volt/amp readings using multimeter on ADSL line

http://i210.photobucket.com/albums/bb147/jannie40/19sept1500.jpg

my browsing speed is now even being impacted on...where i have to go take the phone off the hook and put it back or more simple put - push that button for about 5-10sec for my SNR to regain some health and being able to open websites..otherwise i get page cannot be displayed/gateway timeouts

if i unplug my telephone - the SNR does deteriorate (sp) - then i have no means of "improving" it.

so - running it from a ups does help me not reach a cut-off as easy - but now this is on 512k - wonder what would happen on 1024 - prolly a cutoff - since snr drops about 5-6.

sigh
 
interesting read......

First, line voltage on a typical telephone line is...
-48 volts DC (on hook)
-5.1 Volts DC (talking)
96 volts AC (ringing)

i've just now tried ringing our telephone from a cellphone - SNR doesn't go 1 bit up or down.....
 
Dude, cancel your whole telscum service.
Then re-order the setup, choose closer plan 1 its R15 pm more and it gets you free installation. Then do an ADSL self install.
There does exist the possibility that they will just use what is there already tho in a *new* installation.
 
^^

not possible - i run my business from home.

closer plan 1....uh nope...typo from your side :)

Plan 1 @ R120 per month An affordable option to stay in touch with your loved ones with 30 FREE local minutes for calls during Standard time

i've got closer 5 already.

and for the part of that they might use the infrastructure currently in place - 200% correct.

....made a few calls yesterday looking for a specialist....wait and see what turns up.

normal techs just aint capable to understand these problems...nevermind solve.
 
Rocket-Boy, what are you doing posting in here? I thought you didnt know how to abj00ze a VAmeter. *duck & cover*
 
Voicy said:
Rocket-Boy, what are you doing posting in here? I thought you didnt know how to abj00ze a VAmeter. *duck & cover*
Click to expand...

Dude online tonight im going to choose the other team so i can shoot you in the face!!

I have no idea how to use a VAmeter but i was just being supportive...
 
[OUPA]MrNutz;1235014 said:
interesting read......

First, line voltage on a typical telephone line is...
-48 volts DC (on hook)
-5.1 Volts DC (talking)
96 volts AC (ringing)

i've just now tried ringing our telephone from a cellphone - SNR doesn't go 1 bit up or down.....
Click to expand...

ok got multimeter in hand

52 volts DC on hook
8 volts DC off hook
varying DC when ringing max 62 volts DC
phone plugged out - via filter only 52 volts DC

i'll measure the dropdown wire itself and report back
 
There are variations between the phone voltages that are used in different areas etc. so unless you know what they are supposed to be in your street the actual values aren't that helpful. However, any variation in these DC values over time would probably indicate a line fault. If you leave the multimeter connected do the on hook and off hook voltages stay absolutely constant over time i.e. does the needle show any slight movement? It's probably best to take all measurements with the router disconnected but the phone connected as it draws a small current from the line otherwise the voltages may rise slightly.

The most important thing is whether or not the on hook and off hook DC voltages stay constant particularly after playing around with the on/off hook switch on the phone. If they vary from your values of 52V (on-hook) and 8V (off-hook) then this should indicate some type of problem. Do the DC voltages stay constant during the day when the noise problems usually occur?

You will need to put the multimeter onto an AC range to measure the ringing voltage. I think there is also a DC component in the ringing voltage so this may be a bit difficult to measure accurately. You could try to measure it on the AC range by connecting a small capacitor (i.e. 10-100nF etc.) in series with one of the wires to remove the DC component otherwise the DC component may cause the meter to give a false reading. This isn't really such a useful measurement in any case as your phone does appear to ring. The DC on/off hook voltages should be much more useful.

Can you test for a small voltage between either of the phone wires and the telephone pole ground - particularly when your line is behaving badly? Some kind of earth leakage would definitely indicate a fault on the pole.
 
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purchased a digital multimeter..

the most variation i could see had been about .3 DC volts during the day - but not in a short time lap diff....its like its weaker in the early hours 51.9 and then gets "more" to about 52.2 - 52.3 in the day.

same observation (.3) for off the hook.other than that they stay "constant" ...not like my graphs :)

very pissed off - didn't post on hellopeter.com - since i see about 15% of people get replies within only a month after posting.

so we decided: we are going to apply for a TOTAL NEW telephone line.

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

try and organize the "blue" line in the above picture.

then swop our adsl over from old line to the new line...thus skipping the 138m line.

i SMS'ed the tech on wed...asked him what is taking so long - he said no - he gave the problem over to the specialist - but specialist wasn't responding to him or myself yet...so in total - i tried 3 times now to get specialist here. no-go.

have also tried a local earth leak test - the readings stay constant - no fluctuation.

like i said in the other forum posting - if proper optic planning to the distribution box had been used from the beginning - would prolly never have had this problem...but thats hellkom and having a monopoly.

out.
 
