LOS errors

I am facing a problem of excessive desyncs, and, have cornered down the issue to "LOS errors", they increase above 200 and the modem desyncs (sometimes my DS margin goes into a figure of something like 2484905903, sometimes they fluctuate too much like decrease/increase of 10 figures; however I find the main issue with LOS errors). Here are my stats:

Modem Status

US Margin 19

DS Margin 16

Trained Modulation ADSL_G.dmt

LOS Errors 177

DS Line Attenuation 11

US Line Attenuation 6

Peak Cell Rate 1509 cells per sec

CRC Rx Fast 0

CRC Tx Fast 0

CRC Rx Interleaved 260

CRC Tx Interleaved 160

Path Mode Interleaved

DSL Statistics

Near End F4 Loop Back Count 0

Near End F5 Loop Back Count 0

My telephone line is crystal clear. The line from DP to my modem is direct (via a filter) and the main line is very new, almost 16 months old, only.

I have tried almost everything but nothing helps e.g.

1- Removing the filter and plugging the line directly into the modem. (Somehow all PTCL -Einsteins- suggest that)

2- I have two modems, AZTECH and SHIRO - interchanging them doesn't resolve the issue. (One thing I noted that for last few days, my Aztech modem can not connect on ADSL2+)

3- Tried two filters, doesn't help.

4- Tried to use almost every kind of modulation. ADSL.G.dmt was stable a month ago, but now it is not.

5- RESTARTING THE MODEM, will make it work for 4-5 minutes; and then to make the internet work again, in 9 out of 10 cases, I need to restart the modem.

6- Put everything on voltage stabilizer.

My exchange staff is VERY lazy. In any case, they are not willing to change my modem or change the port or, anything. The line, again, is very clear (and I don't find anything to pay four digits figure to get my pair changed, cabinet jumper changed or the jumper at DP rehashed or maybe a new line).

It's beyond my comprehension on how to resolve this issue. Any assistance will be of great value.

PS: I am from Karachi.

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Dear Qasim (firecruz),

Hope you are doing well.

I would appreciate a lot if you could provide your assistance on a PTCL DSL issue I am facing. The details are on http://www.wiredpakistan.com/forums/viewtopic.php?id=11906 .

Thanks in advance.

Sincerely,

Owais

[/quote]

ok owais with the stats as show above uve got no such probs with line(with respect to stats indicated) otherwise if that varies in real so much! it can be some!..here u can try two things…ask the exch people that u want a zte wala modem! and if that doesnt works out…bro try to check your self you in home cables…its quite possible that your in house wiring is causing such thing if aint coming dirtly to the room at short distance!

Thanks a lot. I do not have concealed wiring, and, the line is coming directly. However, Let me change the cables coming in and out of filter, will purchase new pieces in evening.

Few days ago, they were not willing to change the modem (because according to them, it was *somehow* syncing - and if a modem doesn't sync at all then and only then they change it). Will try to argue soon (or maybe bribe b/c thats the only thing they listen to), or, will try to lend the modem from a friend.

where is your filter placed? i mean i hope its not out side....and what are u changing!.... as said the really change it if modem doesnt connects at all! so u might borow a modem from frnd...and then may try yours on his phone line!...will make this bit clear!

It's inside my room. The distance of main line from filter will be like half meter.

Ok, then, let me try swapping the modems first.

Yes, the modems are connecting but the sync is *very* unstable. But, once I restart the modems, the stats become good again, it works for few minutes and then dead.

I was referring to change the telephone cables (small wires) coming in and out the three ports of filter.

After 15 minutes of shutting down the SHIRO modem and restarting it, the stats are:

Connection Status Connected

Us Rate (Kbps) 639

Ds Rate (Kbps) 6139

US Margin 21

DS Margin 31

Trained Modulation ADSL_2plus

LOS Errors 0

DS Line Attenuation 15

US Line Attenuation 6

Peak Cell Rate 1507 cells per sec

CRC Rx Fast 0

CRC Tx Fast 0

CRC Rx Interleaved 0

CRC Tx Interleaved 3

Path Mode Interleaved

EDIT: After 5mins of perfect operation:

