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Lumpy QLN graph = crosstalk ?

FIXED
mikemod
Dabbler
Posts: 19
Thanks: 3
Registered: ‎05-09-2016

Re: Lumpy QLN graph = crosstalk ?

Just looking through your thread and I seem to have similar issues, very rural and a long line.

This is my SNR from about 10.00 this morning.

 

 

hitchhiker43
Aspiring Pro
Posts: 201
Thanks: 30
Fixes: 4
Registered: ‎06-07-2016

Re: Lumpy QLN graph = crosstalk ?

Hello Mike thanks for the interesting post, my god it looks like a rollercoaster! But I would agree it could well be a similar problem although yours is somewhat continuous at least at that time.

It could be interference from the power cables as mine is, there's also a 1db drop towards 4pm was it getting dark ?

I suggest looking at the routing of your phone wires carefully and see if they run parallel to any power cables for more than a meter or so, also get your radio out and see if you can hear anything, in my case on MW about 400-550M you may need to get close to the power cables to get it.

Good luck in finding it, I know just how tough it is Smiley

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mikemod
Dabbler
Posts: 19
Thanks: 3
Registered: ‎05-09-2016

Re: Lumpy QLN graph = crosstalk ?

I had a REIN issue about 8 months ago which took six months to convince OR but it was eventually found and sorted.

This new problem seems to have started after the area was struck by lightning frying pretty much everyone's router on my road.

There is  parallel power run on my road for about 100m but OR will do nothing about it.

Also my DP needs completely rewired as it is a mess according to another OR engineer but that has been raised for about 18 months with no action.

I am tired of continually chasing OR as they are next to useless at trying to fix the issue, I even went to my local MP who contacted someone senior in BT but still no  action.

Here is my QLN, not actually sure what it shows and my ES/Hour

 

hitchhiker43
Aspiring Pro
Posts: 201
Thanks: 30
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Registered: ‎06-07-2016

Re: Lumpy QLN graph = crosstalk ?

Hi Mike, do you know what they found ?

Well 100M might be ok as long as they are spaced well apart, I would hope for that distance at least a meter, preferably two!

DP may not be the problem as long as it has proper twisted pair jumpers (never seen one without) BUT if its a mess you might be on a split pair, meaning a single wire in two different pairs, a real disaster.

Long lines suffer from impairments most people dont see, do you know what your downlink loss is, mine is 53.5dB best thing is keep records and nail them into the Pnet fault reporting system and dont let them clear the ticket!!

OK your QLN looks a bit worse than mine (enclosed) but your errors are lower as your running ~6dB and I am running ~3dB snr (errors also enclosed) have a go also at checking your HLOG it should look more or less like mine (enclosed).

Finally I dare to mention your internal wiring, test socket etc!!

Regards

Roger

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mikemod
Dabbler
Posts: 19
Thanks: 3
Registered: ‎05-09-2016

Re: Lumpy QLN graph = crosstalk ?

Hi Roger,

they claim they tracked it down to an old television, I had narrowed the search area by walking the line with my AM radio.

I doubted this as it was on and off for specific times, exactly one hour, exactly two hours and was much worse at night.

I have included my HLOG, seems to terminate quicker than yours but my DS Attenuation is 63dB, not good.

At the moment the line is pretty stable during the night but seems to be affected with sun and warm days, all overhead lines from the green cabinet.

I had been through all the test socket, wiring etc.. In fact it got to a stage the last time that I ran the Modem from a UPS and switched off the supply to the entire house just to prove it wasn't me.

Currently running a MK3 faceplate with nothing but the modem connected and no extension wiring.

hitchhiker43
Aspiring Pro
Posts: 201
Thanks: 30
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Registered: ‎06-07-2016

Re: Lumpy QLN graph = crosstalk ?

OMG 63dB! have you checked with the Kitz calculator that you get roughly the right line length ? you could have an excessive attenuation due to some physical problem, however of course that makes your line even more susceptible to rfi and induction than mine. One thing I did discover recently after cutting up a piece of my newly installed latest sexy drop cable is the telco twist rate is [-Censored-] for data being only one twist every 4-6" compared with cat5 at ~2twists an inch (sorry means more to me than mm lols).

Fantastic you managed to localize yours with a radio, every attempt I have made it just seems too strong like the whole village is bathed in overwhelming signal as I said before I feel like I am inside a metricwave oven lols I should thank god mostly it only lasts 5 minutes but it isnt long enough for serious localization.

Well yup your HLOG is fine with no spikes and I guess normal for that attenuation. You mention sun and warm days, solar panels ? faulty or [-Censored-] GTI's can do bad things both for conducted and radiated emissions particularly as you mention night time is stable (are you going to admit to having a personal out of control solar farm lols).

Well obviously its not your internal wiring and you sound a really switched on guy so I am running out of ideas EXCEPT trying the same as me and beating the power distribution peeps up if in some way you can prove its induction, perhaps by winding a few turns of the horrible untwisted modem cable around a mains cable and inspecting the results!! BTW you can get twisted RJ45 leads for a few quid from the bay, just check the right pairs are twisted Smiley

Best luck

Roger

 

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hitchhiker43
Aspiring Pro
Posts: 201
Thanks: 30
Fixes: 4
Registered: ‎06-07-2016

Re: Lumpy QLN graph = crosstalk ?

omg this site is truly puritanical it censored [-Censored-] lols

what other engineering terms doesn't it like, lets try gnats [-Censored-]!

hahaha beautiful well i wont spell it out for non-engineers as the engineers know the answer hahaha

Thank you Plusnet for adding some amusement to my life :):):)

Ohh dear I just realized I dont suppose this fun will last as the nasty human moderators will come along and spoil the fun ho hum!

Moderator's note by Mike (Mav): Avoidance of swear filter edited as per Forum rules.

Tp-link W8960n on longgggggggg line!