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[NewtronStar]

if you try again I would look to see if the CRC's rather than the ES change.  I found the odd CRC spikes (only giving one ES) had the number of CRC in the spikes markedly reduced.

Cheers les-70 I it was facinating running the modem on battery power though my testing was during the quiet time 1am to 6am which was not a good test, yet i'll be honest kind of worried with all the modem off's and on's the DLM will intervene on this weird fastpath + interleaved line.

And getting this modem reboot right due to strange DS SNRm swings is just adding to the  complexity to keep the errored seconds away from the red zone.

EDIT: back on battery power at 18:28 i'll let it run for a 24 hour period if the battery holds that is.

[NewtronStar]

So back to the SNRM swing it's not the mains it's not the internal wiring and it's not the BT pair their line shows only 1 omh of a difference.

So how is this RFI getting into my Modem (HG612) if it's none of the above 
Could the RFI be infiltrating the modem via the electronic components inside and this seems to be a reasonable theory, as if you remember back to the old tv's the tuner section was sheilded and earthed from the rest of the circuitry this was to isolate any other RFI inside the TV getting to the tuner.

So some sensitive components inside the HG612 may not be shielded from outside RFI 

[les-70]

 I am not sure which specific issue is concerning you. Generally all lines pick up RFI along their full length from the DSLAM.  Twisted pair is not perfect so differential pick up occurs and RFI tends to be worse with overhead cables.  A common mode filter as in Mark 2 or 3 will attenuated common mode noise but with have no impact on differential noise.

   Your SNRM shows an evening drop which is normal in residential areas but varies in degree.  The drop is usually a mixture of max cross talk with most lines connected and also most other electrical devices switched on, and also on and off.  A mains filter might have reduced some of your errors if any are due to noise on the mains but I think you said that you only tested the battery during the quiet night hours.  If so a day time test when errors are higher would be of interest.

[NewtronStar]

I am not sure which specific issue is concerning you. Generally all lines pick up RFI along their

Yes understand Les-70 it's I have to give up 3000kbps on the DS to keep the SNRm close to 6dB in the evenings and yes can see a few others with the day time and evening SNRm swings due to RFI just can't find out why some lines have it an others do not 

Yet their are some MDWS user's who have an even longer line than myself who's DS SNRm is steady 24/7 ie: only swinging by 0.5dB

[NewtronStar]

Well the good news is the radio propagation has started to shift it's time again as the sun is now setting later each evening and the effects of RFI don't start coming in until 16:45 where as it's been 15:20 for the last 3 months.

Its kind of funny we look forward to the summer for light and heat yet my modem enjoys the extra daytime hours even more 

[les-70]

  The ES max counts on your line match peak time home internet and electrical appliance use and on/off's.  I can't  see the timing of your ES's changing on MDSWS and they are a minimum soon after midnight.  The timing of RFI may well be visible in the tones but I wonder if broadcast radio based RFI is really your lines problem.

[NewtronStar]

but I wonder if broadcast radio based RFI is really your lines problem.

It's difficult to convey Les, internal electirical home appliances do put a strain on the modem but the external RFI then makes things much worse.

I can tell you those shortwave broadcasting stations don't help one bit in the SNRM as it just adds more noise into the normal household evening accumulation of noise.

Now the guys who live close to the PCP cabinet don't have to worry to much about evening RFI from shortwave as the line will have a much stronger signal to the modem and drown out the effects of RFI.

The Longer line has a lessor signal so any strong shortwave stations will be picked up as noise and the SNRM will fall as the propagation gets stronger after sunset.

It's definitely shortwave broadcasting radio stations that cause my SNRM to drop and rise.

you can see in the graph by the pointer the start of shortwave radio propagation.

http://en.wikipedia.org/wiki/Shortwave_radio

[les-70]

 As far as the SNRM is concerned I agree that broadcast radio RFI looks to be the likely issue.  My comment concerned the ES rates, the RFI won't be helping the ES  but to me it looks like broadcast radio is not your biggest ES cause, the ES timing does not look a good match to SNRM.  You might want to try overlaying the SNRM and ES rates to see how well one explains the other or not.

[burakkucat]

N*Star, having followed the progress of everything that you have done over the last few months, I don't think there is anything else you now can do.    You have taken steps to eradicate (or minimise) all local sources of interference to your circuit. It is just unfortunate that your location appears to be optimally placed to receive those broadcast transmissions via reflections between the ionosphere and the Earth and that no practical differential circuit will fully reject a common-mode signal. 

We must remember that any xDSL service in the U.K. is provided on a "best effort" basis and what you currently receive is the best that Beattie Bellman's Openreach can provide.

[NewtronStar]

It is just unfortunate that your location appears to be optimally placed to receive those broadcast transmissions via reflections between the ionosphere and the Earth and that no practical differential circuit will fully reject a common-mode signal. 

Your right of course and have fully accepted the cause and the effect it has on my broadband, I am just doing my best to inform other users out there what the symptoms look like incase others fall into this never ending loop 

[burakkucat]

Yes, I understand. (It's rather like chasing one's own tail!) 

[NewtronStar]

Yes, I understand. (It's rather like chasing one's own tail!) 

Though I am getting concerned with TBailey2 SNRM swings they are to low and could trigger the DLM if it hasn't already 

But I do have a suggestion and that is to resync the FTTC modem when the SNRM is at it's lowest point it will lower the sync but the SNRM will be restored close to the 6dB target margin.

[burakkucat]

Obviously the SNRM swing itself would not concern the DLM but it is the subsequent CRCs, FECs and ES' when the margin drops to a lower level. It is surprising just how many CRCs my circuit experiences when the SNRM drops to between 3.0 & 3.5 dB (DS). (For me, of course, it is just an inconvenience as the only result is an increase in the time any action takes . . . Not having any form of DLM monitoring my circuit.    )

I haven't looked at Tony's statistics because I am still monitoring big360's circuit but I could use all four panes that are available in MWDS . . .

[NewtronStar]

Had to large BT van's doing stuff in another manhole cover to-day at around 1 pm it seems what ever they were doing this time caused the VDSL2 to resync at 2pm, I must have two crosstalk user when looking at SNRM graph.

Kind of getting sick and tired of syncing the modem when the SNRm is at it's lowest point to keep the SNRm close to 6.0dB as i just don't like getting close to 5dB but I don't if it would harm the the current profile 

[burakkucat]

To be honest, I'm not sure what to make of your graph where it shows a couple of stalagmites.