volt/amp readings using multimeter on ADSL line

Yotch said:
@OMN: Latest doesn't sound too good but maybe you'll be lucky. Yes, 384K is a lot more tolerant than 4Meg but I think that in your case you may even have problems with that. Any idea of the cost of a new 2.4km pair? If you ever see a technician working at the distribution box I would ask him privately to try to find you a better pair to the exchange in the meantime now that you know where the problem is as Telkom may keep stalling you for months. If you ask Telkom to do this now they will probably just assume that they don't need to replace the cable anymore. Unfortunately any viable alternative to Telkom still seems a long way off.
Click to expand...

yip - the capetonian sorta suggested - lets go to 384 - i told him - sir this happens 384/512/1024 - whichever one u like.

i spoke to a senior person in Pretoria yesterday - who was really of opinion of replacing with optics...

and then came this unfriendly character from Captetown -saying optics is not an option due to local demand and cost.

i don't have a problem in not receiving optics...a brand new 2400m set of copper is 100% - i've seen a local 4096 profile on 2.6km with NO issues.

its a situation now if me getting angry with other senior people(who are keeping themselves not-so-well-informed)phoning me and playing snakes and ladders - which seems to keep taking me back to the beginning...

ANYHOW - those that i have got good ties with in this investigation - I am going to organize something today - that ONLY with my signature - can this special investigation be closed - because that is what i am sensing: they KNOW they need to rush/hush/get their act together "yesterday" already - and their internal SLA with special investigations are counting against them.

their managers are going to be RED hot by Friday - come monday , all hell brakes loose on them :)

so i'm gonna play "hardgegat" until they can fix this time - or provide me an alternative....hmmm - lets see - 512 wimax , ISDN30 with special dialup numbers (if it exists).

i'll keep this thread updated. its a shame in this country proper communication is such a BIG problem.
 
Good News

ok we are 99% home!

they somehow managed to get an OPTIMAL "clean" pair from the exchange to the distribution box.

so this had been 1st big improvement from their side.

yesterday tech with his advanced testing equipment came - spend the entire day here - took the day off - went with him EACH step..

located 3 problems.

A-no working grounding!!! on my dropdown wire cable pole
B-"balance" problem between house and dropdown cable
C-"balance" problem between dropdown cable pole and pole running on the side of the house

so we created a new temp.ground - long screwdriver and piece of cable into the ground - tests showed MUCH better results!

also

he then decided to "skip" the connector bloks inside the boxes and join the lines directly - it worked!

now - cable infrastructure manager had a 3way conference call with us and we decided the last 2 segments need replacement or skip it all together - so its now certain: the new entry cable is gonna do the job 3 poles down from me!

AMEN ! - had the feeling for a WHILE that from there it would be solved..but they had to confirm it with testing equipment.

all HAIL sunrise sunset mmt and 3m dynatel 965P :)

check this!!!

RCO 18% 5664kbps :)
http://i210.photobucket.com/albums/bb147/jannie40/25oct0518.jpg
 
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Good to see that things are finally looking up. It's quite ridiculous that they have only sorted out your problems after several *years* worth of complaining. It sounds as though your telephone line was never installed properly to begin with if there was no proper grounding stake.

How exactly is the grounding connected? Does each pole have its own stake in the ground and then each of the pole grounds is connected to its neighbouring pole ground at the top of the pole and finally to the ground connection from the exchange? You should also ask whether or not it is recommended to connect the ground from the dropdown cable to your house ground or maybe you have done this already. The Americans seem to do this but their electricity supply system is a bit different from ours.

What exactly is inside those little boxes on top of the poles? Do they contain a station protector/surge protector or just some type of connector block? If you have any lightning problems in your area I would also enquire about whether they can give you a new station protector as the surge technology in these devices seems to have improved a lot over the last 10 years or so - that's if they even use them! They only cost a few dollars and could save your router and phones. I would also ask about sealing the box and rubber boots with a small amount of silicon sealant to prevent any water from getting inside during heavy rains once they have finished the repairs. In one of your pictures of your dropdown box the boot seems to be missing so I have to wonder what happens in there when it rains!

Regarding the plot - it seems that your line now has so much spare capacity that it is no longer using all of the bins. It will be interesting to see what happens if you increase the speed to 4Mbits/s. Your downstream noise margin now seems to be extremely stable which should increase the top speed that you will now be able to achieve. Anything above 5Mbps for your distance from the exchange I would think is excellent.

If I am reading the tables on the right correctly I see that there are still quite a few CRC errors but this may be normal for your distance from the exchange - that's if the data only includes the period that the line has been stable and not the errors from before etc. How many CRC, ES, LOF, LOS errors are you now getting per hour?
 
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Well - its now almost 48hours later since the last work done - and i have not had ONE disconnect ...not ONE - i cannot start to explain how weird it feels - playing online games (bf2) and not to worry about when it is gonna disconnect!

Such a pleasure!

Yeah - upgrading now from 1024 to 4096 is tempting - but my SNR of 19-21 makes me rather go for 3072 instead of 4meg.

