotiates to give itself adequate leeway. For the Sky router the default it negotiates is 6.9db - think of it as 6.9db "in hand". At this figure the router performs well. Remember that the router will always try to sync at the highest possible speed at a noise margin of 6.9db or higher. It should resync automatically with ADSL2+ if the noise margin drops below this but sadly it doesn't (currently).

At a noise margin below about 6.2db the router starts to struggle so if the line noise increases after negotiation (i.e. the noise margin drops) then this can become a problem. The ideal noise margin is one where it never drops below ~6.5db at any time during the day.

You could set your noise margin at say 20db if you wanted but then you would be severely reducing the connection speed as higher noise margin = lower connection sync. However, a higher noise margin will tend to reduce transmission errors so really it is a case of experimenting if you want to squeeze every last kbps out of the line.

Generally speaking a noise margin of ~10.5db at the quietest time of day will tend to equate to ~7db at the noisiest.

 

[Darren S]

Same as you Rasclart - we don't get the option of cable.

I'm at the outer limits of the exchange's reach for ADSL. I currently get 1MB, but more usually 1.5MB. I'm trying the following after a very good recommendation. Maybe worth as shot for £12?

http://www.adslnation.co.uk/products/xte2005.php

D.

 

[Rasclart]

Yep been reading about them

First off I am going to try disconnecting the Ring Wire and have ordered a couple of ADSL filters from the same place. If not will go for a NTE5 socket from there!

 

[Mark5290]

Personally I would always choose cable if it's available, that way you are getting what you pay for, none of this "up to" 8Mb.

We "upgraded" to 8Mb ADSL recently from 2Mb. My modem confirms it's an 8Mb connection but for some reason it still appears to be 2Mb i.e. my download speed is the same as it was on 2Mb and all the speed tests I have done say 1.5Mb - 2Mb. When I did one of those line checks that tells you what speed you 'might' be able to get it reported 6.5Mb.

What modem/router are you using?, when i had my line upgraded i had to install the latest drivers for my modem(Thomson ST330) which changed the USB transfer mode from bulk to isochronous and tweaked a registry setting to allow for a higher download speed(so the Thomson website says).

The only problem is now that off peak i get a good connection speed of 5mb - 6mb, but during the weekend my connection speed is worse than a 1mb connection, so i shall be looking at changing my isp probably to an independent premium isp that does not traffic shape or throttle the bandwidth.

 

[GordonD]

The phone company requires ADSL modems (including the modem component in a combined modem-router) to operate correctly under specified signal to noise conditions. Most would do better than that minimum specification. Some are better than others. I'm not in your country, I don't know what approved products are available there, I don't know whether magazines in your country do the same tests, but magazines here test ADSL models to see what speed they can do at certain distances from the exchange and rate them accordingly. You should find someone's doing the same for similar products available in your country, and that if you buy the right router/modem you can get more speed.

 

[ViolentJ]

Personally I would always choose cable if it's available, that way you are getting what you pay for, none of this "up to" 8Mb.

We "upgraded" to 8Mb ADSL recently from 2Mb. My modem confirms it's an 8Mb connection but for some reason it still appears to be 2Mb i.e. my download speed is the same as it was on 2Mb and all the speed tests I have done say 1.5Mb - 2Mb. When I did one of those line checks that tells you what speed you 'might' be able to get it reported 6.5Mb.

What modem/router are you using?, when i had my line upgraded i had to install the latest drivers for my modem(Thomson ST330) which changed the USB transfer mode from bulk to isochronous and tweaked a registry setting to allow for a higher download speed(so the Thomson website says).

The only problem is now that off peak i get a good connection speed of 5mb - 6mb, but during the weekend my connection speed is worse than a 1mb connection, so i shall be looking at changing my isp probably to an independent premium isp that does not traffic shape or throttle the bandwidth.

I use ethernet so drivers aren't needed.

Modem: Linksys ADSL2MUE
Router: Linksys BEFSR81

I tried directly connecting to the modem just in case the router was causing an issue but no change.

I know it's not my pc at fault because my other halfs pc has the same results.

I use openSUSE 10.2, she uses Ubuntu 6.10.

Hopefully it's as been mentioned above about the ISP finding the best stable speed.

 

[Lagerlout]

I've just removed the bellwire -

Previous Line att - 45.0 db
SNR of 12db

now 43 and 10.4

My speeds have gone from 530 odd to 840!!! Go figure!!

 

[MOFO]

any links where i can test my bb speed please,

 

[MOFO]

so its worth doing?

 

[Lagerlout]

Well it's worked for me! I just note the speeds at which I dowload from a fast server - i..e Newshosting. The online bandwidth speed test have always seemed a bit hit and miss with me tbh

I don't fully understand ADSL and it's intricacies - My SNR and line attenuation don't seem to have altered much but I do know that the decibel is a logrithmic ratio of change rather than an actual unit of sound/noise so infact a 2db change could be quite significant. I need one of our resident ADSL gurus to confirm.