Connection Status Connected

Us Rate (Kbps) 428

Ds Rate (Kbps) 6139

US Margin 6

DS Margin 8

Trained Modulation ADSL_G.dmt.bis

LOS Errors 0

DS Line Attenuation 21

US Line Attenuation 38

Peak Cell Rate 1009 cells per sec

CRC Rx Fast 0

CRC Tx Fast 0

CRC Rx Interleaved 29

CRC Tx Interleaved 25

Path Mode Interleaved

DSL Statistics

Near End F4 Loop Back Count 0

Near End F5 Loop Back Count 0

Now when I go to exchange, they check it on their system (of course it will work on their perfect lines). All they say is that the modem is perfect and they won't change it.

The only explanation I have for this anomaly is maybe both of my modems are cooking to hell heat. :S

Swapped modems.

a- ZTE is working perfect on my line for the last 30-40 minutes.

b- SHIRO is working perfect on my friend's line.

It's going be very very difficult to explain to the lazy people @ exchange to give me a ZTE (and I am not sure if 100-200 'ka note' will convince them or not). firecruz can you tell me some technical lingo to tell them?

Anyways, if nothing happens in say a week or two, I should buy this: LinkSys WRT-120N

http://homesupport.cisco.com/en-us/wireless/lbc/WRT120N

I think LinkSys is the best and should resolve these SICK modem issues. By the way, my modem stays on 24/7 (in normal room temps, no AC).

Hi bro, i know it a lot painful when ur modem keeps on desyncing. Till last week i was also facing this very problem but the issue was in the local pairs which my line man changed and since than it is working like a charm. Let me suggest you a few things. Firstly go and complain to PTA maybe through their website or their phone number. If this doesn't works than personally contact your lineman and do a little bit of buttering usually it helps a lot. How ever if u cant get hold of him than just simply call 1218 and literally shout on them in decent language i mean just keep on saying that please do disconnect my phone and always use English as a medium as it imposes a lot of BHARAM on these PTCL CSRs. I got my issue resolved by calling 1218 and literally my issue got resolved same day and since than i have received at least 10 to 15 calls from different PTCL offices including Islamabad and general head office etc etc. Even the broadband guy turned up today at my door asking if i had complaint about the service which i had not so he left. If nothing works simply go to ur exchange's broadband division and tell them ur problem they will surely get it sorted down and MOST IMPORTANTLY DON'T KEEP ON ASKING FOR MODEM EXCHANGE. as it is not ur modem issue but weak pair issue. Hope this helps you

@basitnamdar: I appreciate your detailed response. I have used the PTA card successfully against PTCL (when I was not upgraded) and Worldcall. I use it as a last resort, only. In any case, I have complained on PTCL as well as PTA (did that at around 2pm today).

At the moment, with my cousin's ZTE modem (and change of small telephone cables coming out the DSL filter), Internet is working perfectly. Therefore, I won't be requesting a pair change and would demand a modem change only.

The phone line is absolutely perfect on ZTE at least , plus, I am on fiber optic. (Noise Margin 31.7 Line Attenuation 19.5).

@owais

your case is bit twitchy!...please confirm if that ZTE is still constant!.... actually sometimes ONU's do a SELT/DELT test to make line corrections! and as ONUs mostly are of ZTE so they can test only the ZTE models! (freaking limitation) anyways!

Just confirm your modem thing with your cousin's ZTE! and if it goes fine than you know what to do!....btw u have onu line and even in case of ur line prob it will only be the secondary cable issue (cabinet to pole)

and its like half meter and its in room! amazing! btw those small cables change wont help much!

@firecruz: I was in the exchange today (freaking 3 hours) and just returned. The guy there said exactly the same thing that a "pair change" won't do much on ONU, you should get your line corrected from the DP.

Last night, ZTE worked perfect for 10+ hours except for the 5-10mins, when there was "some weak" noise (not baghdad bomb line, just weak noise) in the line (which vanished itself after 5minutes).

The exchange guys managed to give me "ZXDSL 831 CII" [edit: oops just realized this is ZTE as well, but with 4 ports :P]... let's see how it works.

