ADSL cutting out, yet again

K

Kasyx

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*sigh*

Again, I am having issues with my ADSL line. This time it appears that my line cuts out (my router actually stops syncing) whenever it rains. Considering the amount of rain lately, you can imagine how often I am offline :(

However, today, a rainless day, my ADSL was disconnected completely. So I phoned Telscum and after the obligatory 1 hour hold time I got through to someone (Hazel, she said her name was), who was completely unhelpful in every way. Except, of course, for wanting to downgrade my connection. Never mind the fact that I have been syncing at 4096/384 perfectly for over a year, for some reason she got it into her head that either the exchange, or my house, had moved further away in the last few weeks. I told her no way. This is a line fault.

She then asked if I was able to browse again, which, of course, I now was. She told me I should phone for a line test when my line is actually down. I told her I had phoned around an hour ago, this is that call. I have now been fortunate enough to be blessed with a Reference Number, which will come in useful when they contact me about it. What this means, of course, is that my Reference Number is completely useless.

Anyone else having similar issues? Not with Telkom, with their sorry excuse for broadband.
 
I have the exact same Issue.

Every single time it rains or there is a storm, my ADSL constantly loses sync and reconnects every 5mins.
If I pick up the phone, the line sounds terrible. :(

I have had Telkom over numerous times, saying they've resolved the issue, but it just continues. They have tried rewiring the box on our telephone pole without success. However I am still sure that there is a problem at the local exchange or somewhere on the line itself, where water could get in or something else could happen.

I am also on a 4096/384 connection, which remains perfectly stable throughout winter, but as soon as summer arrives and we experience rain, bye bye ADSL. :(

If there is any method for solving, please let us know :(
 
I have the same problem, but peppercorns when I picked up my phone my line sounded terrible too, it turned out to be a faulty ADSL port filter on my telephone line , replacing it fixed the ''noise'' problem, but since heavy rains my modem connects and disconnects for 30 secs from 8 am to around 7 pm :|
 
Noise on your line can be attributed to what 5 things I think?

1. Your filters are faulty.
2. The cable linking your telephone to the pole outside your house cam be rusted through. (What happened to me recently, had it swapped)
3. The local exchange is screwed.
4. Your line to the exchange is screwed.

AND LASTLY,

5. The last technician to your house didn't do his job.
 
Happens to me quite a bit. First thought it was my modem but now I see that Telkom are having problems. Have problems rain or shine.
 
One of DSL's major problems is water logged lines, or moisture at connection points which alters your signal.

It happens. Even in the States.
 
Welcome to South Africa

I have the excact same problem when it rains my line goes down.

I personally don't think Telkom can fix the problem they need more specialist.

What we need to find out is wheter we qualify for discount because they can't provide us with a real service so I personally think they can't expect us to pay line rentals if they can't even fix small problems like water.

Man you can only laugh about it.
 
with my last serious case - the specialist told me - the biggest problem of these "wet" lines is that they are using "paper" (underground) to cover the joints...within the jelly...

now that jelly is supposed to be waterproof.

guess what water does to paper :)
 
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OK.....as an ex Telkom technician I can tell you the following:

If your DSL modem disconnects (or loses sync) on a regular basis....insist on a line test......in fact insist on the results of that line test (even though it might not make any sense)

Most modern cables in Telkom are PVC but can be influenced by moisture or other systems that carry higher voltages.

The test should reflect:
-absolutely no Earth potential
-no more than 12v contact (foreign -ve)
-also watch out for how many phones are connect to your line at any stage - The more phones, the higher the line capacitance.....the easier it it for your modem to lose sync by not understanding the incomming carrier signal.

I too have a 4meg line and had frequent disconnects at a stage.....insisted on a line test (through the supervisor as the "Kelly personel" operator insisted that because I could browse the net all was Cool)......The test result showed a -38v contact that went to -49v when it rained. note: Audibly I could not hear any problem during normal conversation......somtimes you can here a slight "cross-line" with this type of condition.

