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#26 July 16 2017

H.S
Member

Re: How to improve my connection's stats? (SNR margin)

jazzzar wrote:

I'm using electric cables like the one in the pictures of Raficoo for phone and dsl, why is it bad? My snr margin is above 6db but getting lots of CRC after the upgrade from 1Mbps to 4Mbps, does changing it to CAT6 fix this problem?

They are not bad per-se, to get the most out of a DSL line, using a twisted pair is highly recommended for optimal performance and decreasing noise as much as possible. Having high CRC count might not be from the cable or from your end. The upgrade is still new and still in the adjusting phase, so it might get better in the upcoming days.

For those who are worried about the cable surviving outdoors, you can install the cable inside an electrical tube. There are thin/gray electrical tubes and they're cheap. I installed the exposed part (which is at the roof) inside one of these tubes and it is perfectly protecting the cable from sunlight.

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#27 July 16 2017

nuclearcat
Member

Re: How to improve my connection's stats? (SNR margin)

The biggest problem is to analyse how much wiring affecting your connection. Easiest way, by hooking modem directly to box.
Best - by detaching wire from telephone box, checking impedance, hooking oscilloscope/spectrum analyzer to check the noise and TDR to check cabling.
And full line testing guide is like this: http://media.klinkmann.lv/pdf/lv/exfo/E … _Guide.pdf

Regarding cable, i believe CAT3 is fine, DSL frequencies is well below it's limits. In your case first one (and i believe cheapest) 2 PR (2 pairs), but nothing stated there about UV resistance and etc.
Using non-outdoor cable for outdoor installation is just render cabling having short time and degradation of cable parameters after while, depends how much it is exposed to sun. As a hack, at least to hide it from UV you can put a cable inside some UV resistant flexible pipe/conduit.

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#28 July 17 2017

Hassan
Member

Re: How to improve my connection's stats? (SNR margin)

So I had a technician at my house a few minutes ago to take care of rewiring my cables from the connectivity box downstairs to my house. I have 3 points to discuss/inquire about:

He first measured the voltage of the phone cable once it reaches the house. The value turned out to be 55V and there was no noise when he picked up the phone. So he said that my wiring is very good and there is no need to do anything. Could someone with some knowledge in this field elaborate whether this is true or not based on the voltage value he got ?

Anyways I told him that I don't mind rewiring as the worst that could happen is for line quality to remain the same. So He recommended using a cat5e F/UTP cable since cat6 is not worth the increase in price for my case (note that most of the wiring will be outdoors and in some cases passing near electrical wires). Now despite telling him that I read that these kind of cables need to be grounded or else they would do more harm than good. He insisted that this is true for STP cables only and not FTP. I am personally not convinced by what he said but again, can someone elaborate on the accuracy of that?

Another point I'd like to discuss is that every time I asked him to try to decide on another path to avoid passing near electric wires (I was considering going internally instead of outdoors), he would say that they won't cause any issue since they won't be passing in parallel for a long distance and that the foil will help minimize their interference. He would also say the usual: this is bad for house asthetics since I live in a 70 year old house so all of the wiring is visible (not hidden inside the wall or something)

Last edited by Hassan (July 17 2017)

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#29 July 17 2017

nosense
Member

Re: How to improve my connection's stats? (SNR margin)

so should we get utp, ftp, or sftp cables for outdoor installation ? I plan to just throw the cable all the way down from my balcony to the telephone box, I live on the 10th floor.

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#30 July 17 2017

anayman_k7
Member

Re: How to improve my connection's stats? (SNR margin)

Not sure if measuring voltages can tell the effect of an electrical interference, when there is an electrical interference the voltage could increase and not decrease because the magnetic field will be translated into power inside the copper line, as you know the internet carried over the analog phone cable is modulated (hence why we call the device Modem: Modulator - Demodulator), so the modulated binary data over the phone line will get modified by interference and they will became altered data that can't be corrected to their original form, a small checksum is used to validate each received data and in case of error the source will be requested to resend this segment

adsl-adsl2-adsl2-etc-24-638.jpg?cb=1404792953

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#31 July 21 2017

nosense
Member

Re: How to improve my connection's stats? (SNR margin)

aliessayli2 wrote:

so should we get utp, ftp, or sftp cables for outdoor installation ? I plan to just throw the cable all the way down from my balcony to the telephone box, I live on the 10th floor.

bump
@nuclearcat I appreciate it if you can help me out.

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#32 February 18

Techlover
Member

Re: How to improve my connection's stats? (SNR margin)

Hi guys,
So any update? Which cables you found to be the best to put outdoor ?

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#33 February 18

anayman_k7
Member

Re: How to improve my connection's stats? (SNR margin)

Personally I am using STP Cat7 which was unnecessary, a normal UTP would have done the job well
Note: using 1 pair only from the available 4 pairs

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#34 February 18

Techlover
Member

Re: How to improve my connection's stats? (SNR margin)

anayman_k7 wrote:

Personally I am using STP Cat7 which was unnecessary, a normal UTP would have done the job well
Note: using 1 pair only from the available 4 pairs

What brand are you using ?
And is STP grounded ?

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