Kitz Forum

Broadband Related => Telephony Wiring + Equipment => Topic started by: burakkucat on September 03, 2014, 04:10:42 PM

Title: SSFP Mk 3
Post by: burakkucat on September 03, 2014, 04:10:42 PM
As predicted a few months ago, the Mark 3 Service Specific Face Plate has now been released and limited quantities have appeared at a certain on-line auction site.

An example (http://www.ebay.co.uk/itm/BT-Openreach-VDSL-Faceplate-MARK-3-JUST-RELEASED-Sealed-Brand-New-Genuine-/251635637181).
Title: Re: SSFP Mk 3
Post by: roseway on September 03, 2014, 04:52:40 PM
Thanks for the heads up. I now have one on order.
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 03, 2014, 04:57:59 PM
Ha ha ...... how ridiculous is it that you know before I do, of their availability ?? Madness.

Cheers for the heads-up, B*Cat. Now get your scientific, reverse-engineering head on and let us know what the hell is different please.  :graduate: ;D
Title: Re: SSFP Mk 3
Post by: burakkucat on September 03, 2014, 05:22:44 PM
I was hoping that somebody such as fellow Kitizen JGO (http://forum.kitz.co.uk/index.php?action=profile;u=6929) will be able to explain the differences between the Mk 2 and the Mk 3!  :D
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 03, 2014, 10:27:02 PM
O_o

cant find any, anyone got a url?
Title: Re: SSFP Mk 3
Post by: burakkucat on September 03, 2014, 10:36:21 PM
Have you tried left-clicking upon "An example (http://www.ebay.co.uk/itm/BT-Openreach-VDSL-Faceplate-MARK-3-JUST-RELEASED-Sealed-Brand-New-Genuine-/251635637181)" in my original post?  :-\
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 03, 2014, 10:50:45 PM
with my experience with SSFP MKII and BT80b RF3 it's going to need a 100% improvement over it's predecessors for any BroadBand DIYer to buy this product.

Again you will see the placebo effect with a few users saying it's the best thing since sliced bread and then you will see the majority of users saying it makes no difference  ;)
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 03, 2014, 11:00:58 PM
Have you tried left-clicking upon "An example (http://www.ebay.co.uk/itm/BT-Openreach-VDSL-Faceplate-MARK-3-JUST-RELEASED-Sealed-Brand-New-Genuine-/251635637181)" in my original post?  :-\

ok thanks bud.
Title: Re: SSFP Mk 3
Post by: roseway on September 06, 2014, 03:48:37 PM
Mine turned up today, and I fitted it in place of the Mk 2 this afternoon. I can't really say that there's any significant difference (this is on an ADSL2+ connection). I presume its main intent is to improve VDSL2 connections, so I can't measure it against its real purpose.
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 06, 2014, 04:57:59 PM
mine came today also, but I have left it wrapped as I have a line fault currently.

Do we have them before black sheep?
Title: Re: SSFP Mk 3
Post by: roseway on September 06, 2014, 06:27:06 PM
Looks like it :)
Title: Re: SSFP Mk 3
Post by: boost on September 06, 2014, 06:32:21 PM
Eagerly awaiting someone to pull one apart and say great things about it :)
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 06, 2014, 09:46:37 PM
Mine turned up today, and I fitted it in place of the Mk 2 this afternoon. I can't really say that there's any significant difference (this is on an ADSL2+ connection). I presume its main intent is to improve VDSL2 connections, so I can't measure it against its real purpose.

Well the SSFP MK2 was supposed to work for both ADSL and VDSL2 it would seem the SSFP MK3 is also the same, I am trying my best not to be pessimistic here but having a cubpoard filling up with these device's that don't make any difference to the line stats is becoming the norm here.
Title: Re: SSFP Mk 3
Post by: neilius on September 06, 2014, 09:50:44 PM
Ordered. If nobody else dissects it by the time it arrives, I'll have a poke about and compare its guts to a Mk2. ;D
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 06, 2014, 10:30:03 PM
Ordered. If nobody else dissects it by the time it arrives, I'll have a poke about and compare its guts to a Mk2. ;D

You do that and hope you will post back on how the line stats compare SSFP MKII vs MKIII i am not so much interested in the components used on the circuit board it's more does it make any difference to your broadband  ;)
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 07, 2014, 10:43:11 AM
mine came today also, but I have left it wrapped as I have a line fault currently.

