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[chris87]

hey guys i tested my master socket to see if thier is any improvements and wow my downstream SNR is now 30db but line attenuation is 60 what speeds can i now roughly get? any suggestions 

[kitz]

We'd need to see your full stats to make a more accurate judgement (it depends what speed youre currently syncing at so we can judge better the "spare" noise margin)

Your attenuation shouldnt change whatever speed youre on - but SNR Margin is affected by your sync speed.
The higher your sync speed, then it will lower your SNR Margin.

60dB indicates a very long line - which are more susceptible to noise fluctuations so could be anything from 1-2 Mb.
If your line is one of those that fluctuates a lot - then you may be better on a fixed rate service rather than max.

[chris87]

that was on a fixed 500k line it used to be 15db SNR downstream which is not very good until i used the master socket which went straight up to 30DB SNR downstream

[kitz]

http://www.kitz.co.uk/adsl/max_speed_calc.htm

If all goes well then you should get around 2Mb throughput on Max.
The warning though is always there - it depends how stable your line is.
If it starts playing up a bit then the BT dlm system will increase your target snr which would reduce the max speed you can connect at.

You will also be affected by the IP profile

[mr_chris]

Longer lines tend to be more difficult to predict - it all depends on how your line handles higher frequencies. Perhaps you'll only get 1Mb, perhaps 2Mb, who knows.

But with 30dB SNR on 512k, provided everything's being reported correctly, it's pretty safe to say that Max is likely to produce a significant improvement over your existing connection

[chris87]

at master test socket

Connection Speed 608 kbps 288 kbps

 Line Attenuation 60.0 db (downstream)              31.5 db (upstream)


      Noise Margin 29.4 db (downstream)                    24.0 db(upstream)

any rough estimation of what broadband speed i can get with them line stats? i have a netgear router DG384GT

(my SNR is also very very stable at my test socket) so whether that also helps to get higher speeds





at extension socket

Connection Speed 608 kbps 288 kbps

Line Attenuation 61.5db          db 31.5 db


Noise Margin 19.5 db 23.0 db

[mr_chris]

Obviously you see the SNR reduces significantly when you use your extension socket. You've got a very high attenuation but also an unbelievably high SNR for that attenuation at that speed!

I reckon on 1.5 to 2Mb, perhaps

[chris87]

thanks

[guest]

2Mbps down looks possible. Your upstream will probably handle 1Mbps, but you won't get that from anyone other than UK Online/Sky or Be.

Why is your downstream showing 608kbps?

[kitz]

With the high SNR Margins - it looks like the ISP has perhaps "fix rated" the line?
Not sure what profiles Karoo have. (KCC)

[guest]

Looks rather odd to me as upstream is 288kbps - just like a BT 512kbps line would be. I wonder what the extra 32kbps downstream is being used for as the line is a fixed 500kbps line according to chris87

[mr_chris]

Yeah, Kingston (Hull) of course have their own phone exchanges, as you probably know.

They have always stuck an extra 32kbps on the sync speed, perhaps to allow users to experience actual payload throughput of 500kbps on speed testers. Relatively little skin off Karoo's nose, and it makes them look slightly faster than the BTw equivalent connection? Just a theory I've had for a while!

[guest]

Ahh of course the ATM overheads. Been living with them (apart from Be) for so long I tend to forget/filter them out

[chris87]

hmm i dont really know to be honest i wish i was on BT though but i can only use KC karoo as my ISP

[chris87]

i have also got a few more questions

my netgear router drops my SNR i usually have around 29.7db all day and it doesnt move really at all but then all of a sudden it can drop to like 27db then i reset my router and it goes back up to 29.7 to 29.9db SNR downstream its not much of a SNR drop but is this normal for a router to do that?

also at what SNR margin would my connection drop i heard its 8db and below am i right?