Huge fluctuations in SNR

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Mark051

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Hi All

I'm currently experiencing stability issues with my ADSL Line.
Ive noticed that the problem occurs only when the SNR decreases to below 6.

My problem is that the SNR fluctuates hugely, and it does this very unpredictably.

MY line stats at the moment are as follows:

ADSL Link Downstream Upstream
Connection Speed 6144 kbps 639 kbps
Line Attenuation 40.0 db 24.0 db
Noise Margin 9.9 db 11.7 db

I have perfect connection now, but the noise margin very often reduces to 5, in which case I lose connectivity.

What could be causing these fluctuations and also how can I prevent the noise margin decreasing?
I have tries disconnecting the Phone etc, but does not seem to make any difference.


I live in a block of flats, so I suspect there's something affecting the line outside of my unit?

I hope someone can offer some advice?
Thanks
 
Does it fluctuate at certain times, eg when it rains? Or just randomly at any time?
 
Sounds like bad wiring (electrical/telephone) or appliance (toaster/geyser/aircon/...).

Check everything in your flat first.
When the SNR goes bad again... wiggle connectors (replace?), tug wires (replace?), turn off as much trip switches at the power box.
Recreate the problem at will from inside your flat, failing that, phone Telkom...

GL!
 
Fluctuates completely randomly. I've tried to identify what could be causing it, ie rain, vacuum cleaner etc but dont seem to find any anything

I've tried all the above, doesn't seem to change anything - Thats why i think its something in the building, but outside my unit?

The Telkom Technician has been here, but wasnt able to find anything.
 
Mark051 said:
Fluctuates completely randomly. I've tried to identify what could be causing it, ie rain, vacuum cleaner etc but dont seem to find any anything

I've tried all the above, doesn't seem to change anything - Thats why i think its something in the building, but outside my unit?

The Telkom Technician has been here, but wasnt able to find anything.
Click to expand...
I had a similar issue long ago. Turned out to be a loose connection at the SDC box on the sidewalk.
Alternatively, also check whether the phone line (inside your unit) runs near any power lines. Also double-check your pots filter.
 
Ja, then it outside unfortunately, and if it's random, then it becomes a real pain to troubleshoot. Techie can't fix what he can't see.

But next time, ask him to disconnect and reconnect all connections he has access to.
Don't allow Telkom to close the ticket, and trust me, they try to close those tickets... and they can get very crafty at it.
When they ask you anything, just reply "DO NOT CLOSE THE TICKET, and <answer>".

You don't hear any noise on the telephone during SNR season do you? AND you have tried a alternative modem (including alternative power supply)... right?

GL
 
6db SNR...........synch but service affecting. Anything lower and its going to drop the link. 12db and higher is ideal. You might find the service will auto adapt and drop your synch rate until the 12db SNR is maintained. Which means stable service.......but slow speed.

Follow madrynn's advise and isolate the equipment inside. If problem still persists.......call Telkom.

Is there any static or hum on the line?
 
Thanks all for the replies!!!

I've tried a couple of routers, and the current one I'm using (Telkom Netgear Router) gives me the best stats.
Haven't had any luck yet, but I'll keep trying.

Thanks
 
Mark051 said:
Hi All

I'm currently experiencing stability issues with my ADSL Line.
Ive noticed that the problem occurs only when the SNR decreases to below 6.

My problem is that the SNR fluctuates hugely, and it does this very unpredictably.

MY line stats at the moment are as follows:

ADSL Link Downstream Upstream
Connection Speed 6144 kbps 639 kbps
Line Attenuation 40.0 db 24.0 db
Noise Margin 9.9 db 11.7 db

I have perfect connection now, but the noise margin very often reduces to 5, in which case I lose connectivity.

What could be causing these fluctuations and also how can I prevent the noise margin decreasing?
I have tries disconnecting the Phone etc, but does not seem to make any difference.


I live in a block of flats, so I suspect there's something affecting the line outside of my unit?

I hope someone can offer some advice?
Thanks
Click to expand...

Evening, SNR and attenuation often relates to noise on your line.

Is there any noise on your telephone line? (a crackling sound).
 
No, No crackling on the line.
SNR seems to be better in the evening.
 
If your SNR is fluctuating it's likely loose/faulty wiring somewhere.Log a fault and keep logging faults until it's resolved.
 
I'm having this exact issue. Just started right now for the past couple of hours. My line doesn't stay up longer than 3mins or so, then dies.

Attenuation stays the same, but my SNR fluctuates to below 10, and then reconnects around 23 or so. I've even seen my router showing -3SNR, whatever the hell that means. Not sure what the heck to do.
 
I found the fault!!!!!!

I live in a block of flats, with approximately 50 units.

A couple of weeks ago, the intercom system was upgraded, and with that my SNR improved ;).

I can only assume that the intercom and the telephone/ADSL share the same lines in the building, and by upgrading the intercom, the telephone lines were inadvertently upgraded at the same time.
 
Think I'm having the same problem. Anyone got any ideas how to get it fixed / diagnosed? Its not intercom for me but same issue -- SNR going from 9db to negative. This repeats every few seconds all night long (not sure about day time yet!)
 
richjdavies said:
Think I'm having the same problem. Anyone got any ideas how to get it fixed / diagnosed? Its not intercom for me but same issue -- SNR going from 9db to negative. This repeats every few seconds all night long (not sure about day time yet!)
Click to expand...

Try connecting without a filter
 
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