Noise Bursts

[Sebby]

I've been having this issue for months. Sometimes it's intermittent, sometimes it lasts for weeks then disappears for a while. I cannot get to the bottom of it.

I have an ADSL Nation XTE-2005 and a SpeedTouch 585v6. Obviously my internal wiring cannot be to blame. I have tried another router and the test socket to rule out the filter and router.

I always sync'd at approximately 4.5Mb @ 9dB (manually set by BT for less errors on my line). I never used to have any problems, but then a couple of months back my router sync'd significantly lower (about 2.8-3Mb @ 9dB) suggesting that there was a lot more noise around. Attenuation had remained unchanged, so someone on TB suggested that the likelihood was that the source of the noise was close to home.

During one of these periods where there was a lot of noise around (and therefore the router had lost sync and resync'd at a low rate @ 9dB), I went around the house switching everything off (boiler, fridge, freezer, etc) to see if the noise margin improved, but nothing made a difference. To this day I can't find anything at home that's causing the noise.

It is getting so frustrating - sometimes (like this morning) these bursts of noise cause several resyncs, and once again my margin has gone up to 15dB. I know a guy at BT who'll reset it for me, but it's not an answer to the problem.

I want to find the cause of this issue! Can anyone give me any advice, or have I exhausted all options already?

[Rik]

Have you done a walkabout with a de-tuned AM radio, Sebby. That will usually pick up any local noise generation. Otherwise, I suspect that, like me, the noise is external and it will be exceedingly hard to track. Mine seems to have periodic bursts in the 1am-3am period, and I half wonder whether it's anything to do with engineering works on the railway - about a mile away. It's noticeable that Sunday is the worst day.

The one thing I've found which really helps is the 2700 router, which is less inclined to let go of the line and, when it does, it re-syncs at a higher speed than anything I've had before.

Given everything else you've tried, the only other thing I can suggest is getting a BT engineer out via IDNet, but there's the risk of a hefty charge that way. I'm just wondering if you could get switched to a different pair...

[Sebby]

Thanks, Rik. I haven't tried a de-tuned AM radio - can you give me some more information about this?

I suspect that you're right in that the noise is external. I can tell it's going to be one of those things that I won't get to the bottom of.

I started watching a 2700HG on eBay this morning as it so happens, and I've just won it at £9.04 delivered (it's a refurb from DigiDave), so I'll give that a go. I'm not sure it'll work, as what seems to happen on the SpeedTouch is that there is a huge influx of noise that causes errored seconds and a loss of signal.

I'm very sceptical about getting BT involved. I'd love to get swapped to another pair, but I doubt they'd even agree to it to be honest. They'd take one look, see that I've got a fairly decent sync, and there'd be no fault found. I know there's something wrong, but it wouldn't look that way to BT. 

[Rik]

I agree with you, Sebby, I think it's going to be very hard to get BT to accept a fault - but ti would be worth talking to IDNet as they may be able to build a picture of your line which would reveal the issue.

As to the radio, any battery-powered AM radio will be fine, tune is away from a station, so you just have white noise, then run it along the route of your phone cable and around electrical appliances, including fixed items like your CH boiler, and see if it starts to buzz. If it does, you've got noise in the ADSL operating range.

[Sebby]

I'll try and get hold of a radio, Rik (I can't believe we haven't got one here!).

I'm hoping that the 2Wire will help, though I'm remaining sceptical as the 585v6 is supposed to be a pretty decent router anyway.

[Rik]

I'll try and get hold of a radio, Rik (I can't believe we haven't got one here!).

I had the same problem after moving to DAB.

I'm hoping that the 2Wire will help, though I'm remaining sceptical as the 585v6 is supposed to be a pretty decent router anyway.

It may not, tbh, but it's one of the few things you can try in your situation.

[merlin]

i have been wondering if in this type of situation, whether some sort of mains filtering would help, i do,nt mean the lightning strike type filtering.

something like the type you would use to remove noise as seen on an oscilloscope ,generally known as grass, where you are supplying power to sensitive test equipment for instance.

[Rik]

It might do, but I don't know for sure. I run all my equipment through conditioning UPS to mimimise problems.

[Sebby]

All my equipment is connection the Belkin surge protectors, but there's no mains conditioning.