@OMN: This is probably your best option after all the trouble that you have been having.

Try to read this article very carefully before doing the new installation so that you understand very well what the requirements are for a good ADSL line. You should try to make sure that the new line is well balanced (i.e. the DC resistance of both wires is closely matched), no bridge taps are present (i.e. preferably no dips in the DMT plot), a very high insulation resistance between both wires and ground, no foreign AC voltage present on the line etc. Read the bit about the correct DC voltages and the DC voltages between the tip and ring and ground when the cable is wet etc. I really hope that they manage to do it properly this time around!

http://www.teracomm.com/appnotes/whitepapers/Copper Testing for ADSL & ADSL2+.pdf
 
cable contractor pitched up today - they "CLAIM" that the underground cable between my distribution box and 1st air cable entry point is damaged... they going to try spare cables..

now whats the diff between a spare cable and diverting a line (if only 1 path is available in total)
 
Let's hope they fix it this time. Any idea why they only noticed the problem now after all this time? Your latest bits per tone plot looks very bad. It seems that your router is now unable to use a large section of the low frequency downstream spectrum which is very strange.

Just copy this line of data and paste it into the first cell of an Excel file.

0 0 0 0 0 0 0 0 2 4 5 5 6 6 6 7 7 6 6 6 6 6 6 6 5 5 5 5 5 3 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 2 3 2 2 2 2 2 2 2 2 2 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 2 2 3 2 2 3 3 3 4 3 3 5 6 6 6 6 6 5 5 6 6 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 4 5 5 4 4 4 4 4 4 4 4 4 4 4 3 3 0 0 2 3 3 3 3 2 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 2 2 2 2 2 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Under the Excel Data menu there is an option Text to Columns. Select that and choose delimited. Then click Next and tick Space as the delimiter. Then click Finish. Select all the cells containing data in the first row. On the toolbar click the chart wizard and select the column chart type. Choose the first subtype and plot the graph. If you have done everything correctly you should see a zero in row 65 i.e. at tone 64 - this is the pilot (and usually tones 63 and 65 should be non-zero). In your case there is a whole region of spectrum around tone 64 that can't be used so it's hard to believe that the pilot can still operate reliably on your line.

Some background info on the pilot tone
http://www.patentstorm.us/patents/6985548-description.html
 
yeah - that was done with the 5102G....very bad resync speed - very weak under poor line health conditions.netgear ftw!

the cable contractor had apparently done his work this afternoon - but sofar - i'm not impressed - they didn't bother to report back to me - or neither did anyone from telkom phone me up to get back to me..as i asked nicely for them to phone me..

anyhow - have a specialist from Pretoria maybe getting over here soon - he has been assigned to test segments and also install new local lead pair.
 
This is starting to sound like a fulltime occupation! So many visits, phone calls, appointments, experts, technicians, missed appointments, calls not returned etc.

It would appear that the Broadcom based Netgear is much better on noisy lines than anything else that is available on the SA market.

These two commands apparently work on a USR Broadcom based router from the CLI? Any chance they work on your DG834GT?
adsl info --SNR
adsl info --Bits

Maybe this helps
http://bbs.adslguide.org.uk/showthr...&Number=2363243&page=3&view=expanded&sb=5&o=0

Here is some information about how to get the DG834GT to show the bits per tone plot correctly in DMT. You better investigate this thoroughly first to avoid bricking your router!

qwerty12,
Thanks for the information.

On the Netgears official website, witch DG834GT firmware does work without the need for a mod? and where do you get adslctl2 download link from?

Kind regards
Sylver123

Hi.

http://kbserver.netgear.com/release_notes/D102796.asp - is the latest and the one I am using. But because of the newer kernel ; it is the only firmware where adslctl2 will run.

Although I do recommend the UberGT mod as it seems a bit more stable to me and it has added features. It's just a mod of the firmware, not a completely new firmware. It still has the original features and web interface but with a few more options.

If you do want to upgrade ; do it through ethernet and make sure you download http://kbserver.netgear.com/release_notes/d102417.asp as well (it works fine on DG834GT but you need xp to run it)

I've pm'ed you the link anyway to the adslctl2.

Best Regards,
qwerty12


DMT DG834GT forum
http://forum.mhilfe.de/viewtopic.php?t=2080&postdays=0&postorder=asc&start=180

More on UberGT
http://dragonslight.altervista.org/ubergt/index.html
http://www.dslzoneuk.net/forum/viewtopic.php?f=23&t=3409&st=0&sk=t&sd=a
 
flashed my DG834GT with latest firmware.

just before 8 this morning something broke somewhere - but nothing at my side - its a normal 678 exchange/ESR problem...

the firmware enabled me to see all 3 DMT tabs.

check : http://i210.photobucket.com/albums/bb147/jannie40/4oct0833dmt.jpg

the empty lines might be due to the fact that the ADSL upstream is "not connected" - have sync however

line is not behaving very well this morning - 1024 profile is jumping around - currently synched at 640down384up.

i'll post a complete DMT when we have no more 678 in progress

viva vodacom hsdpa :)
 
MrNutz & Yotch
I have been following this thread and thanks for all the info contributed. Hope your line gets sorted out soon.
I decided to try and get similar info out of my router. As I don't have spare cash lying around to get a Netgear, I researched my router a bit to get some info.
I have a 4 port Edimax AR7084A ADSL2+ router. The router interface (web) looks identical to the Billion 5200 series. The chipset used in the Edimax AR7048A and the Billion 5200/S is the Trenchip TC3162. Certain models of Zyxel modems and the Billion 7300G modems/routers also use this chipset.