Do we have them before black sheep?

Not only do you have them before us, to all intents and purposes, we are unawares they even exist !! There has been no communication at all that the MK3 is service-ready and available. You have to bear in mind, we are a communications company.  ;) ;D
Title: Re: SSFP Mk 3
Post by: les-70 on September 07, 2014, 02:51:38 PM
  A me too!.  I put the mark 3 in place late this morning.  It is too early to give any reliable performance indications, just first impressions. The attainable  and sync speed went up roughly 1 Mb/s and the error rates seem about 30% lower.  This could just be a lucky time of day change so I will report on long term results in day or so.

 I attach the snr/per tone graph just before and after the swap. With the mark 3 the highest frequencies are less attenuated and carry more bits.

The graphs are with the line capped at 64 Mb/s (which can be judged in relation to the lowest recent attainable speed of 73mb/s).  At the time the reported attainable was 76 with an HG612- first swapped to a Billion 8800NL (with latest firmware) which gave 78 and then the with the billion and mark 3 - 79  :) .  Note that line conditions may have changed during the swap and as noted above a longer test is needed for a live connection.

 
Title: Re: SSFP Mk 3
Post by: burakkucat on September 07, 2014, 05:47:06 PM
In his rush to try to do too much in too short a time yesterday, b*cat forgot to mention that his Mk 3 SSFP also arrived on Saturday. Damaged in the post.  :rain:

The supplier was very quick to acknowledge my (eBay) message (complete with photographs), apologised for the mishap and promised to dispatch a replacement to The Cattery on Monday.  :)

If he does not want me to return the broken one, I will take the PCB out of the case and photograph it alongside a Mk 2 SSFP PCB.  ;)
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 07, 2014, 06:31:56 PM
My gut tells me that most members are more interested in looking whats inside the MKIII than actually testing weather it can deliver the goods on what's it's supposed to do.

I wanna see long term graphs (1 month) to see if it works or fails to deliver  ;D
Title: Re: SSFP Mk 3
Post by: les-70 on September 07, 2014, 07:21:00 PM
  A long term graph would only show the state of the connection and most likely some change with time as other lines get services.  A true test would involve comparisons under fixed but realistic conditions.    In the absence of test conditions i tend to rely looking for consistency of changes with swaps in and out. That is how I have evaluated modems and other components.  I will try to alternate the mark 3  with a mark 2 a few times over the next week or two to see if differences seem consistent each time.  Today shows a hopeful gain from one insertion.  If that gain is true I expect a loss on going back to the mark 2 and a repeat gain on returning to the mark 3.  Long term is only correct in the sense that enough time is needed each time to ensure varying situations  are coped with. 
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 07, 2014, 09:40:13 PM
Long term is only correct in the sense that enough time is needed each time to ensure varying situations  are coped with.

Yeah les-70 I like your thinking and another way to judge the difference for each device over time is looking to see the how the error averages look in dslstats 7 days with MKIII and 7 days with MKII that should be a good realistic test  ;)
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 07, 2014, 10:09:36 PM
Not only do you have them before us, to all intents and purposes, we are unawares they even exist !! There has been no communication at all that the MK3 is service-ready and available. You have to bear in mind, we are a communications company.  ;) ;D

If thats the case BS someone is being fraudulent and just changing the logo of the MK2 to MK3 and putting them on fleebay hope thats not the case, now I can unterstand why members need to have a look at the PCB  :-X
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 08, 2014, 07:17:01 AM
Hmm ..... I hadn't thought of that angle ??

