volt/amp readings using multimeter on ADSL line

It might be some type of capacitance effect - i.e. when the charge on the capacitance increases too much it sets the process in motion. I think that American guy that I posted about also reported this type of behaviour. I'm going to read his story again.

Try to test any lightning protection devices along your line to the exchange. They could also behave very strangely if they were damaged.
 
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@OMN: You should also get the tech to look at those two frequency dips at 586 and 656 - this will also start to cause problems if you try to connect at speeds exceeding 4Mbps. It may be possible to also fix this at the same time by either finding the problem or by switching to a better pair of wires. It seems that you may actually have two different problems on your line.
 
tech hasn't been here

but - i recall that they have this silver suitcase tester with analogue dail switch- with 3 digits - where they listen for noise - i never asked what it was for..

but now with the DMT - i would recon its a sub 1000kHZ AM noise tester?
 
@OMN: You should now be able to get the noise problem fixed without too much trouble.

Those two dips could mean that you have a bridge tap on your line i.e. an unused extension on the cable. Maybe they can remove it or find you a better piece of cable.

Have you tried to listen carefully to the phone line *without* using any microfilters. It's possible that there may be a noise there but that the ADSL microfilters are filtering it.
 
i'll have a listen 2morrow morning with everything unplugged

Telkom is pi$$ing in my pool again.....:mad:

on the 22nd of Aug I logged a call - The lady yesterday , at 375375 , told me it was closed on the 23nd of Aug - i asked her - by who? she just gave a name of a lady - not even comments given..

now i have logged one yesterday - and they Telkom CT phoned me and said a tech is due today - nothing yet - starting to get a bit peeved. This is a town !@#!@# not a city....under which tree/bush is he/she sleeping already.

and on top of that - i have a bloody strep throat.
 
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@OMN: I'm optimistic that you have finally found the problem and that it can be fixed quite easily. If they had come in August it might not have been so easy to detect. Let's hope that it all works out properly. I have found that if you offer the technicians cooldrinks and snacks they generally put in a bit more effort!

The noise seems to be triggered some time after the router is reconnected to the telephone line and disappears again after another reconnection. This really sounds like a faulty surge/lightning protector on one of the telephone poles that starts to switch on and off (oscillate) at the 48V line voltage after a certain amount of charge has built up or some other malfunction in a piece of Telkom equipment like the DSLAM. Earlier you were under the impression that it might somehow be related to crosstalk, the time of day or some kind of AM interference on the line which would be much harder problems to solve. Hopefully your line should be running smoothly by the weekend!

I hope that the throat problem goes away quickly.
 
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hehe. feels like my tonsils were removed all over again with this throat pain haha...

anyhow thanx a stack for your inputs...i sincerely hope they pitch up and it gets sorted once and for all
 
what can i say.....

a telkom adsl tech tunes me over the phone - SIR sorry - your graphs behaves like it does because the server is busy during daytime ..

they are yet to arrive.
 
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1st thing done - he shorted my point to exchange - resistance measured 867 ohm - max allowed 1000 ohm...

2nd thing done - disconnected the voice leg (wire) from my setup thus only currently on ADSL - monitoring until 8am tomorrow.

i'll post screenies later
 
Good luck! seems they are very bad at fixing intermittent faults and even worse at actually listening to what the fault symptoms are....
 
2nd objective status update - negative - disconnecting the ANALOGUE port as they call it / or just plainly put 1 less wire - didn't do JACK diff for me..

so i now have ADSL running - with no voice service - and its exactly the same...

screenie:

http://i210.photobucket.com/albums/bb147/jannie40/05sept1456.jpg

0 section block when they tested with the short.

its not just a case of moaning when i've got total loss of sync..but when the SNR fluctuates heavily i get packetloss.
 
Rocket-Boy said:
Good luck! seems they are very bad at fixing intermittent faults and even worse at actually listening to what the fault symptoms are....
Click to expand...

yip...

example:

i queried the tech about replacement of my 30year old dropdown cable - he sad he would do it if i insist - but he guarantees me - i wont see jack diff - since he recons only at distances between 5-8km would 100m distance reduction help...duh - last time i checked ~6km was max telkom was attempting adsl...

their flowchart is extremely limited i suspect :)
 
@OMN: If you disconnect the line and reconnect does the noise stop for a while?
 
@OMN: Still not convinced that it's a lightning protector - read below. I'm not sure exactly where this would be but there might be one in that white box that you photographed the other day.

bits,

just thought of one more thing.

Has network ever changed out your "protector" (lightning/power surge fuse) in the nid? Sometime these cause trouble and can't really be picked up on the test set except for by a trained eye and even then can easily be missed or not picked up by the test set.

This should be replaced just for good measure. Its on the network side of the nid/dmarc and can be accessed by either tech, network or asi. Technically its the networks techs job to test/replace it, but they're not always alert to this type of problem and since its on the network side of the nid, asi isn't always aware of this issue either. Basically it can be faulty (albeit slightly) and pass dial tone no problem but will mess with the DSL sig.

Please don't ask how I know this! Just ask one of the techs to change it for a new one for grins and giggles, NO ONE is out anything by doing it.

Also, a 3 year old aerial service wire is pretty darn new unless there is damage from storms or critters.

FYI

In the US the telephone companies refer to this kind of surge/lightning protector as a Station Protector.

This is what they look like.
http://www.comm-omni.com/tii/126s.htm
http://www.bourns.com/components.aspx?cmsphid=7631383|7163299|6137660

This explains the types of malfunctions that can occur.
http://telephonyonline.com/mag/telecom_past_time/
 
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update 3 - tech didn't phone back this morning - without LEG A (analogue port (voice)) my line did exactly normal routines.... no improvement - had to phone him up just to get my voice line back up

step 4 - he phoned me 10min later to tell me sorry he doesn't have the equipment or proper exp to work with problem my scale... so he phoned up and "expert" ... <--- to phone me soon

i have removed my gas-arrest red thingy out of the wall socket - but don't know where else in the picture one might be - didn't have any effect.
 
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The red thing is a gas arrestor - these don't usually give many problems. I think that the Station Protector is somewhere on one of the outdoor poles - maybe in that white dropdown box. The Station Protector also contains a gas arrestor as well as another protective element like a backup air gap which could be causing the problem. This is like a capacitor that starts to conduct when the voltage gets too high. It appears that many of them were installed before ADSL was invented and weren't specifically designed to carry high frequency signals consequently they can cause strange noise problems with ADSL although voice signals still work perfectly. It can be easily removed so that you can test the line to see whether or not this is causing the problem. Try to take some pictures if you can when the tech arrives of the insides of the white Telkom boxes on the poles etc. as this may help other people in the future.
 
i'll see what kind of expert they provide - i'll take more phodies anyhow of my setup.

sad story - i've had a visit to a customer today..

poor lady has 384/128 adsl - been having issues for months..

now she is ALOT closer to the exchange than i am - she is 2.7km

however her line stat figures are worrysome - aswell as her line...

sometimes when i pick up her line its CRYSTAL clear - next pickup its so badly flooded with static.

her attenuation is 61.8 - (as far as i know 60 is absolute max to get service - nevermind stable service) - but her SNR shows exactly the same type of behavior as mine..one moment 9 then 21......jumps around alot

i have exluded their alarm system - as i don't have a spare filter to modify for it.

but - she doesn't have the same funny effect of picking up telephone that increases SNR.

maybe i should try and draw up a petition in the entire town to telkom - tell them joints only maintenance doesn't do jack...40year old cables can also get problems.
 
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