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[burakkucat]

ATM I just need to figure out where the closest usable earth point is.

I'm sure I don't need to mention (considering your training and qualifications) that a good silent earth is what you really require rather than the house mains wiring earth/neutral . . . It may turn out that earthing the screen is a retrograde step. 

Would that be better than the ADSLNation plate I currently have? openreach fitted their own faceplate (not sure if it was a mk1 or 2) after breaking the NT-5 trying to get the ADSLNation plate off by brute force (stripped screw on one side)

Was it a true Openreach technician (engineer) rather than a sub-contractor numpty? If the SSFP is not marked Mk 2 in the top right-hand corner, then it is a Mk 1! So if I understand correctly, at the time of your FTTC installation, a new NTE5/A and a SSFP were fitted?

Just something to think about -- the ADSLNation centralised filter was designed for use with ADSL2+ (or ADSL2 or G.Dmt) and not VDSL2. When FTTC was first launched, it was only Profile 8. Now it is Profile 17. The ADSLNation filter is, quite probably, being used at frequencies outside of its design specification. It might be worth testing with the Openreach provided SSFP. 

As for your FEC graph, I see kitz has explained that it should be considered along with the CRC graph and not in isolation.

[loonylion]

IIRC it was an openreach engineer, unless she'd stolen an openreach van and uniform from somewhere She had test kit too, which, from what I gather reading this forum, cowboy contractors don't have.

The ADSLNation faceplate wouldn't come off because of a stripped screw, so she wrenched it and broke the NT-5, which she replaced, and she cut the wires off of the (old) NT-5 too short and then had to crimp new ones on, although there was plenty of slack in the cable so she could just have pulled more out from the wall (I do wonder if that crimped connection could be affecting the signal at all). She made no comment about it being 4 pair foil shielded cable :p

I'll have to find the OR SSFP to see which variant it is.

[Black Sheep]

I concur with B*Cat. I think your Dad has taken a backward step by removing the OR fitted plate, in favour of the ADSL Nation. I suppose the clue is in the brand-name ....... ADSL - 'up to 2.2Mhz'. Whereas VDSL uses up to 4 different band-plans over a lot higher frequencies.

As The cat has pointed out, if you re-fit the OR plate, and it is hopefully a MK2, then it may filter out some of the incrementing FEC's you are currently seeing ??

Edited to add ...................... none of our cables are 'shielded'.

[loonylion]

and a new error/seconds graph, this was mostly while I was asleep so very little using the connection.



CRCs much the same as described before, FEC still looks like a mountain range. Going to look for the OR SSFP today, Should I be considering flashing the modem to the experiemental firmware in HW's thread at some point?

[les-70]

  I have not been following this but have taken a quick look from the start of the post.  My impression is that your QLN is fine, generally -140db seems to be a typical "mush" floor  on a longer length line which it is hard do a lot better than.  The attenuation matches a longer line giving the moderate rate sync, I assume that reflects your distance from the CAB.  The extent of peaks in the QLN also looks quite normal.  As you pointed out its the error rates which seem a bother and must have resulted in the interleaving and speed cap.  It may be that the errors are due to REIN i.e. odd spikes of noise that may not show up in the stats very often or very well?

 I was getting about 25 errored secs per hour but with the changes I made I have reduced that to about 5-8 per hour (on fast path).  Bcat gave a link to my tests to achieve that.   In my case, I have to say, it took a lot of trouble and several disconnects per day for a few weeks to achieve all the tests reliably. Thats fine if like me you find it interesting but it would not suit those less curious.  Bcat also mentions an RF3,  I tried that  http://forum.kitz.co.uk/index.php?topic=13420.msg259441#msg259441 but did not leave it in to see what influence it had on errors.  It would have cost me the price of a 17Mb/s drop in attainable!.  (I am curious as to exactly what BT means by getting RF3 performance in the SSFP in the future).  In your case with no use of the higher frequencies I would guess a drop in attainable of much less, perhaps a few Mb/s or less.  If it reduced the errors enough it might give a net benefit.

 (I have been hoping that roseway -eric might produce a version of dslstats with the option to stayed logged in and allow much higher frequency sampling, that might pick up such spikes. I used to notice them better in "dmt" with 2 second sampling but dmt is not an option with vdsl.)

[NewtronStar]

Loonylion I think you have the same type of FFTC line as me with stong RFI, I purchased the MKII faceplate and Installed this made no difference to RFI and your FEC's errors counts are ok (well within normal working parameters) a bad continuous FEC count to me would be 100000 + per min

Now your last Graph is showing to be in sync for two days, I would delay any testing/experiments for 14 days with (Modem on 24/7) and if no change then get the Krone Tool in the ready position.

[loonylion]

another update.

Modem uptime is now 14 days 22 hours, DSL uptime 1 day 7 hours. Sync speed is up to 34999kbps with interleave of 1123 and INP of 3.50, ES/h of 5.99.

Upstream ES/h is 7.59

[Chrysalis]

The adslnation plate I had many years ago was bad on adsl never mind FTTC, a x2e dongle I had (if I remember name right) did much better job. but when I tested that dongle on FTTC it was no better than the openreach faceplate, and since it wasnt rated for FTTC I didnt keep ti in use other than the test.

Stick with a MK1 or MK2 FTTC plate.

[NewtronStar]

another update.

Modem uptime is now 14 days 22 hours, DSL uptime 1 day 7 hours. Sync speed is up to 34999kbps with interleave of 1123 and INP of 3.50, ES/h of 5.99.

Upstream ES/h is 7.59

Good the Sync speed is going up but your Interleave has not dropped very much since your last stats I think it was 1200 so now it's 1100 give it another week and keep the BT Modem on 24/7 and let us know if your getting any disconnection. 

[loonylion]

And another update.

I haven't changed anything, but the modem resynced again a couple of days ago, and DS is now reporting 39999kbps in dslstats, with an attainable of 48468. SNR margin on D1 is 6.8dB with attenuation of 18.8dB, and on D2 6.9dB with 51dB attenuation. Interleave is still 1173 with INP of 3.0

ES/hour is 5.23 with 541 ES and 7 SES in 2 days 10 hours 48 minutes DSL uptime.

I'm happy with the speed (though won't say no if I can get more ) but I'd like to get the ES down a bit. Will try the mk2 sffp.