volt/amp readings using multimeter on ADSL line

eeeeeeeeeeek
tx power this morning is 1.9 dBm and rx power 8.6 dBm

the inconsistency on the power makes me wonder...

its a problem in the total loop then from exchange to my home.

physical power strength on the line?
card problem in the exchange?
shortage on the line?
birds sitting on the line?
-no wind - no cloud cover - 9'c - so its not cold/heat cycle of copper joints expanding/shrinking.

wish there had been a way to increase the tx power at my side.
 
alright...some sources recon:

Adsl1 runs fixed tx power.

You will find on adsl2+ the figure will be lower generally due to bandwidth and power management facilities depending on the dslam configuration . The tx powers at each end can be varied which can cause the figure to vary .
 
@OMN: Here is the information about an RFI telephone line filter. Basically you need 4 parts - 2 inductors and 2 capacitors. If you have any old blown PC switching supplies lying around you may be able to find two suitable inductors in one of them. You can also buy ready made ones in the US from places like Radio Shack etc. so you may be able to find them here also. I wouldn't spend too much though in case it doesn't help. I'll post more about this later.

http://www.somis.org/T-RFI.html
http://www.somis.org/Phone_f.gif
This filter seems to be one of the best
http://www.ky-filters.com/am.htm

Here is a link to the Radio Shack filter as well as another brand. Read the second comment carefully. Seems like a homemade version works just as well.

http://www.eham.net/reviews/detail/4975
http://www.k-comfilters.com/techbltn.asp

Your Rx and Tx transmit powers seem to be very low but I can't tell you what mine are because my Billion doesn't seem to have this feature. Maybe somebody else can get these figures from their router and post them here.
 
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http://mybroadband.co.za/vb/showpost.php?p=478297&postcount=22

don't know exactly if his problems were the same as mine ..but he found that there had been a power cable in close proximity to his telephone wire.

now the ONLY wires i can think of power related closeby:

-the 220v plug feeding the ups ...
-the 220v plug feeding our aircon - but that has been unplugged for months since we don't use the aircon at all for heating purposes.

pic of my dropdownpole

http://i210.photobucket.com/albums/bb147/jannie40/dropdowntomyhome-middelwire.jpg
 
On that last plot your downstream RCO is *lower* than your upstream one i.e. your ADSL upload speed should be faster than your download one i.e. the small bit of spectrum at the start of the DMT plot is more effective at transporting data than the rest of it!

I wonder how easy it would be to get somebody from Telkom who is competent enough to repair the faults on your telephone line. I think it's very likely that this is the problem with your line - some kind of line fault more than mains interference. Do you know if there are any other ADSL customers connected to your distribution box?

Take a look at this page from Wikipedia about converting dBms to mWs. I think that your downstream and upstream Tx powers are sometimes quite a bit below what they should be.

http://en.wikipedia.org/wiki/DBm
 
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i've got 2 guys i know from the same street box ...

the one stays 5 homes from me - 384 - almost NO issues..

the other one stays back 3 streets - and he can BARELY get 384 -syncs at 288

common factor - we all go thru the same street box...

http://i210.photobucket.com/albums/bb147/jannie40/adsllocations.jpg

i'm at A . friend B at 384 with almost no issues . friend C - terrible stats.

-friend B send me a screenshot of his router info - he had uptime of 4 days with only 2 los of sync in total - BUT - his CRC error count is HIGH (as far as i understand this counter is reset when your router resyncs)

-while friend C had uptime of 7 days but a total los of sync for 46 times.His CRC error counter is VERY LOW - which tells me either his filter setup is not proper. but it worries me that he syncs down to 288

check those aswell

B:

http://i210.photobucket.com/albums/bb147/jannie40/location_B_mr_mur_mullerst_384-1.jpg

C:

http://i210.photobucket.com/albums/bb147/jannie40/location_C_mr_abrie_demist_384-1.jpg

again i've showed these to telkom aswell - they didn't think much of it.
 
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I wonder if you got B's pair from the distribution box whether your ADSL would be better or not.
 
question

on a ups - there is 2 x RJ11 ports. If i were to plug the rj11 directly from my line into that - then the output cable into router - would that:

a) serve as being earthed via ups
b) filter any spikes/surges?
c) aint ups gonna have troubles letting adsl signal thru?
 
@OMN: The telephone filter on a UPS usually incorporates some form of lightning/surge protection. It may even contain an RFI filter. The best is to try it to see if it makes any difference. You can try to run DMT before and after to see if there is any difference.

