ADSL suddenly not synching

G

GPSJane

Well-Known Member
Joined
Jun 14, 2009
Messages
482
Reaction score
1
Location
Johannesburg
I know there are lots of posts about these things but I don't really see an exact answer.

I have had a 4Mbs line for years. I have had only minor problems along the way and always gotten somewhere just a little below maximum speeds. I am quite far from the exchange so I am happy with the speeds I have been getting. Recently they were a little lower at about 3.5Mbs.

Then suddenly one day my Netgear DG834GT modem disconnected and would not reconnect. I had a Telkom Mega 100WR2 handy and this connected fine so I assumed it was the port on the Netgear. Then a few days later I started having problems with the Mega. It drops the connection and tells me the line is not synced. Or it syncs at incredibly low speeds (like less than 1Mbs) but never the same speed twice. Then it will randomly connect at very fast speeds but this never lasts for a day. I haven't managed to connect the Netgear but I think if I left it on it would eventually just like the Mega.

I have logged numerous faults with Telkom but they keep 'resolving' the fault without fixing it. I even had a technician in my house who told me there is nothing wrong with my line.

What do I do?

My stats at the moment:


Connection Status Connected
Us Rate (Kbps) 503
Ds Rate (Kbps) 721
US Margin 7
DS Margin 6
Trained Modulation ADSL_G.dmt.bis
LOS Errors 45
DS Line Attenuation 60
US Line Attenuation 40
Peak Cell Rate 1186 cells per sec
CRC Rx Fast 8816
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path

Yesterday my attenuation was 50/23 and the day before 53/25

I guess 'margin' is noise margin?
 
I tried to post this last night but the internet connection was so crappy it never submitted.

My stats are as follows now:

Connection Status Connected
Us Rate (Kbps) 503
Ds Rate (Kbps) 4092
US Margin 10
DS Margin 6
Trained Modulation ADSL_G.dmt.bis
LOS Errors 0
DS Line Attenuation 54
US Line Attenuation 33
Peak Cell Rate 1186 cells per sec
CRC Rx Fast 1334
CRC Tx Fast 0
CRC Rx Interleaved 0
CRC Tx Interleaved 0
Path Mode Fast Path
 
Where are you located?

I heard rumours that Craighall Park upgrades caused a lot of customer issues with non-Telkom-supplied ADSL modems/routers.
 
@GPSJane: Unfortunately can't offer much help but I'm going to following this thread in the hope that there's something I can try that I haven't before.

I seem to be experiencing a similar problem and same story - Telkom techies say my line is "fine" yet it randomly decides to lose sync. My downstream SNR margin fluctuates continuously yet upstream SNR margin remains constant. Did the usual - tried different modems (including a brand new one), unplugged *every* electrical device apart from the adsl stuff to rule out electrical interference, different pots (?) filters and even did a few port resets/refreshes(?). Nothing has helped so far. Now I'm considering cancelling my adsl - definitely not something I want to do but it's just not feasible anymore.

It's like owning an expensive sports car that randomly cuts out while you're driving it. It's just frustrating and ultimately pointless.
 
To any people in this thread wo are experiencing similar, sudden problems, please post some useful details, such as number range you are on, and when (what day) the problem started.
 
Your downstream SNR margin is quite low at 6dB, for your particular line speed. What this means is that there is very little margin for noise, so a little interference will cause your line to drop sync.

I'm having the same issue on a 2meg line with a 63dB attenuation and 7dB SNR margin. And I'm being given the usual Telkom runaround for a weeks now.
 
ranger said:
To any people in this thread wo are experiencing similar, sudden problems, please post some useful details, such as number range you are on, and when (what day) the problem started.
Click to expand...

Good idea. I'm on 011 485 xxxx. Orange Grove exchange (iirc). Can't remember exact date problem started but funnily enough it was a day or two after Telkom started their 384k to 1meg upgrades - I remember that much. I don't think my problem is related to the upgrades though. Have had a stable 4meg line for +2 years and then at some point earlier this year my line was syncing at 6meg but still very stable. I've 'downgraded' to syncing at 5meg but hasn't helped as the problem seems to be the ever-changing downstream SNR margin.

