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#1 August 11 2018

Kareem
Member

All of sudden, very high ADSL attenuation.

Guys, I'm dealing with a very complicated issue. Suddenly, out of the blue, my modem started syncing at 512kbps. Attention increased from 14 to 32dB.

I get frequent disonnections and the modem keeps resyncing. Ogero guys came and confirmed that the issue is with the wire going from ground floor to my apartment.

It's my parent's house, a relative old building and chaging the internal wires is out of question. The only possible solution i can think of is an external phone cable but I still prefer to fix it rather than doing some work around.

How can a 20 y old phone cable go bad all of sudden? anyone experience anything similar ?

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#2 August 11 2018

leblinux
Member

Re: All of sudden, very high ADSL attenuation.

Interference could be the issue check for electic magnetic interference I have a problem with SNR drops the connection everytime the elevator works...

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#3 August 12 2018

enthralled
Member

Re: All of sudden, very high ADSL attenuation.

leblinux wrote:

I have a problem with SNR drops the connection everytime the elevator works...

Out of topic, but every time I see a post from "the elevator guy" I crack up sarcastically. I'm in the same boat :)

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#4 August 12 2018

nuclearcat
Member

Re: All of sudden, very high ADSL attenuation.

Attenuation usually mean impedance.
Check all joints/connectors everywhere, maybe some are loose, or if you have it - might be issue with filter.

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#5 November 21 2018

leblinux
Member

Re: All of sudden, very high ADSL attenuation.

enthralled wrote:
leblinux wrote:

I have a problem with SNR drops the connection everytime the elevator works...

Out of topic, but every time I see a post from "the elevator guy" I crack up sarcastically. I'm in the same boat :)

Did you solve the elevator problem?

When the elevator compeltely powers off I get SNR downstream bumped up to 29 db from 20!

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#6 August 19 2019

masrour
Member

Re: All of sudden, very high ADSL attenuation.

same problem here , when elevator on snr goes down to 2 and 3 and connection drops , and when elevator off snr about is about 18 .. anyone solved this problem ?

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#7 August 19 2019

xazbrat
Member

Re: All of sudden, very high ADSL attenuation.

masrour wrote:

same problem here , when elevator on snr goes down to 2 and 3 and connection drops , and when elevator off snr about is about 18 .. anyone solved this problem ?

Did an external line which minimized, although not eliminated the problem.  My SNR margin was around 12 before and it went up to the low 20's after I did it, and will drop down to 10 or so if the elevator uses the full 13 floors.  Also, try to connect to g.dmt if you can---seemed to be the most stable for me, but this may depend on your current speed and connection (if >8mbps, then won't work fro you)

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#8 August 19 2019

masrour
Member

Re: All of sudden, very high ADSL attenuation.

I've done everything possible , changed the tele. line to CAT6A and put it external and also changed to G.DMT but snr keeps dropping .. idm support guy tels me that i need to put noise cancellation filter in the electric room in the building and it cost above 200$ without electrical engineer fees

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#9 August 19 2019

bobo619
Member

Re: All of sudden, very high ADSL attenuation.

masrour wrote:

I've done everything possible , changed the tele. line to CAT6A and put it external and also changed to G.DMT but snr keeps dropping .. idm support guy tels me that i need to put noise cancellation filter in the electric room in the building and it cost above 200$ without electrical engineer fees

For best results on using CAT6 DIYs is to replace the old cooper wire from the Ogero box directly to your modem without going through your building internal wires. The reason behind this is that if you use hybrid wiring (CAt6/Internal building wire) the benefit of cat6 which is to reduce cross talk interference to stabilize your connection is minimized and thus having poor results.

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#10 August 19 2019

masrour
Member

Re: All of sudden, very high ADSL attenuation.

I've putted it directly to ogero main box and also same results ,the problem is in all the electrical room , my neighbours also facing the same problem

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#11 August 19 2019

xazbrat
Member

Re: All of sudden, very high ADSL attenuation.

masrour wrote:

I've done everything possible , changed the tele. line to CAT6A and put it external and also changed to G.DMT but snr keeps dropping .. idm support guy tels me that i need to put noise cancellation filter in the electric room in the building and it cost above 200$ without electrical engineer fees

If that is the cure, see if the neighbors will chip in---any reputable firm that puts one in will test it when they install it so if it doesn't work, then you won't be stuck installing a useless item.  The ultimate solution is to ground the elevator, but that is also the most expensive.

