volt/amp readings using multimeter on ADSL line

@OMN: There appears to be a noise problem between 586 and 656kHz although after looking at some of the other plots on the DMT website for high downstream attenuations and small SNR margins it is similar except that your noise band is quite a bit bigger. Also it seems that the usual gap between the upstream and downstream tones has been used. I'm not sure exactly what loss of signal means - if there was an intermittent break in your phone line would this apply or would that be loss of power? I hope that you are fluent in German as this program may be able to diagnose your problem. Does the frequency plot vary between when the line is noisy and when it is stable?

Several forumites asked about similar software for Billion routers. The only software that I have been able to find is Zyxmon and Dlmon for Zyxel and D-Link routers respectively. It also seems that Telkom is now supplying the Zyxel IAD P2602 Voip WiFi router free to their self-install customers which is an interesting development. Maybe they are planning on offering a Voip service in the near future otherwise why encourage your customers to find their own independent Voip provider and lose their international business. This Zyxel router can produce a tone plot in the form of a table of numbers which can be easily converted into a bar chart or plotted from Zyxmon.

Maybe somebody else knows more about this Do offer?

http://zyxmon.3daffex.com/downloade.php
http://www.marconisa.co.za/telkom_Zyxel.htm (see the Do logo)
 
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Yotch said:
@OMN: There appears to be a noise problem between 586 and 656kHz although after looking at some of the other plots on the DMT website for high downstream attenuations and small SNR margins it is similar except that your noise band is quite a bit bigger. Also it seems that the usual gap between the upstream and downstream tones has been used. I'm not sure exactly what loss of signal means - if there was an intermittent break in your phone line would this apply or would that be loss of power? I hope that you are fluent in German as this program may be able to diagnose your problem. Does the frequency plot vary between when the line is noisy and when it is stable?

Several forumites asked about similar software for Billion routers. The only software that I have been able to find is Zyxmon and Dlmon for Zyxel and D-Link routers respectively. It also seems that Telkom is now supplying the Zyxel IAD P2602 Voip WiFi router free to their self-install customers which is an interesting development. Maybe they are planning on offering a Voip service in the near future otherwise why encourage your customers to find their own independent Voip provider and lose their international business. This Zyxel router can produce a tone plot in the form of a table of numbers which can be easily converted into a bar chart or plotted from Zyxmon.

Maybe somebody else knows more about this Do offer?

http://zyxmon.3daffex.com/downloade.php
http://www.marconisa.co.za/telkom_Zyxel.htm (see the Do logo)
Click to expand...

well - the line was quiet yesterday morning - and it went bezerk +- 6:30am - had about 168 disconnects yesterday...

but check this - last night it was running smooth again - and in about 90min from now it all starts again

http://i210.photobucket.com/albums/bb147/jannie40/28aug0519.jpg
http://i210.photobucket.com/albums/bb147/jannie40/28aug0515dm.jpg

the Do offer - is Telkom's local broadband offerings
Do1 = 384+1gb
Do2 = 384+2gb
Do3 = 4096+3gb

usually with Do you get either Mega100WR/Mega200VWR/5102G/Marconi Premium Combo Routers. I've not yet seen that Zyxel going with Do..but then again enough router purchasing for myself :) could have bought a ticket to space already :)
 
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@OMN: Keep monitoring the situation - particularly the times when the problem occurs. If the noise is only in a particular range you may be able to filter it using a few passive components.

Take a look at this thread about the new Telkom Zyxel Voip router.
http://mybroadband.co.za/vb/showthread.php?t=85452

Are you able to change the Target SNR from the hidden fifth tab of DMT? I can only see the tab on your plots.

Is Telkom quite sure that they don't have a bridge tap on the line? There is definitely a problem with your plot in the region between 586 and 656kHz. When your line is working correctly the plot still shows two dips in this area. It's possible that there is several hundred metres of unused unterminated extension cable (bridge tap) connected to your phone line that is picking up the interference. The plot should not show those two dips. Does the downstream attenuation still increase when the problem starts with this router? You must just compile enough evidence to show them that your line is not working correctly. They should have equipment that can pinpoint the location of a bridge tap. They should also be able to confirm the increase in line attenuation at 586 and 656kHz.
 
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observation : when my line isn't going thru its rush of errors and its more stable , i've noticed that say my SNR starts to go more flat - say 16-18 - and i would disconnect all the power to the router - let it start up from scratch - it resyncs back to 24-26 (stable)...and keeps flat until my normal morning havock of 6ish...

it just seems as if there is a resistance building up - and by switching power off/on - i break that resistance for the short term.

haven't got to the multimeter yet - but it lets me think i have some sort of power leaking onto my line or something
 
[OUPA]MrNutz;1187771 said:
So i've been having this problem for years of unstable adsl - 384,512,1024..

SNR keeps stable for x min then just disconnects or goes 300% lower than it was originally.

as i said previously - tried TONS of filters - without any extras (just adsl) - 4 routers ect - so its not client side probs.

what kind of volt values should i expect from my line..

gonna get a multimeter today and take a few samples. I do realize that the line is analogue - thus normal fluctuations is to be expected.

if anyone can take a reading for me and post results here with approx distance from exch - that would be great!
Click to expand...

