Today's a good day to remind you

Rik · Jul 17, 2009, 11:45:42

... that thunderstorms and ADSL don't mix very well. Two things can happen. First, the electrical noise generated by the storm can force your line to re-sync at a lower speed, sometimes giving you a profile problem for a few days (in the worst case, it might also trigger an increase in target noise margin, which is much harder to resolve). Second, if there's a lightning strike near you or the exchange, it creates a situation where earth (ground) potential can differ, and that will cause excessive current to travel along the phone line. That current can destroy your router and, in the worst case scenario, your computer.

My advice, during storms, is to power down your router at the mains, then unplug it from the phone socket and wait for the storm to pass.

I always monitor noise margin during a storm, using RouterStats, and keep an eye on this site, which plots the lightning activity:

http://www.ukspeedtraps.co.uk/weather/light0900.htm

Simon · Jul 17, 2009, 12:23:24

Thanks for the timely reminder, Rik. That's exactly what I did yesterday evening, which is why I wasn't here till quite late.

Sebby · Jul 17, 2009, 13:16:33

Thanks, Rik. Shouldn't it be thunderstorm's and BT's implementation of ADSL that don't work very well together?

Rik · Jul 17, 2009, 13:17:14

This is also true.

john · Jul 17, 2009, 13:25:15

Good advice Rik, and to make doubly sure I always climb up the the nearby telegraph pole and snip the cable that runs to my house (you've got to be careful to choose the correct one and not accidentally cut one's neighbours like I once did

). I then use a ladder to get to where it connects to my house and cut it there too. With the cable completely removed I think it's very unlikely that the lightning will jump the 50' gap between my house and the pole.

When the storm is over I find that there's just enough slack in the cable to lash it back together again using a tried and tested reef knot which doesn't appear to affect the connection too much

coreservers · Jul 17, 2009, 13:51:09

us at sky connect pray for a thunderstorm to blow up the router. for that moment you actually get somewhere near normal speed.

JohnH · Jul 17, 2009, 14:15:15

I think the storm last night must have blown up BT's DLM at my exchange:

Test1 comprises of Best Effort Test: -provides background information.
Your DSL connection rate: 4512 kbps(DOWN-STREAM), 448 kbps(UP-STREAM)
IP profile for your line is - 4500 kbps
Actual IP throughput achieved during the test was - 3728 kbps

I should have an IP profile of 3500 kbps for a connection rate of 4512 kbps

It's been like that since the power came back at midnight. Maybe another storm and power cut might get the profile up to 5500.

David · Jul 17, 2009, 14:15:55

I too unplug and also unplug the sky if its really bad I will remove the tv Ariel from the wall socket.....

I will have to learn Johns method its rubbish but sounds great fun

David · Jul 17, 2009, 14:18:08

QuoteI always climb up the the nearby telegraph pole and snip the cable that runs to my house

Shocking John......steps need to be taken

Rik · Jul 17, 2009, 14:47:38

Quote from: john on Jul 17, 2009, 13:25:15
When the storm is over I find that there's just enough slack in the cable to lash it back together again using a tried and tested reef knot which doesn't appear to affect the connection too much

David · Jul 17, 2009, 14:52:22

Not off topic (makes a change) when I had a problem here with my line a very common thing was found to be causing speed issues which I havnt seen mentioned and that was the phone lines had actually rusted where they connect on the pole so just thought it may interest some !

Ok its not big news but hey ....it is raining again

Rik · Jul 17, 2009, 14:52:48

Oh no it's not.

David · Jul 17, 2009, 14:57:55

Oh yes it is ..........its pouring here my poles getting soaked....

Nice girl

Rik · Jul 17, 2009, 14:59:08

Slippery, though.

David · Jul 17, 2009, 15:04:46

Dont take me there Rik

Rik · Jul 17, 2009, 15:06:09

I'm at the 'elm, don't worry.

David · Jul 17, 2009, 15:45:35

Root and branch eh !

Rik · Jul 17, 2009, 15:48:34

Let's leaf it there.

David · Jul 17, 2009, 15:50:34

Atreed

Rik · Jul 17, 2009, 15:55:09

You've just twigged, haven't you.

David · Jul 17, 2009, 15:57:59

I had better log this thread

And its stopped raining so my thingies wont rust after all

Rik · Jul 17, 2009, 16:01:16

That's good. Rusty thingies can be painful.

Sebby · Jul 17, 2009, 16:18:23

Quote from: lodge on Jul 17, 2009, 14:15:15
I think the storm last night must have blown up BT's DLM at my exchange:

Test1 comprises of Best Effort Test: -provides background information.
Your DSL connection rate: 4512 kbps(DOWN-STREAM), 448 kbps(UP-STREAM)
IP profile for your line is - 4500 kbps
Actual IP throughput achieved during the test was - 3728 kbps

I should have an IP profile of 3500 kbps for a connection rate of 4512 kbps

Stuck high profiles do happen, but it's rare.