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#12 March 27 2020

Kareem
Member

Re: All of sudden, very high ADSL attenuation.

A quick follow up. It was solved back in time by using an external telephone line. Now a quick observation :

When electricity is on ( EDL or generator ) :
   
Downstream                Upstream               
Actual Rate    17261    Kbps    935    Kbps
Attainable Rate    17420    Kbps    968    Kbps 

During a power outage which lasts maximum 2 minutes.

   
Downstream                Upstream               
Actual Rate    17261    Kbps    935    Kbps
Attainable Rate    21924    Kbps    977    Kbps.


That's almost 4.5 mbps of difference. I did few tests and it looks like the apartment electricity was not the culprit. It has to do with the building.

I tried with the concierge to disconnect all the apartments from power so that the elevator only gets power from the generator ( impossible to disconnect the elevator as it's directly connected to the generator ) and it looks like the sync rate remained at  17mbps.

Only when everything is switched off, the sync rate goes back to 20+mbps.

Now this might be something normal but I don't think 7-8dB of additional attenuation is something I can digest specially when I'm thinking of moving to VDSL2.

Has anyone experienced an attenuation as high as that? It's worth mentioning that the elevator operation doesn't seem to affect the results. Whether on standby or operating, the attenuation is the same.

Last edited by Kareem (March 27 2020)

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#13 March 27 2020

nuclearcat
Member

Re: All of sudden, very high ADSL attenuation.

Might be everything of all, noise of powerlines, appliances connected to it (most shitty stuff sellers getting to Lebanon has no certifications), even just shitty triac water heater can make power line noisy as hell.
Interference is terrible thing.
Once wifi rates in apartment was dropped due crappy CFL lamps owner installed.
Another example, critical site in one of exUSSR countries, we had to sweep one city block to find old guy with malfunctioning TV that was causing interference to huge satellite dish 8km away.

Did you try following things:
1)Put modem in box with small UPS (maybe DC ups, if u will find it)
2)Get with laptop to telephone cables box, find yours
3)disconnect telephone wires going to apartment
4)connect to box, your telephone wires, check speed
5)just connect back wires to apartment, check speed

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#14 March 28 2020

Kareem
Member

Re: All of sudden, very high ADSL attenuation.

nuclearcat wrote:

Might be everything of all, noise of powerlines, appliances connected to it (most shitty stuff sellers getting to Lebanon has no certifications), even just shitty triac water heater can make power line noisy as hell.
Interference is terrible thing.
Once wifi rates in apartment was dropped due crappy CFL lamps owner installed.
Another example, critical site in one of exUSSR countries, we had to sweep one city block to find old guy with malfunctioning TV that was causing interference to huge satellite dish 8km away.

Did you try following things:
1)Put modem in box with small UPS (maybe DC ups, if u will find it)
2)Get with laptop to telephone cables box, find yours
3)disconnect telephone wires going to apartment
4)connect to box, your telephone wires, check speed
5)just connect back wires to apartment, check speed


Did you try following things:

1)Put modem in box with small UPS (maybe DC ups, if u will find it)

           Modem connected to online sinewave UPS

2)Get with laptop to telephone cables box, find yours

          I have the wire labeled by Ogero tech.

3)disconnect telephone wires going to apartment

        Disconnected now from the box.


4)connect to box, your telephone wires, check speed

       Almost same attenuation, 0.6 dB difference.


5)just connect back wires to apartment, check speed

     
OK so it looks like the telephone line is not to blame. It's the telephone box that is experiencing some kind of interference. 

Today at 9 AM, i waited for the power outage and checked the attenuation at the telephone box in the building.

8 :59 AM   : Attenuation 22 dB ( EDL )
9: 00 AM   : Power outage for 1 minute before generate kicks in - Attenuation 13 dB
9: 01 AM   : Generator online - Attenuation 22 dB

So back to square one and yeah, 9 dB interference is f****ng a lot.

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#15 March 28 2020

wollyka
Member

Re: All of sudden, very high ADSL attenuation.