TBH, my own thoughts are that they will probably be the genuine article, they just wont have gotten round to let the engineers aware of their availability ?? It's happened before, you wont be surprised to hear!!
Title: Re: SSFP Mk 3
Post by: roseway on September 08, 2014, 08:05:10 AM
For reference, here are pictures of the inside of an SSFP Mk2:

(http://photos3.pix.ie/0A/22/0A225A11764943B8BD3643C16D515C9A-0000349545-0003659898-00800L-00E462DEA1BE47848EFF3C865ACBCEC6.jpg) (http://pix.ie/oldgrump/3659898)

(http://photos3.pix.ie/B1/28/B128F71A7BBA433495EE79F5D89693BF-0000349545-0003659897-00800L-2FD702053FD541428B1879301DADA2DE.jpg) (http://pix.ie/oldgrump/3659897)
Title: Re: SSFP Mk 3
Post by: les-70 on September 08, 2014, 11:08:20 AM
 Unfortunately my master socket is behind a heavy cupboard which needs emptying to move it.  I have now had severe complaints   :(  re leaving the cupboard away from the wall, the room full of the contents, and possibly marking the carpet.  I have therefore done another swap test before putting it all back with the mark 3. I won't be swapping as much as I planned to.

I just briefly went  back to the mark 2 and then returned to the mark 3.  The attainable increase of about 1 Mb/s with the mark 3 occurred again so I am tending to believe it.  :) Judging from the previously posts bit loading's this improvement may only occur if your attainable is above about 60Mb/s and your using the highest frequency 17a tones.

The error rate over 24 hours with the mark 3 continued,  from a couple of hours, to be about 30% less than the smallest normal 24 hour average, but as suggested by NewtronStar, I am sure a longer test is needed to judge error rates.  I will now do a 7 day test with the Billion and then one with an HG612 as I am used to the error rates with both of those so a rough evaluation may be possible if thunderstorms allow!
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 08, 2014, 03:22:36 PM
personally I think these are genuine, just some guy who got access to stock or whatever selling a bunch off :)
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 08, 2014, 11:11:08 PM
personally I think these are genuine, just some guy who got access to stock or whatever selling a bunch off :)

Its Just me being paranoid again CHRY if the MK3 is able to reduce the errors by say 8% then I'll puchase one, but my findings our if the user has a low to medium exisiting HR fault then the MK2 or 3 will not help to much.

I will now do a 7 day test with the Billion and then one with an HG612 as I am used to the error rates with both of those so a rough evaluation may be possible if thunderstorms allow!

Even in our home for example a pull cord switch for the light in the bathroom looks like a T/Strike on my line stats 20 to 25 CRC's it only happens when its pulled to the on position never to the off position.

I guess in most UK homes there will always be mains switch arcing, Can't see the MK3 being any different than the MK2 when it incounters mains switch arcing unless your home is a new build.

I think most CRC and ES errors come from inside the EU premises via the 240 mains supply, so my thinking you would be better of with an expensive mains Conditioning Filter to your Modem and Router.
Title: Re: SSFP Mk 3
Post by: les-70 on September 09, 2014, 07:05:08 PM
   I managed to get a stay of execution of one day prior to fully putting the cupboard back.  I also try to never have more than 3 re-syncs per day when testing as that does not seem to have ever upset the DLM.  I therefore decided to use the resyncs on a HG612 instead of the Billion for 24 hours. The mark 3 gave a smaller speed increase with the HG612 of about 0.5 Mb/s and over 24 hours errors were about 20% less than the usual good day average.  I would need to repeat this a few times to be fully convinced but it looks hopeful. 

  On its own the Billion 8800NL with the latest 039 dsl driver firmware seems to make better use of the higher frequencies and as the mark 3 seemed to have less attenuation at the highest frequencies it may be a favorable combination.  This may be consistent with switching back to the Billion with the mark 3 place giving an attainable increase of 3.5Mb/s c.f the HG612 (which may or may not be significant). A just under 3Mb/s increase was previously seen with the mark 2. 

