IDNetters Forums

Technical News & Discussion => IDNet Help => Topic started by: Danni on Feb 02, 2010, 21:27:06

Title: Pah
Post by: Danni on Feb 02, 2010, 21:27:06
So, apparently getting the noise margin reset was a bad thing. It keeps dropping out every 20 seconds or so, making the connection unusable.

No idea where the noise is coming from (new router, swapped filters, swapped cables, moved router away from computer) but right now I'd be happier if I had a lower sync and a slightly more stable connection.

Anything I can do? It's been doing this for hours according to Johan :(
Title: Re: Pah
Post by: Steve on Feb 02, 2010, 21:38:32
If you can't find the source of the noise your a bit stuck,surprised the exchange has not put your target margin back up.
Title: Re: Pah
Post by: Danni on Feb 02, 2010, 21:58:03
I'm surprised as well. I do want stability over speed, but at the same time wanted to see if it would work at the lower noise margin, as it did until the router died last year.

I wonder if the power problems damaged the line in some way?
Title: Re: Pah
Post by: Glenn on Feb 02, 2010, 22:00:22
What happens with the router plugged into the test socket behind the BT face plate?
Title: Re: Pah
Post by: Steve on Feb 02, 2010, 22:01:21
Or damaged something else, I have you tried the detuned AM radio trick to see if you can locate some possible interference
Title: Re: Pah
Post by: Danni on Feb 02, 2010, 22:16:08
Forgot the test socket... and on testing up to now, the noise margin jumped to 8.1 (on a 8128 sync) and it's stable again :)

Right, I'll leave it like that for now, and should I order a filtered faceplate? :)
Title: Re: Pah
Post by: Danni on Feb 02, 2010, 22:30:01
Thank you very much- still connected, nice maximum sync, decent noise margin... you guys rock :D

Now, filtered faceplate good? :P
Title: Re: Pah
Post by: Steve on Feb 02, 2010, 22:33:20
They're a great piece of kit no more fiddling with separate filters
Title: Re: Pah
Post by: Glenn on Feb 02, 2010, 22:33:29
It indicates that the noise is somewhere in you home, Danni. See if you can locate it, as Steve said.

Quote from: Steve on Feb 02, 2010, 22:01:21
Or damaged something else, I have you tried the detuned AM radio trick to see if you can locate some possible interference
Title: Re: Pah
Post by: 4Way on Feb 02, 2010, 22:39:24
I've recently found a noisy power supply to a Belkin USB hub using an AM radio. It was amazing how far around the house the interference could be heard. But as I narrowed down the areas I turned all the sockets off in the rooms until the interference  went then just went though the items in the room.   The PSU was less than 2m from the router so I was hoping for a big change in stats but no big change so far but it's early days.
Title: Re: Pah
Post by: Danni on Feb 02, 2010, 22:55:14
No idea where I'll get an AM radio from- I've only listened to internet radio for the past 7 years or so.

As there are no extensions or anything in the flat (new master socket was installed when I moved in), I'm not sure where the noise can be coming from other than the faceplate itself (and I wouldn't be surprised it was damaged when the router was). I figure there's nothing to lose by buying a filtered faceplate, and maybe some decent ADSL cable from ADSL Nation. The good news is that the router plugged into the filter with the phone straight into the test socket works fine now, so I can use it like that and maybe look more for sources of noise if the filtered faceplate doesn't work.

The only other new thing in that area is Johan's new monitor... and I don't think he'd be too happy with me unplugging that :P
Title: Re: Pah
Post by: 4Way on Feb 02, 2010, 23:01:54
Quote from: Danni on Feb 02, 2010, 22:55:14
No idea where I'll get an AM radio from- I've only listened to internet radio for the past 7 years or so.

As there are no extensions or anything in the flat (new master socket was installed when I moved in), I'm not sure where the noise can be coming from other than the faceplate itself (and I wouldn't be surprised it was damaged when the router was). I figure there's nothing to lose by buying a filtered faceplate, and maybe some decent ADSL cable from ADSL Nation. The good news is that the router plugged into the filter with the phone straight into the test socket works fine now, so I can use it like that and maybe look more for sources of noise if the filtered faceplate doesn't work.

The only other new thing in that area is Johan's new monitor... and I don't think he'd be too happy with me unplugging that :P

The noise can come from anything electrical but common items are central heating boilers and power supplies. If you can't borrow a portable radio, get a cheap one from asda or argos. It's worth doing even if it only eliminates that possiblity.Also try running routerstats (full or lite dependingon your router) to see it the inference happens at particular times which may help you trace it.
Title: Re: Pah
Post by: Danni on Feb 02, 2010, 23:14:48
The interference (whatever it was) happened consistently since the noise margin was reduced this morning, causing the router to resync every 20 seconds or so. The central heating was off then (it's back on now because it's cold still). There are power supply units in the area- for the router, and Johan's computer.

Maybe I don't get what the faceplate does- from what I'm reading, it picks up every bit of noise in the neighbourhood and makes sure you can't keep a stable connection, that's why going onto the test socket stablises it. Remember, there are no extensions connected at all, and the only difference between the completely unstable connection and the very stable one now is that the faceplate has been removed and I'm now connected to the test socket. The router hasn't been moved, the power supplies haven't been moved, the filter's the same, the phone is the same.

I will look into getting a radio. I'm housebound at the moment though so have to find somewhere to get one online.
Title: Re: Pah
Post by: PuncH on Feb 02, 2010, 23:45:21
it's more likely that your line just couldn't handle such a low noise margin, due to factors that are beyond your control.

my line has consistently run with a margin of 12db for years now until recently but that's another story, which is now (touch wood) sorted.
Title: Re: Pah
Post by: 4Way on Feb 03, 2010, 00:08:40
Quote from: Danni on Feb 02, 2010, 23:14:48
The interference (whatever it was) happened consistently since the noise margin was reduced this morning, causing the router to resync every 20 seconds or so. The central heating was off then (it's back on now because it's cold still). There are power supply units in the area- for the router, and Johan's computer.

Maybe I don't get what the faceplate does- from what I'm reading, it picks up every bit of noise in the neighbourhood and makes sure you can't keep a stable connection, that's why going onto the test socket stablises it. Remember, there are no extensions connected at all, and the only difference between the completely unstable connection and the very stable one now is that the faceplate has been removed and I'm now connected to the test socket. The router hasn't been moved, the power supplies haven't been moved, the filter's the same, the phone is the same.

I will look into getting a radio. I'm housebound at the moment though so have to find somewhere to get one online.

The filter is for telephones to work, your broadband doesn't need it. The adsl is a straight though connection, whilst the electronics,  in effect ,filter out the adsl so the voice side can work. It is possible that the filter has somehow got damaged and as you seem to have resolved the problem by using the test point, then replacing the filter is probably a good idea. If you only use the connection from broadband then just leave it in the testpoint.