Kareem wrote:
nuclearcat wrote:

Might be everything of all, noise of powerlines, appliances connected to it (most shitty stuff sellers getting to Lebanon has no certifications), even just shitty triac water heater can make power line noisy as hell.
Interference is terrible thing.
Once wifi rates in apartment was dropped due crappy CFL lamps owner installed.
Another example, critical site in one of exUSSR countries, we had to sweep one city block to find old guy with malfunctioning TV that was causing interference to huge satellite dish 8km away.

Did you try following things:
1)Put modem in box with small UPS (maybe DC ups, if u will find it)
2)Get with laptop to telephone cables box, find yours
3)disconnect telephone wires going to apartment
4)connect to box, your telephone wires, check speed
5)just connect back wires to apartment, check speed


Did you try following things:

1)Put modem in box with small UPS (maybe DC ups, if u will find it)

           Modem connected to online sinewave UPS

2)Get with laptop to telephone cables box, find yours

          I have the wire labeled by Ogero tech.

3)disconnect telephone wires going to apartment

        Disconnected now from the box.


4)connect to box, your telephone wires, check speed

       Almost same attenuation, 0.6 dB difference.


5)just connect back wires to apartment, check speed

     
OK so it looks like the telephone line is not to blame. It's the telephone box that is experiencing some kind of interference. 

Today at 9 AM, i waited for the power outage and checked the attenuation at the telephone box in the building.

8 :59 AM   : Attenuation 22 dB ( EDL )
9: 00 AM   : Power outage for 1 minute before generate kicks in - Attenuation 13 dB
9: 01 AM   : Generator online - Attenuation 22 dB

So back to square one and yeah, 9 dB interference is f****ng a lot.

Check if someone in building install new LED or lighting. It happened to me and the restaurant below in the same building has installed new lighting that was affecting the phone box.

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#16 May 16 2020

Kareem
Member

Re: All of sudden, very high ADSL attenuation.

Ok so I'm officially joining the elevator drama club.  I am stuck with three types of interference and I am not able to solve any at the moment.

Every since I switched to VDSL, the line quality has become more and more sensitive which is expected.

I have a CAT6 cable ONLY going from the box to the VDSL modem. It's an external line in a shaft with no cable however the shaft is right beside the elevator room so there's a 20 cm wall block and 4 meters void between my cable and the lift.


What I'm struggling with :

1- Any time the elevator is used, my SNRM drops 5dB. The modem won't disconnect unless it's going through more than 5 floors.
2- My Attainable rate is 30% lower everynight after 10:30 PM until 7:30 AM  ( give or take ) and I have no clue.
3- My last interference is certainly not from our building. When electricity goes, my downstream rate goes 4-5 Mbps up. Even when the generator kicks in but then a minute later or so it will go down again.

Any solution for the elevator thing? my 2nd issue is also very difficult to trace; as for the 3rd one I'm positive that it's nothing to do with our building but go convince Ogero.

Ironically my neighbors also reported random disconnections from Ogero during the day mainly and they're on ADSL but not everyone cares.

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#17 May 16 2020

leblinux
Member

Re: All of sudden, very high ADSL attenuation.

Hint that CRCs on download build up way much then on the upload... I was hoping that Fiber would solve our problems...

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#18 May 17 2020

xazbrat
Member

Re: All of sudden, very high ADSL attenuation.

Kareem wrote:

Ok so I'm officially joining the elevator drama club.  I am stuck with three types of interference and I am not able to solve any at the moment.

Every since I switched to VDSL, the line quality has become more and more sensitive which is expected.

I have a CAT6 cable ONLY going from the box to the VDSL modem. It's an external line in a shaft with no cable however the shaft is right beside the elevator room so there's a 20 cm wall block and 4 meters void between my cable and the lift.


What I'm struggling with :

1- Any time the elevator is used, my SNRM drops 5dB. The modem won't disconnect unless it's going through more than 5 floors.
2- My Attainable rate is 30% lower everynight after 10:30 PM until 7:30 AM  ( give or take ) and I have no clue.
3- My last interference is certainly not from our building. When electricity goes, my downstream rate goes 4-5 Mbps up. Even when the generator kicks in but then a minute later or so it will go down again.

Any solution for the elevator thing? my 2nd issue is also very difficult to trace; as for the 3rd one I'm positive that it's nothing to do with our building but go convince Ogero.

