volt/amp readings using multimeter on ADSL line

I moved into a house (CPT) with a dodgy line - worse when raining

I would experience the same issues as this.

After telkom came out twice, changing to the next 2 clean copper pairs available in my strand, we ran out and had to investigate further.
I Dug it up with the technician "carefully" and found a previous spade had fleshed just about every strand.

He replaced the line running to the house completely - now i aint got any issues.

My advice - put a spade through the line and log a fault as usual.
 
-cut 5cm new of dropdown wire
-new choc connector
-new cable from choc to 2xrj11 wallbox

-shortened that cable from .5m to .1m

NO DIFF

had 18 disconnects so far today - and this on my reduced 512 from 1024 profile.

all my cables are air cables..nothing underground for 300m
 
You're quite sure that there isn't an intermittent break in the phone line. Today was very windy which might explain the multiple disconnects although the noise would presumably also be higher. Have you tried monitoring the DC voltage on the line with nothing else connected with a cheap multimeter. If there is a break the needle should move towards zero every now and then (not ideal but should be easy to do). If you know a bit of electronics a simple power failure latching device would be preferable.

If the problem seems to be getting worse this may be a good thing as it will probably stop working completely quite soon particularly with the storms approaching. I hope that you put back all your lightning protection! Take a look at that the thread "My woes with 384" - one poster claims that his ADSL was badly affected by a radio/alarm clock device. The only appliance that I can think of that switches on and off regularly is a fridge so it might be wise to check these also.
 
Oupa I'll be straight with you - after looking at those plots - your line is beyond gone, there def is a cable break (rupture and possibly water in the line)
I think unless you take some drastic action - you are going to be stuck trying to get stable every 10 mins for the rest of your days.

Have you thought about applying for a second line?

A) Possibly just rule out the current line - I realise you will be getting the same ****ty 40 yr lines, but sometimes 2 new copper strands can work a charm.

B) I did this albeit just to get the technicians out to my place - from where i hi-jacked them and we fixed my problem.

And i personally monitored every join the made, queried every beep, buzz, whizz and bleep the testing equipment made, and would not let them leave untill they had verified themselves that my line was stable (that meant them looking at my plots)

I sat with the tech at the manhole on the street corner going through 10 000 000 strands trying to find some good ones - they can be very accommodating - you just need to get them to your premises and u need to be prepared :) ... my 2c
 
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Yotch said:
You're quite sure that there isn't an intermittent break in the phone line. Today was very windy which might explain the multiple disconnects although the noise would presumably also be higher. Have you tried monitoring the DC voltage on the line with nothing else connected with a cheap multimeter. If there is a break the needle should move towards zero every now and then (not ideal but should be easy to do). If you know a bit of electronics a simple power failure latching device would be preferable.

If the problem seems to be getting worse this may be a good thing as it will probably stop working completely quite soon particularly with the storms approaching. I hope that you put back all your lightning protection! Take a look at that the thread "My woes with 384" - one poster claims that his ADSL was badly affected by a radio/alarm clock device. The only appliance that I can think of that switches on and off regularly is a fridge so it might be wise to check these also.
Click to expand...

-negative on the break detection - if this was back in the ISDN days - i would say SPOT ON - i did receive this problem back then ...got sorted somehow..

-but its ok-ish now : i shall later try to capture some audio samples (building a MASSIVE report - with tons of pictures/graps/sounds ect)

-every 1 in 10 calls or so i can hear a faint noisy line (scratches (inconsistent)) - other 9/10 times totally quiet.

-there is 1 thing worrying me: - when my ADSL routers (ALL OF THEM) resyncs - i can HEAR them on the phone.

-and the thing that when a ringing phone is picked up - in about 50% of the times causes a sync los - that worries me too - thats why the filter is supposed to help?!

-i've seen when the wind blows : it either has noise on the line or its 100% clear.....its like hmmm the consistancy factor again.

-in terms of storms - we had a HUGE HUGE electrical storm last year about sept....telkom did say that 1 leg had been damaged and they repaired it - everytime a tech pitches up i do bring this under their attention - they have this small graphical device that checks both legs and for shorts - it shows clear.. but then again this problem has been with me since i got adsl in march of 2003..just been getting worse and worse

-as per power/clock issues - i also did a test on friday - turned EVERYTHING off (gate motor ,lights , security systems+lights , aircons , other pcs, other switches , wifi devices , pool pumps , radios ,tvs ,ect!!) - no diff

Also - all these tests have been done on either direct ESKOM power - or with a Mecer 600VA ups modified plug - so that it runs directly from it. Also have an APC lineinteractive ups with modified plug - no diff.

so i dunno
 
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plenty said:
Oupa I'll be straight with you - after looking at those plots - your line is beyond gone, there def is a cable break (rupture and possibly water in the line)
I think unless you take some drastic action - you are going to be stuck trying to get stable every 10 mins for the rest of your days.

Have you thought about applying for a second line?

A) Possibly just rule out the current line - I realise you will be getting the same ****ty 40 yr lines, but sometimes 2 new copper strands can work a charm.

B) I did this albeit just to get the technicians out to my place - from where i hi-jacked them and we fixed my problem.

And i personally monitored every join the made, queried every beep, buzz, whizz and bleep the testing equipment made, and would not let them leave untill they had verified themselves that my line was stable (that meant them looking at my plots)

I sat with the tech at the manhole on the street corner going through 10 000 000 strands trying to find some good ones - they can be very accommodating - you just need to get them to your premises and u need to be prepared :) ... my 2c
Click to expand...

About 2 months ago - when i had some serious hope , telkom had a 3rd party cable contractor doing about 14 000 joints over - they detected water on the line...

