LebGeeks

Truepeace

Member

Errors and DC issues. Any electrician recommendation?

Any electrician recommendation to troubleshoot my issue? My home electrician is out of known and I have no idea how to find a knowledgeable electrician.
Problem: I am getting random disconnections and high bursts of CRC errors.
CRC errors get drastically reduced when I have my phones disconnected although I had filters on all phones and modem.
Disconnections still happen sometimes when my phones are disconnected. I used to avoid them by using g.dmt modulation before it got blocked.

I think Ogero technicians checked my phone line many times from their side and probably found nothing.
So their twitter account suggested me to check my electrical lines which they can't provide an electrician for.
Any recommendation?
Thanks.

Last edited by Truepeace (October 9 2017)

tmash2

Member

Re: Errors and DC issues. Any electrician recommendation?

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Last edited by tmash2 (February 21 2021)

Truepeace

Member

Re: Errors and DC issues. Any electrician recommendation?

I had two cases throughout the years in terms of having DC issues and CRC sum errors. In Lebanon, I had to use one of the built in shielded Ethernet sockets as telephone line due to bad wiring. In KSA, I had cheap brand name CFLs that affected the performance with SRA enabled, and DCs without, SNR was flactuating. I don't understand why G.DMT is blocked, I'm using it without probs here, interleaving seems to be off by default as well on this modulation. Can you post line stats?

I did not understand the first half of your post sorry, either ways I think it is an electrician's job to do it. After I asked why g.dmt was not working anymore the technician on the phone said "Who told you about it first? it causes problems on our lines so we blocked it"...
I have interleaving off too, putting it back on did not help. Line stats currently:
                          Downstream    Upstream    
SNR Margin       14.9              10.1    db
Line Attenuation 37.8              21.7    db
Data Rate           4095             1023    kbps
Max Rate            8688              996    kbps
POWER             19.4              12.2    dbm
CRC                   9181              458

Last edited by Truepeace (October 9 2017)

hkbazzi

Member

Re: Errors and DC issues. Any electrician recommendation?

I had two cases throughout the years in terms of having DC issues and CRC sum errors. In Lebanon, I had to use one of the built in shielded Ethernet sockets as telephone line due to bad wiring. In KSA, I had cheap brand name CFLs that affected the performance with SRA enabled, and DCs without, SNR was flactuating. I don't understand why G.DMT is blocked, I'm using it without probs here, interleaving seems to be off by default as well on this modulation. Can you post line stats?

I did not understand the first half of your post sorry, either ways I think it is an electrician's job to do it. After I asked why g.dmt was not working anymore the technician on the phone said "Who told you about it first? it causes problems on our lines so we blocked it"...
I have interleaving off too, putting it back on did not help. Line stats currently:
                          Downstream    Upstream    
SNR Margin       14.9              10.1    db
Line Attenuation 37.8              21.7    db
Data Rate           4095             1023    kbps
Max Rate            8688              996    kbps
POWER             19.4              12.2    dbm
CRC                   9181              458

was there no difference in SNR when you turned interleaving back on? Did it still drop just as frequent?

Last edited by hkbazzi (October 9 2017)

Truepeace

Member

Re: Errors and DC issues. Any electrician recommendation?

was there no difference in SNR when you turned interleaving back on? Did it still drop just as frequent?

The CRC errors were still very high for sure and I don't remember not having the dc/reboot issues so I told them to put it back off for the ping. The only thing that may have changed was the max rate being higher with interleaving.

Last edited by Truepeace (October 10 2017)

GeorgesHanna

Member

Re: Errors and DC issues. Any electrician recommendation?

what modem you have?

Truepeace

Member

Re: Errors and DC issues. Any electrician recommendation?

what modem you have?

Tp link td-w8961n, bought newly (firmware v3).

tmash2

Member

Re: Errors and DC issues. Any electrician recommendation?

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Last edited by tmash2 (February 21 2021)

Truepeace

Member

Re: Errors and DC issues. Any electrician recommendation?

[
Your SNR margin on downstream is too low, remember SNR =/= SNR Margin, basically the higher SNR margin the better, the lower SNR the better.

CFL are fluorescent bulbs, what I meant by ethernet socket is the built-in in-house ethernet wiring, ethernet cables have better insulation and provide better data integrity compared to old phone lines, have you tried turning off the entire main electricity in your house while running the modem on UPS?
You can post the stats while doing this, could help the diagnoses.

Edit: I should add that your router seems to use trendchip adsl ic, which isn't a problem unless you're too far from the CO.

AFAIK we don't have the old CFL lights. I already tested for electrical interference by shutting down the electricity from my house from the home's switch and the line stats did not change, didn't game while electricity is off though, is it worth the hassle if my previous testing got me no results? I wanted to test tough to game while someone used the elevator but I did not have the chance to do it.

GeorgesHanna

Member

Re: Errors and DC issues. Any electrician recommendation?

get a d-link router

leblinux

Member

Re: Errors and DC issues. Any electrician recommendation?