 

[Lagerlout]

Much better!! Extra 300KBps!!

 

[GordonD]

attenuation : smaller number is better
signal to noise ratio : bigger number is better

It is better that your attenuation has gone down. That improves the speed you can get out of a line. But its bad news that your signal to noise ratio has fallen. That may though simply be the result of the line speed going up.

Here's the spec:

Downstream Attenuation
0-42 dB - 2Mbps [SIZE=-2](strictly adhered to wef Aug 2005)[/SIZE]
43-60 dB - 1Mbps
> 60 dB - 512kbps
If you already have adsl enabled you may be able to add an extra couple of dB on those figures e.g. 44 dB would be the limit for a 2Mb line. However, since Aug 2005 BT have adhered to the rules more due to the large number of recently failed 2Mb upgrades that have had to be regraded down to 1Mb.
There is a supposed soft-cap of about 70dB, but BTw wll try connect anythng up to 75dB attenuaton
Downstream SNR Margin
Should be at least 10 dB to get adsl - ideally above 12dB to get traditional fixed adsl.
Anything less than this will see frequent disconnections and other problems.
Maxdsl works slightly differently and your router will try to sync at the highest speed it can whilst maintaining a safe SNR Margin. The default is 6dB but more info on my max dsl page.
As previously stated these figures should be used as a guideline as it is possible to have a very good SNR Margin but poor attenuation figure and vice versa.

 

[GordonD]

Never bothered looking at my modem/router's ADSL attenuation and SNR before. Turns out its attenuation = 57.1 dB, and SNR = 17.9 dB. Wow, I knew I was a long way from the exchange, but I didn't realise I was that far. And I'm successfuly running 1536 Kb/s downstream.

 

[MOFO]

mine goes through a splitter box, can i still do this?

 

[MOFO]

its a bt adsl mf50, i opened it up and looks all funny lol. no wires just loads of red and black things.

 

[Lagerlout]

LOL

Dude. Tell me you haven't dismantled your modem/router?

 

[MOFO]

no i have a spare lol,y cant i do it, i only get speeds of 100kbs ish,

 

[Lagerlout]

attenuation : smaller number is better
signal to noise ratio : bigger number is better

It is better that your attenuation has gone down. That improves the speed you can get out of a line. But its bad news that your signal to noise ratio has fallen. That may though simply be the result of the line speed going up.

Here's the spec:

Downstream Attenuation
0-42 dB - 2Mbps [SIZE=-2](strictly adhered to wef Aug 2005)[/SIZE]
43-60 dB - 1Mbps
> 60 dB - 512kbps
If you already have adsl enabled you may be able to add an extra couple of dB on those figures e.g. 44 dB would be the limit for a 2Mb line. However, since Aug 2005 BT have adhered to the rules more due to the large number of recently failed 2Mb upgrades that have had to be regraded down to 1Mb.
There is a supposed soft-cap of about 70dB, but BTw wll try connect anythng up to 75dB attenuaton
Downstream SNR Margin
Should be at least 10 dB to get adsl - ideally above 12dB to get traditional fixed adsl.
Anything less than this will see frequent disconnections and other problems.
Maxdsl works slightly differently and your router will try to sync at the highest speed it can whilst maintaining a safe SNR Margin. The default is 6dB but more info on my max dsl page.
As previously stated these figures should be used as a guideline as it is possible to have a very good SNR Margin but poor attenuation figure and vice versa.

Cheers pal.

I'm not surprised mines not brilliant - There are like 8 phone sockets in my house (put in by the previous owner and they are all just extended in series. Get lots of interference when using the phone too.

Chuffed to bits about gaining all that extra speed just by pulling a couple of wires. Just have to see how reliable it is, although I'm on ADSL max so it should sort itself out to a stable level.

 

[MOFO]

liango, can i not do it for higher speeds, also any links to where i can test my maximum spped fir the line, im on 8meg bb but ony getting 100kbs ish.

 

[Lagerlout]

no i have a spare lol,y cant i do it, i only get speeds of 100kbs ish,

You need to disconnecting wires 3 and 4 in your master phone socket not your f**king router!!!!!!1 LOL

Have you even read this thread?

:banghead:

 

[MOFO]

ok but the master socket is just for the phone lol, not lijke the diagrams in the links above.

 

[Lagerlout]

Christ on a bike.

I have neither the time or the patience to help someone who cannot be bothered to read!!

 

[MOFO]

right check this out, just took mine to bits and have nw read the thread so sorry, wires 3,4 and 6 are not connected???????? why?????

 

[MOFO]

any1?

 

[Lagerlout]

You sure you're looking at the master socket? The one in you're house where the BT cable coming into your house goes into?

 

[MOFO]

yes, its in my living room and was told its the master socket