  I have now definitely started a long test with the Billion.
Title: Re: SSFP Mk 3
Post by: oddlegs on September 10, 2014, 10:27:51 AM
I note that the SSFP Mk2 faceplate has been apparently replaced by the Mk3, but does anyone know what was supposed to be wrong with the Mk2 ?
I am on an EO line of around 3.5 km with a longish drop wire located the best part of 1000 feet above sea level on the top of a hill.
I have always suffered from a large variation in day/night noise margin. This meant that my line would lose sync at regular intervals.
I partially got around this with the excellent Billion 7800n with altered default noise margin and the Phyr option but my usable sync peaked at around 7000 kb/s.
About 2 months ago I replaced my V10 faceplate with a Mk2 and the difference was amazing. My sync is now well above 8000 kb/s and the noise margin hardly drops at all overnight. Speed tests are above 7200 kb/s.
I have been connected now without sync drops for several weeks.
Strangely enough, some time ago I tried a RF3 filter in the modem adsl lead and that made things much worse rather than better.
If the only difference with the Mk2 over the older faceplate is the integrated RF3 common mode choke why did it not work before ?
I shall stick with the Mk2 for now I think.
Title: Re: SSFP Mk 3
Post by: roseway on September 10, 2014, 10:39:14 AM
I don't know the answer to your question, but I think it's most probable that the difference between the Mk 2 and Mk 3 is only in the higher VDSL2 frequencies. There was no recognisable difference when I made the change on my current ADSL2+ connection.
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 10, 2014, 11:55:27 AM
I probably wont be using my mk3 unless a new line problem manifests itself sorry guys.
Title: Re: SSFP Mk 3
Post by: Ronski on September 10, 2014, 06:39:49 PM
I ordered one last night, so I shall see what difference it makes to my line when it arrives.
Title: Re: SSFP Mk 3
Post by: burakkucat on September 11, 2014, 05:27:42 PM
The replacement Mk3 SSFP arrived this morning and so the damaged one was opened up and its PCB was photographed. The image is attached below, along with that of a Mk2 SSFP's PCB.

It's let us play "spot the difference" time.  ::)
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 11, 2014, 05:58:39 PM
also those four small tube type things at top are different colour
Title: Re: SSFP Mk 3
Post by: HPsauce on September 11, 2014, 06:01:51 PM
Resistors.  ;)
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 11, 2014, 06:07:38 PM
Looks like it has more windings on the ferrite core on the MK3
Title: Re: SSFP Mk 3
Post by: burakkucat on September 11, 2014, 06:20:03 PM
also those four small tube type things at top are different colour

Although the body colours are different, the bands (http://en.wikipedia.org/wiki/Electronic_color_code) designating the resistance are the same. (I see red, black, black, gold which shows them as 20 Ohm +/- 5%)
Title: Re: SSFP Mk 3
Post by: burakkucat on September 11, 2014, 06:24:06 PM
Looks like it has more windings on the ferrite core on the MK3

Yes, indeed. The two windings on that toroid are in series with the A & B wires of the circuit, immediately following the plug which connects to the NTE5/A.
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 11, 2014, 06:44:22 PM
Looks like it has more windings on the ferrite core on the MK3

Yes, indeed. The two windings on that toroid are in series with the A & B wires of the circuit, immediately following the plug which connects to the NTE5/A.

Thats going to add a bit more attenuation to the line not by that much say 1.0 to 1.5 dB but suspect it will be higher than the MK2 which added 0.5dB to the attenuation :-\
Title: Re: SSFP Mk 3
Post by: les-70 on September 11, 2014, 07:02:59 PM
When swapping between the mark 2 and mark 3 on an Hg612 there was no change in my over all attention or sync. pbParams showed no changes in D1 and D2 and a consistent 0.4 db increase in D3.  in U1,U2 and U3 there were some 0.1 db increases in some values but nothing significant.  With the HG612 there was nothing really significant at all.  A 1 day test suggested a smaller error rate reduction but my error rates are not really stable enough to allow a reliable judgment.
Title: Re: SSFP Mk 3
Post by: Semmy on September 11, 2014, 07:09:18 PM
The guys at BT Harrogate are aware of the issue (as in issuing out of the stores) of the Mk3 SSFP so it is definitely legit item.