A line fault was reported and a spare pair of wires was used to bypass the fault......then the "Kelly personel" chic phoned me back to write the fault off.....once again....insist on the results of a second test....if all is clear then allow them to write the fault off

These people are stats driven.....so its important not to allow them to write the fault off if it is not clear.....you will get higher priority on the system a more people will try to resolve your problem

Incidently.....The testing system (LTS) CANNOT perform a test while you are talking on the line, they have to tell you to put the phone down then ring you back with the results.

Hope this is of help to you guys!
 
Just spoke to the techie. My Contact is fine and there is no earth potential. The last guy who came bypassed the fault and that sorted out the cross-line, but the ADSL is still causing trouble.

What does it mean to "divert the E-Side of the cable"?
 
"Divert E-side" means the tech has changed or diverted your pair of wires between the Exchange the SDC (street distribution cabinet - the big box on the road side)
If the line is clean then my next option would be to check how the modem responds being the only connected device....ie disconnect all other devices, fax machine, phones, line filters.
I the problem persists.....the techs at the help desk can do an error check...sometimes faulty DSLAMS (ADSL Exchange equipment) can cause errors but this will affect a few users.
Line distance also comes into play.....between 4-5 km from the exchange the line resistance will attenuate the signal significantly. I use somthing like Google earth to approximate the distance to the exchange...the route of the cable mostly follows main roads....never a direct straight line.
 
My house is around 500m from the exchange. The support desk has done about 6 line tests, all of which came back clear :( The only other thing connected to the line is the one phone. Any clue what else could cause my SNR to drop by over 10dB?
 
Hmmm, the saga continues.
500m away in field trials for ADSL we were able to get 8Meg/sec 5 years ago.....being so close even a "dry joint" or a loose connection would not have a serious impact.
Techs somtimes carry a pulse echo fault locator with them. This, when connected to the line, will give a graphical display of the quality of the line. Any "blip" up or down indicates a loose connection or low insolation. If the tech has such a thing its very helpfull as it esimates a distance to the fault.
However.....your problem sounds more and more like an equipment failure....either swapout the modem....or get them to change the DSLAM port.
more than that....I know not!
 
What router are you using? You might be able to get some useful diagnostic information if you can telnet to your router and issue these commands from the command line interface - wan adsl linedatan OR wan adsl linedata near OR wan adsl linedataf1 OR wan adsl linedata far.

If you post some linestats from your router somebody may be able to help you more. Is there any noticeable increase in the router downstream or upstream Tx powers between when the line is wet and when it is dry? Have you looked at the tone data from your router to see if there are any problems with crosstalk or any dead spots particularly around the pilot (tone 64).
 
DRY LINE (not raining)

I will post the statistics for my line when wet the next time it rains.

wan adsl linedatan:

Code: 
relative capacity occupation: 65%
noise margin downstream: 14.0 db
output power upstream: -1.-5 dbm
attenuation downstream: 36.5 db

wan adsl linedataf1:

Code: 
relative capacity occupation: 46%
noise margin upstream: 13.0 db
output power downstream: 9.5 dbm
attenuation upstream: 18.0 db
carrier load : number of bits per symbol(tone)
tone    0- 31:00 00 00 02 23 55 66 77 77 77 77 66 65 54 20 00
tone   32- 63:00 00 00 02 23 44 56 67 78 88 89 98 99 98 49 99
tone   64- 95:09 99 99 99 88 74 42 88 99 88 88 88 87 88 76 26
tone   96-127:78 77 77 65 76 67 65 40 32 57 77 77 77 67 77 76
tone  128-159:24 67 77 77 76 77 77 65 40 24 66 65 67 67 77 77
tone  160-191:76 54 67 77 77 76 77 77 66 53 25 66 66 56 43 55
tone  192-223:55 54 30 34 44 43 43 44 33 33 30 02 23 33 33 23
tone  224-255:32 00 33 20 33 33 32 33 34 33 33 32 02 33 33 23

Current Sync:

Code: 
Upstream 	384 kbps
Downstream 	4096 kbps
Noise Margin (Upstream) 	13.0 db
Noise Margin (Downstream) 	14.0 db
Attenuation (Upstream) 	         18.0 db
Attenuation (Downstream) 	36.0 db