I am having same problems with CRCs and SNR drops, and today I found out its due to the Elevator of the building! Don't ask me why... !

When the elevator moves my SNR drops from 25 to 3 and CRCs gets buildup...

Last edited by leblinux (October 15 2017)

tmash2

Member

Re: Errors and DC issues. Any electrician recommendation?

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Last edited by tmash2 (February 21 2021)

Adnan

Member

Re: Errors and DC issues. Any electrician recommendation?

I am having same problems with CRCs and SNR drops, and today I found out its due to the Elevator of the building! Don't ask me why... !

When the elevator moves my SNR drops from 25 to 3 and CRCs gets buildup...

Wow, I finally found someone that has the same problem as me! Do you happen to have ishtirak on the elevator? Get an AM radio and tune it to around 600kHz and hear the magic.

Here's a video I recorded : https://m.youtube.com/watch?v=nGo97T0v7Wk

Adnan

Member

Re: Errors and DC issues. Any electrician recommendation?

I can see two options here, switch to VDSL if possible (much higher frequency) or replace phone wires with shielded cable.
Quick googling "adsl elevator" surprised me as this issue seems to be popular. (elevator power supply RF noise at 1.2mhz which is typically the center freq. of adsl2 and adsl2+, g.dmt is slightly below)

I've been thinking about getting a shielded cable. Are you sure it can solve this problem?

tmash2

Member

Re: Errors and DC issues. Any electrician recommendation?

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Last edited by tmash2 (February 21 2021)

leblinux

Member

Re: Errors and DC issues. Any electrician recommendation?

Great thanks! However I also had a faulty cable from inside home to one of the telephones, so disconnectig the faulty phone line from the main switch of the house solved much the CRCs, I am now left with the Elevator problem also its because of the EMF its sending and yes its Eshitirak with a special device installed the eleavtor shaft at the roof and I think its causing this...

Adnan

Member

Re: Errors and DC issues. Any electrician recommendation?

Definitely, same problem. If you happen to install a shielded cable please inform us of the outcome.

leblinux

Member

Re: Errors and DC issues. Any electrician recommendation?

I can see two options here, switch to VDSL if possible (much higher frequency) or replace phone wires with shielded cable.
Quick googling "adsl elevator" surprised me as this issue seems to be popular. (elevator power supply RF noise at 1.2mhz which is typically the center freq. of adsl2 and adsl2+, g.dmt is slightly below)

I've been thinking about getting a shielded cable. Are you sure it can solve this problem?

The thing is I took today the router and went straight down to the post inside the building electrical room, hooked it on my line directly and monitored SNR as we pressed the elevator and still it affects SNR, I think the whole building is affected with EMF!
Depressing...

leblinux

Member

Re: Errors and DC issues. Any electrician recommendation?

Definitely, same problem. If you happen to install a shielded cable please inform us of the outcome.

Try what i did, connect router to electic room of the building directly to Ogero's box and have someone pull the elevator let me know if SNR drops

leblinux

Member

Re: Errors and DC issues. Any electrician recommendation?

I ended today by getting a telephone cable and installed it externally through my building shaft and directly to home.
Also isolating one of the faaulty telephone lines inside my home.
Results:
SNR 23
CRC 0

when elevator works SNR drops to 15 which is still acceptable and CRCs to 1 or 2 max until the elevator stops SNR bumps to 22-23.

Before today SNR used to drop to 3 and 5 with 30000 CRCs

tmash2

Member

Re: Errors and DC issues. Any electrician recommendation?

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Last edited by tmash2 (February 21 2021)

Adnan

Member

Re: Errors and DC issues. Any electrician recommendation?

Definitely, same problem. If you happen to install a shielded cable please inform us of the outcome.

Try what i did, connect router to electic room of the building directly to Ogero's box and have someone pull the elevator let me know if SNR drops

Did that à few weeks ago. The ogero box is in the first floor and it is not affected by the EMF. The device causing the EMF is in the elevator room in the seventh floor and I live on the 5th.

It's practically impossible to get the cable through a different route so if a shielded cable can work I'll get one.

Last edited by Adnan (October 15 2017)

Truepeace

Member

Re: Errors and DC issues. Any electrician recommendation?

I recorded my router's stats while using the elevator which turned out to be affecting my line too!
CRC errors jumped from 933 to 1529 to 2151 and the SNR margin used to reach at some points 0.1.
So is the only solution replacing the phone lines with Cat6 cables if I don't plan to switch to VDSL? And why is this happening at only my house and not others? Maybe because the phones lines which are not shielded are running very close to the electrical lines?

Last edited by Truepeace (October 17 2017)

Adnan

Member

Re: Errors and DC issues. Any electrician recommendation?

The phone lines don't even have to be close to any electrical cable. It's all due to the huge electromagnetic field generated by some device used in the elevator room. Go upstairs and check it out.

tmash2

Member

Re: Errors and DC issues. Any electrician recommendation?

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Last edited by tmash2 (February 21 2021)