(edited for clarity)
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 11, 2014, 07:52:22 PM
What the issue, Semmy ??
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 11, 2014, 08:23:49 PM
so MK4 incoming?
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 11, 2014, 08:36:53 PM
 :lol:
Title: Re: SSFP Mk 3
Post by: burakkucat on September 11, 2014, 09:07:48 PM
The guys at BT Harrogate are aware of tge issue of the Mk3 SSFP so it is definitely legit issue.

Me thinks that you intended to paw out "issue of the Mk2 SSFP", as that is the device of which the Wizards of Grimbledon Down1 were tasked to "look again". The Wizards looked, changes were made and the Mk3 SSFP is the result.

Of course the Mk3 could, in turn, be lacking!  ::)

1Adastral Park
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 11, 2014, 09:18:24 PM
Think it's not a band job as on the ferrite ring (toroid) the A & B windings look as if they have been insulated from each wind on the core, would need a close up with the camera using macro mode to see the fine detail.

& thanks B*CAT for taking the time to expose the difference between the two devices  :thumbs:
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 11, 2014, 09:24:48 PM
Concur, thanks for posting up the MK3, cat. Albeit rather a let-down ...... I wanted to see a warp-drive in there, or at least some dilithium crystals ??  ;) 
Title: Re: SSFP Mk 3
Post by: burakkucat on September 11, 2014, 09:39:08 PM
I may be wrong but I suspect that is a bifilar winding (http://en.wikipedia.org/wiki/Bifilar_coil) on the torid.  :-\

If we think back to JGO's description of the mode of operation of an RF3 (http://forum.kitz.co.uk/index.php?topic=13473.0) -- it rejects common-mode signals but passes differential-mode signals -- then the purpose of that torrid comes into focus.

Before anyone asks, the other side of each of the PCBs (the "wiring" tracks) are identical.
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 11, 2014, 10:11:02 PM
I may be wrong but I suspect that is a bifilar winding (http://en.wikipedia.org/wiki/Bifilar_coil) on the torid.  :-\

If we think back to JGO's description of the mode of operation of an RF3 (http://forum.kitz.co.uk/index.php?topic=13473.0) -- it rejects common-mode signals but passes differential-mode signals -- then the purpose of that torrid comes into focus.

Before anyone asks, the other side of each of the PCBs (the "wiring" tracks) are identical.

Thats what the MK2 was supposed to do, but it does seem the windings on the MK2 where not rejecting the common-mode enough.

OK I am going to purchase one tomorrow if there is any left, though I am sure my line needs an Openreach Engineer with a JDSU to hand to make the MK3 work as intended.

As I have said in the past you won't know for certain until you try it out for yourself that's the best test around  :)
Title: Re: SSFP Mk 3
Post by: kitz on September 12, 2014, 01:44:09 AM
Thank you black cat for posting those images :)
Title: Re: SSFP Mk 3
Post by: Black Sheep on September 12, 2014, 07:27:01 AM
Am visiting our 'Stores' today, shall see if they are available to us ??
Title: Re: SSFP Mk 3
Post by: les-70 on September 12, 2014, 01:10:29 PM
  I have abandoned testing the mark 3 due to another increase in cross-talk taking away the relevance of any new results c.f. the results to date.   I have 5 days of results prior to this change 2 days  with a Hg612 and 3 days  with a Billion 8800NL.  I also have in/out results twice for each modem. 

   Conclusion  HG612  --  nothing really significant - no sync speed impact - a tiny increase in attention of highest tones +0.4 in D3. Maybe a small error rate reduction.

  Conclusion 8800NL  -- A small increase in sync speed ~0.5 Mb/s - consistent with a improvement in D3 snrm.  Maybe a small error rate reduction.

  Nothing worth a fuss over.  I guess the difference in response between the HG612 and 8800NL maybe the internal circuits or the different chipsets and dsl drivers.

  Although the 8800NL gave a higher sync, by 3.5Mb/s, it also gave at least twice the error rate of the HG612.  An error rate difference also persisted with the sync speeds of both devices capped so to be identical!  In spite of a higher SNRM the 8800NL then still had about 40% greater error rates, with either the mark 3 or mark 2.  Maybe a bit less with the mark 3.

  I am leaving the Mark 3 in place if only for the reason that it is a bother to change it.