Rik · Jul 17, 2009, 16:19:00

I did have one for a while, but BT noticed.

vitriol · Jul 17, 2009, 19:41:18

Cheers Rik,

It's been raining heavily here in Durham all day, just logged on to find my sync has dropped from 8128 to 7648 ish, so thanks for the reminder. How long will it take to recover do you think?

john · Jul 17, 2009, 20:00:37

Quote from: Rik on Jul 17, 2009, 15:06:09
I'm at the 'elm, don't worry.

David's still probably 'pine'ing for her

David · Jul 17, 2009, 20:21:25

Rik · Jul 18, 2009, 11:34:09

Sync? As soon as the storm passes. Profile, about 5 days.

Lance · Jul 18, 2009, 23:21:23

Might be worth noting though that to recover sync, you have to initiate it, either from within the router software or by pulling the plug on the router.

vitriol · Jul 19, 2009, 00:11:55

I rebooted router about an hour after my original post and sync is back to normal.

Sebby · Jul 19, 2009, 14:58:09

Glad to hear it.

DarkStar · Jul 30, 2009, 15:48:55

Anybody else find that this site is not displaying any lightning info/maps these last few days. I have the site bookmarked so that I can quickly see if there is any activity in my area.

http://www.ukspeedtraps.co.uk/weather/light0900.htm

I like to know if what I thought was a rumble of thunder was in fact an empty container lorry going down the hill outside or not

Rik · Jul 30, 2009, 15:51:19

It seems to be down on the triangulated stuff, Ian. ISTR him posting something about that network shutting down.

DarkStar · Jul 30, 2009, 15:59:34

That was quick Rik.
Yes, I seem to remember seeing something a while ago but as usual these days I didn't pay much attention. Hope it's going to come back up, it's one of the more useful bookmarked sites I have.

Rik · Jul 30, 2009, 16:02:07

I agree, Ian, I always run it and Routerstats when there's thunder about. Between watching the NM and the map, I know when it's time to power off and go read a book.

Rik · Jul 30, 2009, 16:03:42

My alternative site:

http://www.isleofwightweather.co.uk/live_storm_data.htm

is suffering the same problem, btw. For that matter, all my radio-controlled clocks lost signal at lunchtime - so I used that as a warning.

DarkStar · Jul 30, 2009, 16:26:02

At least that Isle of Wight site has some info on it.
I have sent UKSpeedTraps an e-mail, will post when/if I get a reply.

Rik · Jul 30, 2009, 16:26:34

Thanks.

rireed3 · Jul 30, 2009, 16:45:10

On the subject of thunderstorms --

If someone were waiting out the 14 days for reduced target margin (not me), what would be the best policy if the storms started coming through? You don't want to re-sync even on purpose, but maybe once or twice a day at the same rate isn't too bad?

Richard

Rik · Jul 30, 2009, 16:48:37

In your case, Richard, I'm afraid you'd be stuffed. A single re-sync will re-start the clock, and if there are any errors on the line, likely in a storm, BT will see that as unstable so won't lower the margin. You may just as well pull the plug and resign yourself to another two weeks. Crazy, but BT make no allowances for anything.

DarkStar · Jul 30, 2009, 18:22:47

Have received a reply from SpeedTraps. Steve says it is working fine his end and that it may be because I have not got Java enabled, which I hadn't. However I never have Java enabled. If I enable Java I now see the same 'map' that you see on the Isle of Wight site but still nothing for the 'Triangulated Data' maps. Have tried playing with my Flash settings and no joy there, so will just have to hope the Triangulated Data comes back on stream sometime.

Rik · Jul 30, 2009, 18:24:27

It's still down here, Ian, with Java up and running. Hopefully, someone will put 50p in the meter soon.

Sebby · Jul 30, 2009, 19:31:04

No problems here, as far as I can see...

Rik · Jul 30, 2009, 19:39:04

You're getting the three triangulated images, Seb?

Sebby · Jul 30, 2009, 19:40:48

Um, maybe not actually.

[attachment deleted by admin]

Rik · Jul 30, 2009, 19:41:28

Cheat, it's the next three we need.

Sebby · Jul 30, 2009, 19:42:07

Oh, sorry, I'd never noticed there was anything below that. Nope, not working for me in that case.

Rik · Jul 30, 2009, 19:45:36

They're the useful ones, Seb, as they pinpoint the real location, while the top map can be wildly out.

Sebby · Jul 30, 2009, 21:30:39

Ah. That's something I've learnt today!