I successfully able to generate bits per tone plots using the Zymon v0.62b software (http://zyxmon.3daffex.com/downloade.php - link given earlier by Yotch) for the Edimax router. This should work for routers/modems using the Trendchip TC3162 chipset. The DMT tool will only work if a router CLI supports the "adslctl" command.

I also found another site with software that was compatible with the Edimax router. The tool is called OrbMT and can be downloaded from: http://blog.orbmu2k.de/tools/orbmt-modem-tool-sidebar-gadget/
The software is in German but is pretty easy to figure out. Click on "Einstellungen" to get to options. Then select modem type as "Zyxel P-653HWI-17" for Edimax/Trasnchip TC3162 type routers. passwords etc for router can be filled in. Click on "Status" tab and then "Aktualisieren" to get the router and line stats.
I am sure other formites could check if it compatible with other routers.

Another site is also http://www.webtemp.org/index.php?page=sm50b&lang=en
I have not checked the tool yet.
 
hey man - youre welcome - hope all this info has helped alot of people..

i've got a request - yotch you are welcome as well - can you guys maybe plot your SNR graphs/dmt like info - i'd really like to see what your lines are doing..

anyone outside - have a bash - the links are in this thread - post - lets see who's copper can behave the best and worst :)
 
@tjandies: Many thanks for your suggestions and advice. I have a Billion 7300G but I have not been able to get Zyxmon to work. I hope that one of the other Billion 7300G owners will also give Zyxmon a try and let us know. I haven't tried it using Windows XP - this may be the problem. Do you perhaps know what chipset is being used in Telkom's Zyxel IAD P2602?

I have found that you can obtain the bits per tone matrix for several of the Billion routers/modems with the following commands. This also apparently works with the Telkom 5102G (thanks OMN). Maybe you can also try this out on your router.
telnet 192.168.1.254 (replace with your router IP address)
username: XXXX (type in username)
password: XXXX (type in password)
wan adsl linedataf1 OR wan adsl linedata far (works with Telkom 5102G).

Now just copy and paste the tone data into notepad. You only need the lines from tone 0-31: onwards. Using the editor just remove all the text including the : i.e. tone 0-31: tone 32-63: etc. so that you just have a matrix of numbers i.e 16 columns with 8 rows. In notepad just join row 2 onto the end of row 1. Repeat until you have joined all the rows in order into one long row. Make sure that you don't put any of the rows in the wrong order i.e. the single row must look like this row1 row2 row3 row4 row5 row6 row7 row8. Now put spaces between all of the pairs i.e. 00 00 00 00 24 -> 0 0 0 0 0 0 0 0 2 4 etc.

Once you have done that Open Excel. Using notepad copy the whole row and paste it into a single cell in Excel. Under the Data menu there is a menu Text to Columns. Select that and choose delimited. Then click Next and tick Space as the delimiter. Then click Finish. Select all the cells containing data in the first row. On the toolbar click the chart wizard and select the column chart type. Choose the first subtype and plot the graph. If everything has been entered correctly there should be a zero in row 65 i.e. at tone 64 - this is the pilot. This is a very rough method to view the bits per tone and doesn't provide any of the additional features that DMT does.

Here is a rough bits per tone plot for my 384K line.
http://i217.photobucket.com/albums/cc189/Hinapina/7300_384K_24188_image001.gif

I have not been able to get any SNR per tone data out of the 7300G so far. It would seem that this might be possible using SNMP (Simple Network Management Protocol). Here are some programs which might be useful although I haven't had any luck with them. Let us know if you have any success.

SNMP test software
http://www.programurl.com/snmptest.htm
Free SNMP
http://www.nsauditor.com/network_tools/snmp_mib_browser.html
BPSNMP Utility
http://www.bpsoftware.com/products/BPSNMPUtil/
The software mentioned in this link appears to be much larger and more complex
http://www.geekball.net/linksys/LinksysSNMP.html

Technical ADSL specifications (look for terms like adslAtucDMTBinSNR, adslAturDMTBinSNR, adslAtucDMTBinAtn, adslAturDMTBinAtn, adslAtucDMTBinBits, adslAturDMTBinBits etc).
http://www.dslforum.org/aboutdsl/TR-024.doc
 
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