About the grounding - i was shocked to see this - my pole is the last in the sequence - has got a HUGE earth pen at a 45' angle into the ground - and it then goes on top of the cable towards the next to carry/forward the earth to the next in the chain.

http://i210.photobucket.com/albums/bb147/jannie40/dropdowntomyhome-middelwire-1.jpg

Like i said in the previous post - the earth had been "detected" "dead" in the ground...can lightning zap that rod really dead? - because i saw with my OWN eyes how we manually used a flatscrewdriver into the ground with a 4meter thin (telephone) copper cable - and test result had been TONS better...

So the grounding if "forwarded" from the 1st pole (tested ok) - to the last - where it also has a 45' earth pen (my side - didn't test OK).

Well - whats inside those boxes - 1) the thin colour codec cables that are connected in their seperate pairs by a scotch lock.

http://www.pyrotechnic.ch/Images/Scotch Lock 1.JPG

2) A black connector strip

http://www.chinapans.com/images/20paird.jpg

Sorry for the blurred picture - but its almost like this - except not the things on the left hand side.

As far as the water condition goes inside each box - the previous night we had a HUGE HUGE storm - so it had been an excellent time to check - and i can gladly confirm - not ONE box had ANY water inside - as the box is L shaped - and the cover is just the opposite match with a bit more to let the water drip away from the box.

Regarding the plots :

Not once did it drop below 17 SNR for the last 1.5 days and neither has it gone above 22 ... yeah i agree - aka DMT there are a few errors left - but like i said the situation is not yet 100% - but almost - they are gonna skip two faulty segments of cable which should give me optimal results..i'm doing a 60min DMT check - gonna post the results a little later.

Also being 3.59km from exchange with line attenuation +-52 - i'd suppose CRC free connection might be out of the question.

Anyhow - things are really looking up.

Tools they used:

http://www.phoenixdatacom.com/sunrisexdsl.html
http://maillist.southernhydraulic.com/9/ad-965-dsp-3M-dynatel-used-works-excellent-/
http://www.sunrisetelecom.com/mtt/ADSL.shtml
 
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The best test would be to try to increase the speed to 3Mbps! I hope those CRC errors don't come back to bite you. How stable is your upstream noise margin?

Is is possible that the grounding stake is very rusted or corroded under the soil? Is the stake made of mild steel, copper or maybe galvanised or plated mild steel? Lightning shouldn't damage it. If the soil is wet from the recent rains there shouldn't be a conduction problem unless the ground stake is badly corroded (completely black and corroded) or there is a bad connection in the wiring on the pole.

Here are some results from DMT on a good ADSL line. Apparently ADSL1 can reach speeds of 12Mbps on such lines. Even DMT seems a bit surprised trying to fit in all of those bins.
http://en.wikipedia.org/wiki/Image:Gdmt20071005_0112.png
 
gonna increase to 2meg,3meg and 4meg - and do 12-24 hour tests to see what is stable/acceptable.

the grounding stake is a 2meter pen in length - the composition of it - i totally do not know - looks like a iron rod?

well - as you know the problem occured during the winter,spring and summer - dry spells and and within extreme wet.

as per that DMT - yeah well - i have no idea why they have such a lot of values and me so little :)

i'm upping to 3072 tomorrow - i'll let the thread know what the situation is before i get greedy and go to 4096

thx Yotch!
 
Speed has been upped to 3072 - aaaah - very nice LUKE!

anyhow -

SNR between 12.9 and 13.1 down from 20-21 with 1024
Attenuation down - 52 - exactly as with 1024

SNR up - 12.0 - had been 12.5 on 1024
Attenuation up - 31.5 - same as 1024

line steady at the moment - no one drop yet on 3072.
 
Any idea how cisco 800 rate with noise. Looking after 80 adsl sites with 1min dropouts everyday. Would a Billion router be better
 
@haydn23: That might be a firmware issue with the Cisco. Take a look at the link below for more information. Maybe you should do a test with a standard consumer grade router first and compare your downstream and upstream SNR margin figures with those that the Cisco is reporting to make sure that your line is noisy and that it's not a firmware problem with the Cisco. Some routers do handle noisy lines better than others.

The Cisco 800 series apparently uses the ST-Micro DynaMiTe (formerly Alcatel Micro Electronics) ADSL Chipset which is supposed to perform well on noisy lines but the first link below might suggest otherwise. If you can provide more information about your D/U SNR margins somebody might be able to help further. Billion routers in general apparently do not perform as well on marginal lines as some of the other brands like the Thomson SpeedTouch series or the Netgear DG834GT (Broadcom chipset).

http://www.mcse.ms/message2309416.html
http://forum.exetel.com.au/viewtopic.php?p=182512&sid=3f45976a1d253dd4b7ede1d06750c84e
 
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Hey guys, thanks for the thread, need to know whether problems after my upgrade are due to bad SNR etc.