Ironically my neighbors also reported random disconnections from Ogero during the day mainly and they're on ADSL but not everyone cares.

1) Same here, but doesn't disconnect as much as my snr margin is pretty healthy during the day near 14 (but speed sucks).  My max attainable speed effectively doubled when I used an external Cat6 cable.  What can be done---make sure that there is an emi filter on the elevator and hopefully your building is also grounded for max efficiency (used to be $1000-$1200 for the filter, now who knows).  In my building, there is also a water pump.  That reduces my max attainable by some 40% too and disconnects me when if first starts.

2) I have a similar issue and I am pretty sure it is the building lights.  I noticed one day that the natour did not turn off the lights pretty late (11ish am) and I was getting the same reduction in speed.  When I came back, lights were off and my speed was back to normal.

3)  This could be anything---a fridge or AC starting up and it doesn't need to be in your apartment.  Maybe someone has a voltage stabilizer somewhere near the telephone lines down in the electricity room.

Frustrating to find these things out as proper grounding would take out a lot of these issues at the beginning.

Last edited by xazbrat (May 17 2020)

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#19 May 18 2020

Kareem
Member

Re: All of sudden, very high ADSL attenuation.

Has anyone tried something like this? I have some cash to burn but I don't really wanna rush.

c85e5fcc59b357af8ed25658d9faf30c.png

Thing is even with CAT6 the SNR and the attainable rate at the building box is higher. Say If I install this at the box, would that be helpful to maintain a stable low SNR without disconnections or interference?

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#20 May 18 2020

wollyka
Member

Re: All of sudden, very high ADSL attenuation.

Kareem wrote:

Has anyone tried something like this? I have some cash to burn but I don't really wanna rush.

https://i.gyazo.com/c85e5fcc59b357af8ed … faf30c.png

Thing is even with CAT6 the SNR and the attainable rate at the building box is higher. Say If I install this at the box, would that be helpful to maintain a stable low SNR without disconnections or interference?

Did you find one in Lebanon? See my post at Ogero thread for a similar problem.
One engineer suggested that for me but he said it is without guarantees, it may help and it may not.

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#21 May 18 2020

Kareem
Member

Re: All of sudden, very high ADSL attenuation.

I can buy one on  the internet but I'm hesitating. Better if I can install it even before the telephone box.

There are conditions that should be met for this to be effective :

ce89f515d884bff969fe5cc882928b1c.png

L1 is the line coming from the CO. I am not sure if the line is 26 AWG or 28 AWG since it's very thin and oxidized.

68cf86e1f24e8347dc77922422673066.png

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#22 September 15 2020

ozone1864
Member

Re: All of sudden, very high ADSL attenuation.

Hi Guys,
After 1 year and a half struggling with snr drops.
Today I found out its elevator problem.
Tomorrow ogero will visit me any suggestions ?
Anyone solved similar problem in the past ?
Note: problem is on ogero box too affecting all building.

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#23 September 15 2020

Idler
Member

Re: All of sudden, very high ADSL attenuation.

I had an issue lately and i worked so hard with the ogero guy, first of all i was on fastpath and it was unstable due some electrical stuff i tried all the above changing cables trying directly from box with 1 meter cable to the machine anything you can think of some issues were:
generator cable was hanging very close to the telephone box
at the spreader across the street (mwazi3) he connected my line directly to the coming one instead of passing through a junction
then i switched from fastpath to interleave now my internet is stable at 4mbps

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#24 September 16 2020

ozone1864
Member

Re: All of sudden, very high ADSL attenuation.

Guys after investigation, my problem with elevator started when the people living in the building decided to make the elevator work with the generator. So they bought an electric inverter which convert triphasé to monophase.
I called the elevator maintenance guy and he said that this inverter causes a hell of interference.
But the thing is that this inverter is located on the roof while ogero box is located in the ground floor.

Everytime someone uses the elevator  no matter if EDL or Generator, the problem occurs.

Last edited by ozone1864 (September 16 2020)

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#25 September 16 2020

nuclearcat
Member

Re: All of sudden, very high ADSL attenuation.

They need to install proper filters, probably inverter made in lebanon and has no compliance with electromagnetic emission standards.

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