Hope this helps :)
 
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Problem 1
Here is your bits per tone plot. It seems that you have a lot of crosstalk on your line as the plot is very ragged - the peak heights are supposed to follow a smooth curve. I would guess that the only way to fix this problem would be to get a clean pair from the exchange to your distribution box - I think this is called an F2 pair. Maybe Leftfoot can comment more on this. When it rains the crosstalk should get worse due to the extra moisture but you should check exactly what is happening as there may be additional problems when the line is wet such as dead spots in the spectrum.
http://i217.photobucket.com/albums/cc189/Hinapina/image001-3.gif

Problem 2
Your downstream attenuation is being reported as between 36 and 36.5dB. This would mean that you are approximately 2.65km from the exchange (i.e. 36.5/13.81). You mentioned 500m above - are you possibly confusing the distribution box with the exchange? Are you sure about your distance from the exchange?

Would you be able to get some plots of your wet and dry downstream noise margin over time using routerstats?
http://www.vwlowen.co.uk/internet/files.htm

If you can't get a better pair from the exchange you could also try to reduce your line speed to 2Mbps. This will increase your downstream noise margin and possibly fix the problem when it rains.
 
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I'm not getting confused, I even double-checked where exactly the exchange was with the Telkom tech today. I have just done a drive-by on it in my car to measure the rough distance. Around 650m, which would have made sense last month when my Attenuation was at 19dB, but for some reason since the beginning of November it has jumped up, almost as if they moved the exchange in the middle of the night one night...

I will check that program out and try get some plots for you. Thanks so much for the help :)
 
Cant say I have heard of an F2 pair. Suffice to say that Telkom try to build in 25% spare capacity for faults and future growth.

A standard cable cable pair has:
- an E-SIDE (from Exchange to SDC-Street distribution cabinet
- a V-SIDE (from SDC-Street distribution cabinet) to the terminal equipment

The E-side is usually pressurised to resist water penetration
The V-side is not pressurised an has many connect points and potential problem sources. (trees rubbing through insulation, animals eating insulation, bats urinating and corroding connections...the list goes on)

9 times out of 10 the problem will be on the V-SIDE

In order to change your pair the whole way the tech needs to divert in at least 3 places (the Exchange -MDF, the street box -SDC, and the Local Distribution Point - DP).....can also be as much as ten points if your line in aerial cable fed.
 
I never had problems with my ADSL line but a few days ago it started!

The line works 100% until it starts to rain OR the wind blows, then you can hear a scratching like noise on the line (sounds horrible). I've walked out front to our local DB and stripped the wires and put new CAT5e between them, it used to be what looks like glorified lamp cord that connected the two wires (we live in a complex and Telkom has a thick black wire that comes in and connects to the complex local wiring, the complex wiring is CAT3 and the telkom wire looks quality also, so it's basically just the lamp cord that sucked, no rust tho).

EDIT2: Just as a note the actual DB thing (if you can call it that, it's basically one wire coming from Telkom connected to a chocolate block and a wire coming from the complex connected to another chocolate block with the cheap wire to connect them) isn't Telkom property, it belongs to our complex so I wasn't messing around with their wiring..

Unfortunately it didn't fix the problem, my upstream SNR went up quite a bit but every now and then when the wind blows there is still the disconnects and terrible scratching noise (to the point where you can barely hear the dial tone and dialing also becomes impossible, intermittently)

How do I get this line test thing done, I logged a fault today but they just sms'd me the fault number and promised someone will get to me although I'm not much in the mood for sitting around waiting....

Also very strange but I can hear these weird sounds on the line when the connection is dropped that sounds like syncing but I have 2 different filters and both worked fine for over 2 years now and suddenly I can hear this weird noise when it re-syncs. Coincidentally disconnecting everything still causes frequent sync loses so even if the filters are suddenly broken they still don't cause the problem...

EDIT: also with the ADSL modem plugged in, if I meter my telephone line with a multimeter it reads 7volts DC, is that normal?
 
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