I had a 512 for years now and almost never had a problem. Then I upgraded to a 1Mb+ a month ago and everything has just gone pear-shaped since then, with the router (a D-Link DSL-504T router) dropping the connection randomly (sometimes for hours on end.) I had the technicians out 2 weeks ago and they fixed something at the exchange, which seemed to solve the problem, but as with all my previous Telkom experiences, it turned out the fix was half-arsed as always, as the line started dropping its connection 2 days after they fixed it, (it only dropped once while it was "working") although at a slower rate than before.

My stats are:

ADSL Firmware Version: 4.03.03.00 - 3.02.00.03 - 3.02.06.00 Annex A - 01.07.02 - 0.49

ADSL Software Version: V2.00B01T01.EU.20050930
Line State Connected
Modulation Multi-mode
Annex Mode ANNEX_A
Max Tx Power -38 dBm/Hz

Item Downstream Upstream Unit
SNR Margin 5 12 dB
Line Attenuation 54 27 dB
Data Rate 3552 384 kbps

these rates are about average, after refreshing the ADSL status every 30 secons for about 15 minutes

Do any of you have a suggestion as to what I should do, any help would be greatly appreciated, I need my WOW fix and my stock-trackers are useless with the constant drops
 
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Item Downstream Upstream Unit
SNR Margin 5 12 dB
Line Attenuation 54 27 dB
Data Rate 3552 384 kbps


-tells me that you are very far away from the exchange - about 4km

-data rate at 3552 : i would phone telkom and ask for a 2048 profile - since the upgrade to 1 meg pushes you automatically up to 4meg - and the per 32kb stable detection side of the dslam doesn't work properly. That should solve your problems. Worst case - down it more to 1024
 
Thanx a million for the info, will try to phone them this weekend, hopefully it works, will post when something has happened
 
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@Maloom: First try to find a speed at which your line is stable as mentioned above.

If you really want to get ~3Mbps+ speeds you may have better luck with a router which is more suited to a marginal noisy line. The best option would be to try to borrow a router from somebody and test it out. The Netgear DG834G or DG834GT are both supposed to perform quite well on noisy lines. You could try whatever other models you can borrow though. If you find that another brand works reliably then you could either buy the same router or something similar. Unfortunately good quality routers are quite expensive in SA.

You can buy high quality refurbished routers in the UK for around 15 Pounds although you would have to check on postage and bank charges to determine whether this is a worthwhile option or not. Take a look at these links if you are interested. The Thomson SpeedTouch as well as the 2Wire brand are both considered to be very good on noisy lines. Do a search on Google for SpeedTouch and noisy lines etc. if you want more information. If you choose a Broadcom based router (SpeedTouch 580, 585 or Netgear DG834GT etc.) then you can use diagnostic software like DMT to vary parameters like the D/U Tx powers etc. which may also improve stability etc.
http://www.dsldepot.co.uk/index.asp?idprodtype=3
http://stores.ebay.co.uk/DIGIDAVE-BROADBAND-STORE_W0QQssPageNameZstrkQ3amefsQ3amesstQQtZkm
 
Thanx Yotch, have a friend with the netgear, will try to borrow it this weekend and see whether there is an imrovement
 
maloom said:
Thanx Yotch, have a friend with the netgear, will try to borrow it this weekend and see whether there is an imrovement
Click to expand...

Netgear834GT is a VERY VERY VERY nice router!

Its not the most advanced in terms of features , but having it working nicely with DSLAMS + diagnostic software that works with it surely helps A TON more than regular telkom routers.
 
Hey, guys, just like to report back, the netgear works a lot better, but still some drops. Also found out the exchange is less than 2km from my house, so phoned telkom and now waiting for their technicians
 
@maloom: Where did you get the information about the distance to the exchange from?
You need to know the distance that the cable follows from your house to the exchange - this is usually much longer than the shortest route on a map for example. A telephone line can't just cut across roads etc. If your neighbour though has ADSL and his router is reporting a much lower attenuation than yours then you probably do have a line fault.

From the sound of things you should be able to get a stable connection if you reduce your line speed as OMN suggested in his post. I would try this first before looking into line faults. If you are still having dropout problems at 1 or 2Mbps then you definitely need to investigate further.

If the attenuation figures (54dB) that you posted are correct it's very unlikely that you will be able to get 4Mbps speeds as there is a limitation on the maximum speed for that D/S attenuation of ~3917kbps for ADSL1. Typically this figure can vary by 10 or even 20 percent in practice. Can you hear any faint crackling noises or notice anything else unusual to suggest a line fault? You did mention that the 512Kbps service was working perfectly before which would seem to suggest that your line may be operating correctly.
 
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Alrighty..

Alot has been done - line has been moved - and i'm over the moon with my stability.

The average SNR for 2048 for my location was about 14.5.

3072 had been 12.9-13.1 SNR.

Today they (telkom) decided to bump me to 4096 - currently at 11.9 SNR.

I'll measure the fluctuations on 4meg - and see if i can live with it - otherwise - 2meg is fine for me :)
 
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