Is your Router connected to a ups? I have found all my client routers having problems espesialy in winter times so i had my local electrical guy come and test our power. Our power tested well under 190 volts, so i hooked up a ups and no more disconections. Thank you eskom!!!
 
@OMN: The bits per tone and SNR per tone are standard ADSL test procedures. Telkom may already have done these tests. The problem is that many of the technicians have these small handheld testers which are very difficult to understand. I'll try to give you a link to one of the manufacturers websites so you can look at a readout to see just how poor the graphics on these testers are. It's quite likely that DMT gives a much better idea of what is going on. Keep on monitoring the situation. Below is a brief explanation on how to identify bridge taps, AC and DC faults and wet sections using the bits per tone and SNR per tone graphs. Unfortunately your router does not seem to be able to provide the bits per tone graph for comparison purposes i.e. the top graph is always blank. Is there a way to get this information from the Netgear? It would appear that you have some type of AC trouble on the loop.

Has Telkom already done these specific ADSL tests? It is not sufficient just to test that the line can handle voice correctly because the problem only arises between 586 and 656kHz i.e. in the AM band. The voice band is only up to 10kHz or so. As you mentioned previously your line handles voice fine so if the technician only tests at low frequencies everything will look perfect. If they use one of those beeping line probes they won't find anything. Do you know if they have done any TDR measurements to look for bridge taps etc.?

Explanation of bits per tone and SNR per tone plots
"If slow service is indicated, technicians can look at the bits per tone measurement. Dips in the bit per tone graph indicate interference. Checking the frequency of the interference often makes it possible to identify its cause. The accompanying chart shows the frequencies associated with common interference sources, such as T1,E1 and HDSL. If the bits per tone are taking a hit and it is determined that noise is not the cause, then the cause could be a DC fault, such as a bridge tap or a wet section. Very low or nonexistent bits per tone in the high frequency band indicate the presence of a long loop. If there is a major dip in the bits-per-tone graph but the noise power-per-tone graph does not show any abnormalities, the most likely troubles are bridged taps or wet sections on the span. Use a loop-troubleshooting tool with a TDR to find and fix these problems. If the bits per tone are low across the whole bandwidth, the cause is most likely DC troubles on the loop, such as shorts or grounds. A major dip in bits per tone indicates AC trouble on the loop. To verify the type of AC trouble, compare the bits per tone to SNR. If the noise influence and bits-per-tone dip occur at the same frequency, the degraded performance is most likely due to a transmission influence. The particular frequency will help identify the source of influence or crosstalk. An example of possible shared frequency zones could be T1 centered at 770 kHz or HDSL at 196 kHz."

Source: http://www.jdsu.com/test_and_measur...ts/whitepaper/ADSL_Technology_White_Paper.pdf

ADSL testers
http://www.jdsu.com/test_and_measur...cuments/datasheet/HST-3000_Copper_and_DSL.pdf

http://www.specialized.net/ecommerce/shop/layout.asp?product_id=350X533

http://www.evaluationengineering.com/archive/articles/1001dsl.htm
 
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Look carefully at your latest SNR per tone plot - the graph looks quite different today than it did yesterday. The peaks have risen while the valley has fallen. Was that graph calculated when the noise was good or bad? Can you pick up any strong AM radio stations or interference in your area at 586, 621 or 656kHz?

It also appears that both your downstream and upstream Tx power is very low in the latest plot. Seems to have changed considerably. Here are some good examples of DMT bits per tone and SNR per tone plots. How does your line compare? Look at those downstream and upstream Tx power values. Today DMT thinks that your line can do 3.8Mbps - yesterday 1.5Mbps (check the RCO value).

http://www.dslreports.com/forum/r17718637-SpeedTouch-516-Tweaking-~start=220

You can also change the Target SNR value on the DSLAM using the Netgear DG834GT from here (just use the DG834GT link) to see if it helps. Maybe you can try it at 9 or 12? This change is not permanent though.

http://www.kitz.co.uk/adsl/frogstats.htm
 
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Kweepster said:
Is your Router connected to a ups? I have found all my client routers having problems espesialy in winter times so i had my local electrical guy come and test our power. Our power tested well under 190 volts, so i hooked up a ups and no more disconections. Thank you eskom!!!
Click to expand...

yip

have 3 different ups's

-mecer 600va
-APC 350Va (good stuff)
-powerline 1000va

all lineinteractive - modified a multiplug so that i can plug 3 devices 2or3pin power devices in...just my router currently in.

did it back from the days of isdn already.
 
Today your line can only handle 800kbps and the dead area between 586 and 656kHz seems to have increased - i.e. there is a slight increase when the noise starts! I'm interested to see how it does this weekend - does the dead area between 586 and 656kHz get smaller or even disappear? Do you have a HiFi or radio that can search this area of the AM band for noise or strong broadcasts?
 
@OMN: I know that you have tried a variety of filters but these all sound like telephone microfilters. Have you actually tried an RFI (radio frequency interference) line filter yet to remove the noise? An RFI filter goes between the router and the telephone line. It's very different from a telephone filter. Many people who live near radio hams have had success using them. You might even be able to get one from Telkom. I'll give you more details if you are interested. You could even make one for around R20 or so if you have a soldering iron.
 
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