 

Title: Re: SSFP Mk 3
Post by: Jasonkruys on September 12, 2014, 04:55:51 PM
The guys at BT Harrogate are aware of tge issue of the Mk3 SSFP so it is definitely legit issue.

Me thinks that you intended to paw out "issue of the Mk2 SSFP", as that is the device of which the Wizards of Grimbledon Down1 were tasked to "look again". The Wizards looked, changes were made and the Mk3 SSFP is the result.

Of course the Mk3 could, in turn, be lacking!  ::)

1Adastral Park

I think what was actually meant was "know about the release (issue/availability/sending out of/ insert preferred word here). Not that there is AN issue 😊
Title: Re: SSFP Mk 3
Post by: Semmy on September 12, 2014, 08:49:08 PM
Yup! Unfortunately I was posting from a mobile device and made a pigs ear of the post!
Title: Re: SSFP Mk 3
Post by: Ronski on September 13, 2014, 01:00:27 PM
Fitted my Mk3 today at 12:30, my stats can be seen on MyDSLWebstats, slight increase in down sync and a drop in up, but then the attainable was lower on the up so that was expected.
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 13, 2014, 09:42:49 PM
Have not yet purchased the MK3 as of yet as I am 99.4% sure it's not going to cure my RFI issues in the evening, having said that I did install the BT80b RF3 back inplace last night to make some kind of judgement for the next evening RFI (to-day)

Yes the SNR at the higher tones have increased from 6dB to 12dB
And No the higher tones effected by the RFI still disappear in a large chunk with no Bits or SNR
used during the hours close to sunset and after.
Yes the errored seconds have gone down from 8.8 ES/hour to 0.92 using dslstats this may change the next day as it needs to see 24 hours worth to get an average.

Do I expect a miracle from the MK3 to fix this by the revised ferrite ring of course not  :D

Title: Re: SSFP Mk 3
Post by: les-70 on September 14, 2014, 09:28:47 AM
Yes the SNR at the higher tones have increased from 6dB to 12dB
And No the higher tones effected by the RFI still disappear in a large chunk with no Bits or SNR
used during the hours close to sunset and after.
Yes the errored seconds have gone down from 8.8 ES/hour to 0.92 using dslstats this may change the next day as it needs to see 24 hours worth to get an average.

   That is a dramatic improvement especially in the errored seconds.  Assuming it is real over 24hours, I would be using an RF3 if it gave just a bit of that impact. I found not much impact on errors, just a big drop in attainable!.  I guess I may have the wrong sort of errors.
Title: Re: SSFP Mk 3
Post by: neilius on September 14, 2014, 10:26:44 AM
Here's a macro shot of the new toroid for detailed perusal. :)
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 14, 2014, 01:10:57 PM
under 1 ES/hour is excellent. if you maintain that average.

Title: Re: SSFP Mk 3
Post by: NewtronStar on September 14, 2014, 04:29:33 PM
Here's a macro shot of the new toroid for detailed perusal. :)

Thankyou very much neilius that's precisely the picture I was hoping to see, a lot more A & B windings on the toroid and also well insulated from each other.

under 1 ES/hour is excellent. if you maintain that average.

It has gone up to 10.3 ES/hour my average over 24 hours is 182 down and 46 up, It would be nice to experience fastpath on the DS the US is always using fastpath, if the MK3 could stop the attainable (max rate) fluctuating so much then I am sure the DS SNRM would become steady and that should result in lower errors.

MR BT80B RF3 in place and waiting for it's mate FFSP MK3  ;)
Title: Re: SSFP Mk 3
Post by: neilius on September 14, 2014, 04:51:49 PM
Quote from: NewtronStar
Thankyou very much neilius that's precisely the picture I was hoping to see, a lot more A & B windings on the toroid and also well insulated from each other.