Regarding the other idea about the A, B and C ADSL customers in your neighbourhood. Is it possible to get DMT plots from their lines? If C's line shows the same behaviour as your line i.e. that large dip between 586 and 656 it seems likely that the problem will be at the distribution box. Does B's line show any problems between 586 and 656? If B is not keen on letting you try out his pair at the distribution box then you may still be able to use C's line to determine your fault. Surely C is not a happy customer either?

If you can convince one of your friends to let you try out their pair from the d/b maybe you don't even need to call Telkom. The idea is just to catch one of the technicians when he is working at the distribution box and ask him if he can quickly help you. You could offer him a small cash incentive. All you need to do is to temporarily connect B's pair through to your phone and get somebody at home to quickly run a DMT plot. This should tell you very easily if the problem is at the distribution box or on the line. If the new DMT plot from your line looks like Bs normal DMT plot then the problem is a faulty pair at the distribution box. If, however, you suddenly see that 586 to 656 dip again then the problem must be on the line leading to your house. I have managed to get a technician to switch my pair before just by catching him at the d/b - took a few minutes at most. You preferably don't want to switch the DSLAM - just the line from Bs house to your house. Maybe he can just install a temporary jumper lead etc. What do you think? Can you first get DMT plots from B and C?

Actually here is an even simpler suggestion. Take a look at the mains power pack on your Netgear router. If it uses uses a 12V supply this means that you should be able to run your router directly off a car battery and connect to it via a laptop. If this is the case just try to catch a technician at the distribution box and ask him to disconnect your home line from the pair at the d/b and connect your router directly to the pair at the d/b using power from the cigarette lighter jack etc. Run DMT and compare the results with what you have already. If there is no change then the problem lies at the d/b otherwise it's on the line to your house. This might be even simpler. How long can you power your router via your UPS with the mains off? This is another option.
 
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thanx for the replies

-well friend at C - says altho his router stat pages look bad - that he is an active DOTA player - and doesn't notice one drop. i doubt :)

-friend B knows what a sync loss is - but he says in the last 6months - things have been stable like never before..

-unfortunately both their routers doesn't support DMT - so i'll consider taking mine to them at some point

so i'll tell telkom tech about this -B- and request a swop - for lines at the streetbox and at the exchange.

there is only one difference then - his cable route stays the same from home -> streetbox - but after a test from my side - we'll be able to tell where the problem lies.

i've now done the UPS "filter" on my rj11 - we shall see...dmt running as we speak.

i'll check how keen the tech is - if i can take my router + notebook with - usually they insist on using their BS little usb blue telkom usb modem with - it can only show u line specs every 5 sec if you refresh - and my plotting program doesn't work with that - so i'll try my best.
 
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That latest plot looks very good. Is that after installing the filter or is it just running well today? Maybe it's just Spring in the air.

I don't think that B will be happy with you if you swap his pair with yours permanently though :-)!
 
negative - line didn't go well

but:

VERY INTERESTING find! ...when my adsl goes into it's mood - and i unplug the telephone filter rj11 + adsl rj11 cable - swop them - then it runs better for a GOOD while until the pattern of being unstable occurs ...must be some kind of resistance...

check the following screenies:

http://i210.photobucket.com/albums/bb147/jannie40/03sept0714dmt_graph.jpg

http://i210.photobucket.com/albums/bb147/jannie40/03sept1338.jpg

http://i210.photobucket.com/albums/bb147/jannie40/03sept1400dmt_graph.jpg

yet again - swopped telephones , swopped filters - have both my router and phones(when plugged in) going thru the ups's rj11 ports (have 2 ups's)

need a degauss button hehe

so having the router just doing a resync on its own doesn't help much - i HAVE to "break" the circuit from my rj11's to the exchange...
 
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@OMN: I think you are getting somewhere now i.e. you know how to get the problem to disappear for a while. It's definitely either some type of intermittent line problem or faulty equipment at the exchange. When you break the circuit it seems to reset. Maybe you could put a switch in one of the lines so that you can break the circuit easily so that you can study it more carefully. At least you now have concrete proof.
 
yip
i've tested it just now

i can pickup the phone and put it down 99999999 times after a fresh reconnect - it won't do 0 to my SNR values...


hmmmmmm

i don't think its a bad line - its power.power.power...
gonna phone up 375375...but trying to explain this - sigh - lol - gonna take some effort - rather just get a tech.
 
@OMN: Just make sure he fixes it this time around. Why do you think it's a power problem?
 
its like a when you have static charge on your clothes and you touch something that earths - then the current/charge between points A and B is equal afterwards..

-that "duration" is now what i think i've stumbled onto.

i recon current from exchange and my endpoint is levelled out when i reconnect everything - but somewhere - something is changing the power.

where - and which direction - i dunno - gonna try get telkom to figure that one out
 
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