I don't think I can manage to get my line pair changed (they are not agreeing to that).. but I shall try to convince a lineman to change the jumper at my DP. My DP (altough just a year or 1.5 yrs old) is very badly managed, it's cover is removed and open wires hanging here and there.

The SNR sometimes change very wildy (the max I get is 31 SNR, on 6mbps line and even on ZYDSL i noticed +/- 8-10 drop in the beginning.. its stable to +/- 1 at this time when I am typing).. and this some random noise.. I think that would be a LOOSE connection @ the DP jumper.

@owais!....nice to see the results!....yes thats y i asked first for your house wiring and then the DP....this might be the issue if its still not stable! about the modem....this one is trouble free! as it has very less facilities and this hangs rarely :D

Thanks a lot firecruz, *really* appreciate it.

Sync and SNR values are unstable, but, at least, now I don't have to restart the modem (it reconnects itself).

I am also trying to get a lineman to look at DP.

Once I get these SNR values to calm down, (they change from 31 at start, and as I type, have come down to 6.0 in 3 disconnections) it will be better. Definitely it is something at DP or maybe maybe a weak pair as well.

yo welcome bro!

actually these lineman's mostly dont take of the onu circuits as they are assumed to be running perfect!....the pair thing starts from 100meters away from your house(where ONU is stalled) and to your pole and then DP.... is the DP wire change doesnt solves you need that cable pair to be changed....btw the cable from DP to onu\cabnet is callled secondary cable....just told u so that it might be useful for u in communicating them your prob!

Regards.

Thanks again. Yes, this technical jargon is very helpful :)

By the way, is the secondary pair of ONU also in the 'cabinets', the locked ones which are place at a certain distance from exchange?

As my cousin's 1 port ZTE was working perfectly, therefore, I did a little troubleshooting. THANKS TO ALLAH (like Inzi says), I have managed to make my new modem very stable now. (remember, i installed a new wire, output from filter going into the modem; somehow the moron shopkeeper didn't properly closed the end jack - it was loose; changed the pair and SNR is now in between 29 and 31 .. which is very stable enough).

Got a call courtesy PTA today; I said my complaint is resolved and also emailed PTA (CC: PTCL) thanking them for resolution :)

@firecruz: And yes, thanks a lot to you too. The problem was with the MODEM (resolved by ZTE) and one pair of cable (output from the filter).

[quote=", post:, topic:"]

Thanks again. Yes, this technical jargon is very helpful :)

By the way, is the secondary pair of ONU also in the ‘cabinets’, the locked ones which are place at a certain distance from exchange?

As my cousin’s 1 port ZTE was working perfectly, therefore, I did a little troubleshooting. THANKS TO ALLAH (like Inzi says), I have managed to make my new modem very stable now. (remember, i installed a new wire, output from filter going into the modem; somehow the moron shopkeeper didn’t properly closed the end jack - it was loose; changed the pair and SNR is now in between 29 and 31 … which is very stable enough).

Got a call courtesy PTA today; I said my complaint is resolved and also emailed PTA (CC: PTCL) thanking them for resolution :)

@firecruz: And yes, thanks a lot to you too. The problem was with the MODEM (resolved by ZTE) and one pair of cable (output from the filter).

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great…happy for u bro! and welcome :) yeah my experience with ZTE is also good ! but im sad there are no more ZTE coming now! its only huawei and shiro :(

well 1217 is inquiry

1218 is complaint…and you dont have to call exch as they dont have authority to remove complaint until the user replies to the automatic call from PTCL for quality assurance and you press ‘1’ to accept its ok! else you can call 1218 and ask them to remove as they can force to remove…both different depts!

@Owais...good to see your problem solved but just wanted to know your telephone exchange as you are using ONU.

^ Sent via Email.

I don't know what is the DAMN issue, but, after one day, it started again. (I even paid a lineman, and, he did something - not from pole, somewhere else - due to which one that day my SNR increased to 33, and was stable for WHOLE NIGHT).

The damn line is more than clear, the lineman says what more I want as everything is fine. I mean if line is bad, there must be some ounce of noise in it, there is NOT.

Sickest thing in the world!!

@owais....yar im dead sure somewhere in the path there is some re-patching done! such LOS comes only with loose connections! tell line man to check up the joints all in all for once!