I was soooooo mad that day when they finally "finished" - the telkom cable manager phoned me : " Sir sir , we are done , is your line up now? " i'm like " erm it has never been a question of not having service running , but the intermittend los of signal problem" .

My line had been connected for about 45 seconds before he phoned - and as we were speaking my ADSL reconnected only to immediately drop sync 5 times in a row...lol , shame - I told him : " Please get in your car and get over here - its not working correctly and i can prove it to you"

He wasn't taking my story very good - he said its impossible - line tests 100% clear. So he send one of the "telkom cable department" techs.

When he came around - he had shown to me clearly he had NO experience with ADSL (didn't understand my situation ) - and blaimed it on the "DATA DEPARTMENT" - he said they cannot work together (CABLE AND DATA depts).

so when its a cable problem - adsl tech calls cable .
adsl problem - cable dept phones adsl .
i bet ya if those depts would work together they would surely solve more serious issues.

the quest continues.
Nutz
 
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Your downstream attenuation figure of 49dB is quite bad though. I wonder if it ever increases above 50dB. See below. The upstream noise margin also seems marginal at 12dB. I think that you can improve this figure though by changing the coding gain in your router. See link above about coding gain. It does seem that your figures may be acceptable for a line length of ~4km.

Here is a guy in Australia who has managed to get his ADSL working with a downstream attenuation figure of 49.5dB by tweaking his Billion -
Reduce the coding gain 7 > 0
Increase the TX Attenuation 0 > 14db

http://forums.whirlpool.net.au/forum-replies-archive.cfm/502053.html

"Noise Margin (AKA Signal to Noise Margin or Signal to Noise Ratio)
Relative strength of the DSL signal to Noise ratio. The higher the number the better for this measurement. In some instances interleaving can help raise the noise margin to an acceptable level.

6dB or below is bad and will experience no synch or intermittent synch problems
7dB-10dB is fair but does not leave much room for variances in conditions
11dB-20dB is good with little or no synch problems* (but see note below)
20dB-28dB is excellent
29dB or above is outstanding

* Note that there may be short term bursts of noise that may drop the margin, but due to the sampling time of the management utility in your modem, will not show up in the figures.

Line Attenuation
Measure of how much the signal has degraded between the DSLAM and the modem. This is largely a function of the distance from the exchange. The lower the dB the better for this measurement.

20dB and below is outstanding
20dB-30dB is excellent
30dB-40dB is very good
40dB-50dB is good
50dB-60dB is poor and may experience connectivity issues
60dB or above is bad and will experience connectivity issues"
 
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[OUPA]MrNutz;1195883 said:
on my telkom 5102G i get

SNR 32
line attenuation 54-58
Click to expand...

That line attenuation figure is terrible and your SNR seems to jump up and down. If Telkom can't improve on these figures then you are going to struggle to get a reliable connection. If nothing improves you will probably need to get a router that can handle very poor quality lines. I have seen an Alcatel SpeedTouch 330 on sale if you are interested - one of their routers would probably be a better bet though.
 
I'm having the same problem with my line, its been a month like this and 4 telkom visits and all they do is just test that they can see a web page, they don't check the stability of the line, I'm even thinking of ordering a second line, I have a telkom 5102g router and when I run the diagnostic screen my primary domain name server always fails , I don't know if that contributes to the constant loss of connection when surfing the net
 
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What kind of linestats are you getting i.e. attenuation, SNR etc.?
 
Yotch said:
What kind of linestats are you getting i.e. attenuation, SNR etc.?
Click to expand...

Description----------Downstream ------ Upstream

SNR Margin-----------: 33.5 --------- 14.0 db

Line Attenuation-------: 29.5--------- 15.5 db

Data Rate--------------: 1024------- 384 kbps

my IS accounts don't even work no more cause the modem cant get the primary domain name server, but it does show that the adsl is working and I even get allocated an IP address
 
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Apart from the upstream SNR margin figure the rest seem reasonable. You could try to improve this figure by changing the coding gain as described above. Would it be possible to borrow a Netgear DG834GT and get some bin plots using DMT?
 
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http://fremnet.net/article/216/adsl-theoretical-speed-calculator

with 5102G telkom

Enter your Downstream attenuation (dB) 53
Cable Loss (dB/km) – Default 13.81
Attainable Rate (ADSL1) – kbit/s 4153
Attainable Rate (ADSL2) – kbit/s 4321
Distance to exchange (Meters) 3838

with netgear 834

Enter your Downstream attenuation (dB) 48
Cable Loss (dB/km) – Default 13.81
Attainable Rate (ADSL1) – kbit/s 5329
Attainable Rate (ADSL2) – kbit/s 5989
Distance to exchange (Meters) 3476

interesting observation
 
@OMN: Sounds like you will be having a lot of fun over the next few days. Post the bin
plots these should be very interesting.

The attenuation is supposed to remain relatively constant so there may well be a line fault unless there is some very strange interference problem. Are you sure you can't hear any noise on the line because that attenuation seems to be changing very rapidly? If you have an analog multimeter it would be interesting to monitor the voltage across the line (with the router disconnected) to see if it varies.
 
Yotch said:
@voyt: Good point! I was under the impression that Telkom was using Marconi and Alcatel DSLAMS but it would be interesting to get feedback about this from Telkom themselves. The Speedtouch used to be manufactured by Alcatel and then the business was sold to Thomson so it's not impossible that one of these models would work better with an Alcatel DSLAM. Is there any way to determine the type of DSLAM that you are connected to while you are online?
Click to expand...

According to my Telkom Spy they only use marconi dslams now. Phased out the alcatel systems.
 
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