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Standard User Chrysalis
(eat-sleep-adslguide) Thu 27-May-10 19:51:29
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flourescent lights, noise interference part 2


[link to this post]
 
here is a pic of my noise margin graph with SRA disabled. Obviously the line would be more likely to drop, so I deliberatly had coding gain on 0, surprisingly is still holding tho.

target snrm 7, I know is rarely near 7db smile

Noise Margin - No SRA

2nd graph it appears the 2nd interference isnt present so can see the 1st interference constantly coming and going.

Noise Margin 2nd day - No SRA

Edited by Chrysalis (Thu 27-May-10 19:54:25)

Standard User tommy45
(experienced) Thu 27-May-10 21:30:19
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Re: flourescent lights, noise interference part 2


[re: Chrysalis] [link to this post]
 
Just thought i would link to the first part:
Link to Part 1


Well not allot in the way of progress,But it's looking like i may have to get a billion router, so i can change the snrm, to suite conditions, ie, raise it during periods the shop lights are able to affect my connection and lower it when it has ceased,as the dslam at my exchange seems to stick to g.dmt mode, so i'm unable to re-sync using other modes, unless my isp manually changes mode, and i doubt that they would want to do that every day, , But switch of modes the other day has changed things a little in my favor, i think this because it got a slightly higher sync than it did previously,and the level of packet loss & crc errors were lower, so the throughput was more constant too, but not as good as when the lights in that shop are switched off,

Standard User Chrysalis
(eat-sleep-adslguide) Fri 28-May-10 09:12:08
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Re: flourescent lights, noise interference part 2


[re: tommy45] [link to this post]
 
the situation reversed without SRA.

the daytime on both days for packetloss is cleaner but not 100% clean.

however the large loss of snr to the night causes significant packetloss at night. This is a problem I had for many years before I started using SRA having to get the line stable for day and night without syncing really low. The sync is 5.3mbit.

Overall tho it worked better than expected on that little experiment.

with the billions you will have 2 methods of changing sync speed, both the snrm overide and coding gain settings, coding gain can be adjusted in the gui so is easier.


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Standard User tommy45
(experienced) Fri 28-May-10 13:39:37
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Re: flourescent lights, noise interference part 2


[re: Chrysalis] [link to this post]
 
Coding gain, how does this work, similar to the way snr does?
Well for some reason it appears that i has dropout earlier, strange, routerstats logs show it,so does the router's log, and it's shown on the tbbqm too, but the sync,snr graphs do not show it,odd to say the least, but something has changed, as the throughput seems to have reverted back to how it was before, not good,

From router stats log, it would appear that my ip address became inactive ? as for whatever the reason it changed from the usual static ip, to the 0.0.0.0 and back to my same ip some 5 mins later ????

Edited by tommy45 (Fri 28-May-10 16:39:06)

Standard User Chrysalis
(eat-sleep-adslguide) Fri 28-May-10 13:44:36
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Re: flourescent lights, noise interference part 2


[re: tommy45] [link to this post]
 
not that sure how it works.

I believe it is more agressive on the signal utilisation similiar to how interleaving increases sync.

the simple bit is low coding gain = low sync speed and high coding gain = high sync speed, it doesnt affect the noise margin. However higher coding gain will also increase chance of crc errors and the sync dropping.
Standard User tommy45
(experienced) Sat 29-May-10 19:57:54
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Re: flourescent lights, noise interference part 2


[re: Chrysalis] [link to this post]
 
I have been checking over things again today looking for any clues of any other reasons for this E M I Possibly a new discovery
I think that even the shop's alarm is showing up on the ping plotter charts, but oddly enough i don't seem to be able to see it after closing of the shop tonight as i was walking past the shop on my way home, i noticed that the owner was in the shop but had all but one of the shops lights off, the light that was on was the office light, got home the majority of error's had stopped and so had virtually all the pkt loss,12HR time span graph and as an example of how many errors this degree of packet loss generate in 1 hr

From 15:02 to 16:02 there was 124542 corrected crc errors & 3599 uncorrected erroneous seconds but as i write this the in the past hour 18:45 till 19:45

249 corrected crc errors 175 uncorrected erroneous seconds & 2 serious erroneous seconds , So when this shop aint got its lights on my connection is not producing more than it should do given that it is on fastpath

Standard User Chrysalis
(eat-sleep-adslguide) Mon 31-May-10 15:38:29
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Re: flourescent lights, noise interference part 2


[re: tommy45] [link to this post]
 
if you do get a billion 7402 and want proper snrm and speed graphs I can graph it remotely for you on a cacti server no problem, just pm me if you want to do this after you get the router. The error count stick to using tbbq for that. Routerstats wont work on the router.
Standard User tommy45
(experienced) Mon 31-May-10 15:51:33
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Re: flourescent lights, noise interference part 2


[re: Chrysalis] [link to this post]
 
Does the router (billion) not have a built in counter for viewing the crc's erroneous secs ect? the ping plotter and tbbqm only really show packet loss, and by a percentage, where as being able to count the errors that build over a say 15mins time frame gives a reasonable idea how bad or good things are Well no packet loss or large amount of errors yesterday or today ,apart from the strange happenings earlier today all has been ok, thank's for the offer, i will probably take you up on it once i get the router ,

Edited by tommy45 (Mon 31-May-10 16:18:44)

Standard User Chrysalis
(eat-sleep-adslguide) Tue 01-Jun-10 14:55:51
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Re: flourescent lights, noise interference part 2


[re: tommy45] [link to this post]
 
yes you can check it manually, but only via telnet. The gui counter seems to check the wrong variable.
Standard User tommy45
(experienced) Tue 01-Jun-10 20:41:48
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Re: flourescent lights, noise interference part 2


[re: Chrysalis] [link to this post]
 
Well after a great 2 days of a EMI free Internet connection Sat night through to this morning when Those lights got switched on,as a test i made sure that i was downloading a test file,which was maxing out my connection, then suddenly the data stream being received stopped completely due to the switch on of the lights. it after a few mins started tricking though again, at a few hundred kbps ,
Results of errors recorded yesterday after almost 9hours and plenty of data uploaded and downloaded totaling nearly 20gb,
3760184----138922------101717--ppp0=5days09:39:56
3767214----140785-----101806--ppp0=5days18:25:50--=
Total Corrected CRC's=7030 Uncorrected:ES-1863 SES: 89

but from 08:47 to 19:04 today =1371383 Corrected CRC's , 36640 Uncorrected ES,& 29470 SES
and todays Tbbqm
My ping And for some reason the router hasn't reset it's ppp for over 6days, so maybe it was down to the exchange kit or it had been set to do it after a pre determined time ?

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