Line speed even lower

These are the stats from my Zyxel P660HW-T1 from 2 different days :-
Date -------------------------------------- 14/04/11 ; 22/04/11
Time ----------------------------------------- 15:35 ; 09:42
Upstream noise margin --------------------------- 17 ; 19
Output power downstream ----------------------- 11 ; 12
Attenuation upstream --------------------------- 28 ; 28
Carrier load: number of bits per symbol(tone) --- 6-31 ; 6-31
Downstream noise margin ----------------------- 19 ; 23
Output power upstream ------------------------- 17 ; 17
Attenuation downstream ------------------------ 45 ; 46
Carrier load -------------------------------- 46-157 ; 46-155
Upstream speed Mbs ------------------------- 0.520 ; 0.513
Downstream speed Mbps --------------------- 1.934 ; 1.352

Is a higher noise margin better?

Is a higher attenuation better or worse?

I assume that the higher the output power the better, I hope that is correct.

Also, do any of these figures have any effect on download speed? I have used the BT online line checker from the local library to see if there is any noise on the line but it found no problem with noise, although I did hear noise on the line the last time I made a phone call.

Viv

A lower attenuation is better.

Regarding the noise margin; if one is syncing at the max, the higher the margin the better. If syncing at less than the max, a lower margin is better.

Your very high d/l noise margin indicates that you have a very poor line. Whether you will be able to do something about it is another matter. My parents have a similar margin to you, except they sync at their max speed - that is a much better line than they will ever need and I am jealous.

As regard higher power. The higher the better up to a point. If you have higer power then everybody will and interference between connection becomes significant past a certain point.

DrT

Edited by DrTeeth (Fri 22-Apr-11 10:53:25)

Thanks for that. I do not understand what you mean by 'syncing at the max'. How do I find out if I am, and is there anything I can do about it?

Viv

Increase in sync speed = decrease in noise margin, until a point where there is no more margin to increase the sync speed. If the maximum sync speed has been reached before the noise margin has been used up then the margin could be higher than 6dB.

You need to test your router plugged into the test socket found behind the master socket face plate.

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

Thanks, the router manual does not suggest that there is a way to adjust the sync speed. I will have to plug the router into the master socket, which is the very old style installed about 20 years ago, and check the router stats. Last time I did it all I did was run a speed check which showed an increase in speed which was nearly the same as I achieved last year. I did note that when I plugged the phones back in with the router still plugged in to the master socket there was little change in speed.

Viv

PS I did ask BT how much it would cost to replace the master socket with a modern one and they quoted £130, which did not seem value for money.

If you get a faster speed at the master socket it means that your internal wiring is below par. It also means that it should be easy to improve. Some Googling on the topic should bring up something that would help as will searching some of the relevant forums here.

Good luck in your quest and happy St George's day.

DrT

i had noise on my line i phoned BT,who did a couple of tests on line ,they agreed i needed an engineer,i had old gear fitted ,and BT replaced it and it cost me nothing,your paying for a servise so it should work ,go back to them,

Thanks, but if they send an engineer out and he/she decides that there is no problem with the line then I have to pay, which I believe may be in excess of £100. That is too much of a gamble for me.
As I have now changed ISP to BT and my line speed is usually in excess of 2.5Mbps I will settle for that. Infinity comes to my area in December so I may migrate to that next year.
Viv

The reason your speed has dropped is because if you notice your SNR has increased by a few DB which means that there is instabibility on the line. Who is your ISP?