I'll post modem stats later when I get home.
 
I've started experiencing the same thing on my 011-234 xxxx (Sunninghill exchange) line Sunday +-15:45.
I'm on a 10mb line and it's been running fine since I connected a few months ago. 'Normal' SNR was 12db to 15db (I know, quite low, but it was quite stable). Since Sunday, this has been 6db and the connection would not last for longer than 2 hours. The modem would then try to reconnect until it eventually syncs at 10mb again with numerous 'connections' (random numbers ranging between 4mb and 6mb) established in between.
 
@GPSJane have you any noise on your telephone if you listen on the line (pick up the phone dial 0 and listen for crackling).
IMO fluctuating SNR is an indication of a fault on the copper pair but could be caused by other factors to like induced noise from another line in the copper cable.
 
I checked the phone line when it started and did not hear any noise. I don't actually have a phone on this line so I will have to go listen again with a borrowed phone.

I removed all filters and don't have any other equipment.

I'm in Weltevreden and my DSLAM is at Clearwater.

I can't remember the number but I think it's 011 475....

The Mega 100WR2 is a Telkom supplied router.

I think the Netgear is actually damaged because it won't connect at all but the Mega is connecting (I tried the Netgear for a while). This probably caused by the same thing that caused these problems because the Netgear stopped and these problems started at the same time. I have bought a new modem so I will try that too when I get it.
 
Another note: my brother was getting terrible attenuation and SNR values. He logged plenty faults but Telkom kept saying they have fixed the problem with no improvement.

He eventually climbed onto the roof where the cables are are pulled everything out. He then rewired the entire place with a single cable and connected it to the main incoming line with the correct boxes etc.

He now has a stable 10Mbs line.

Unfortunately my lines all run underground so it will be very difficult to do the same but we are considering trying it!


Another thing: someone else in my complex has an ADSL line that is stable at 4Mbs i.e. they are the same distance from the DSLAM. Something must have happened on the day that things went fubar that only affects me. I think the date was around mid-September but I am not completely sure.
 
Hi there, It may be the upgrades taking place, but I would try another modem first to eliminate that. The borrowed phone is good to do an audio check on the line. You could also try placing a voice fault rather than a data fault as Telkom generally responds to those faster.
Your margin figures look a bit low but should give you 3500 as a sync. I use a link on this site to get the figure based on the information you gave

Good luck. Regards

Tim
Follow me on @TechXperTim
 
How do I tell where upgrades are taking place? A closer DSLAM would be nice...

I think I have been logging voice faults. Or mix of both.

I got the D-Link and the problem is identical. The problem is not the modem.

Since I did listen to the line when this started, I doubt that's it.

It makes me cross that Telkom just can't do anything about this! And when they come out I magically get full speed for the duration of their visit and then 5 minutes after they leave it drops the connection.
 
Hi There,
I don't know of any way that you can see which exchange has been done and which hasn't. Mine I know was done in the last week as I am now syncing at home at higher speeds.
I would ask them to reset your port which they should be able to do with you on the line. But with the margin so low I suspect the fault is in the cable.

Regards

Tim
 
Could also be a faulty card at the exchange, but Telkom normally only replaces it if the same problem is reported 3 times or more, as the card is quite expensive (or so I was told when it happened to me). Just keep all the fault numbers logged.
 
Trixanno said:
I've started experiencing the same thing on my 011-234 xxxx (Sunninghill exchange) line Sunday +-15:45.
I'm on a 10mb line and it's been running fine since I connected a few months ago. 'Normal' SNR was 12db to 15db (I know, quite low, but it was quite stable). Since Sunday, this has been 6db and the connection would not last for longer than 2 hours. The modem would then try to reconnect until it eventually syncs at 10mb again with numerous 'connections' (random numbers ranging between 4mb and 6mb) established in between.
Click to expand...

For my line 011-234-xxxx the exchange reports max available speed as 4Mb. But I am have terrible line sync issues of lately. Constant drop outs especially in the evenings. SNR Margin (Downstream) between 3.1db - 6.2db.
 
You must log in or register to reply here.
Back
Top
Sign up to the MyBroadband newsletter
X