No problem. Looks like enamelled wire and then the whole lot is covered in epoxy.
Title: Re: SSFP Mk 3
Post by: burakkucat on September 14, 2014, 06:45:50 PM
Quote
I may be wrong but I suspect that is a bifilar winding (http://en.wikipedia.org/wiki/Bifilar_coil) on the torid.  :-\

I was, most definitely, wrong.  :-[
Title: Re: SSFP Mk 3
Post by: Chrysalis on September 14, 2014, 06:47:21 PM
182 per 24 hours is good also, however that 182 is whilst you are interleaved which perhaps makes it not so good.

you can do what les does and raise the target snrm, try setting it to 8db.
Title: Re: SSFP Mk 3
Post by: pooclah on September 24, 2014, 05:28:06 PM
Hi all

Attached are QLN graphs from a few hours before and immediately after I replaced a SSFP MKI with a MKIII.  Any ideas to why a bit of the ‘after’ graph is missing?

Hopefully this hasn’t been answered somewhere and I’ve missed it.
Title: Re: SSFP Mk 3
Post by: burakkucat on September 24, 2014, 05:51:21 PM
Welcome to the Kitz forum, poo.  :)

As the "missing" segment is from the US portion of the graph I would not be too concerned about it. However you could take a look at the raw data that was used to plot the "after" graph and compare it with that for the "before" graph.

It really depends . . . some people, like myself, never see the US portion of the graphs whilst other people will always see it.
Title: Re: SSFP Mk 3
Post by: pooclah on September 24, 2014, 06:20:24 PM
Hi BK

Thanks for the welcome & the reply

I just thought it was odd that a portion of the graph disappeared after replacing the face plate when it was always there before, but never after.

I'll take a look at the logs but unless something jumps out at me I'm not too sure what I'm looking for.
Title: Re: SSFP Mk 3
Post by: Bald_Eagle1 on September 24, 2014, 06:29:31 PM
I would suggest that you compare US Attainable rate (MAX) & sync speed (Path or Bearer) from before & after the swap.

These are my current stats (Mk2 SSFP):-

Max:   Upstream rate = 4121 Kbps, Downstream rate = 21244 Kbps
Bearer:   0, Upstream rate = 4055 Kbps, Downstream rate = 21247 Kbps

They didn't change much at all when I switched from the Mk1 to the Mk2 faceplate.



Also, you could look at Hlog, SNR & Bitloading graphs to see if previously usable tones are now unusable.


To confirm if the different SSFPs do affect performance etc., you could try swapping back to the Mk1 SSFP to see if the missing data returns & then back to the Mk3 SSFP to see if they disaappear & affect other stats again.



Title: Re: SSFP Mk 3
Post by: pooclah on September 24, 2014, 06:56:19 PM
Hi BE

I see where you guys are coming from now.

I’ll swap the face plates tomorrow (too many bods in the house using t’internet at the moment) plus the DLM is watching me, which was the reasoning behind the MK3 faceplate.

If there's anything that doesn't make sense to me I’ll post the results tomorrow in a new thread for you guys with a better understanding to look at, rather than drag this one off course because as I said the MK3 was to try and solve issues

Regards Kevin
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 24, 2014, 10:56:30 PM
rather than drag this one off course because as I said the MK3 was to try and solve issues
Regards Kevin

I think BE1 will agree with me on this one, not one line is identical so it may work better for some and less for others I know it's annoying but it's true, you have just got to try the different configs MK1 MK2 and MK3 to see which one's work's best for you.

What were the issues your having that made you purchase the MK3 to solve it ?
Title: Re: SSFP Mk 3
Post by: pooclah on September 25, 2014, 06:19:20 PM
Hi NS

I understand that all lines are different but I was just curious as to why there was no gap in any graph pre the MK3 face plate but present in every graph after fitting it.

The reason for getting the MK3 was to see if it help with the sudden onslaught of errors that hit my connection.

I’ve just got in from work and have a house full of grandchildren, or it seems like it, they’re everywhere, so I probably won’t be swapping the face plates tonight. 

I had a resynch during the night (retrain reason 1?) and some of the missing line in the graph came back.
Title: Re: SSFP Mk 3
Post by: pettaw on September 25, 2014, 10:02:13 PM
For me, the MK3 has been a downgrade. I put the Mk3 on 2 days ago and I have lost approx 2Mb/s sync speed and about 1Mb/s download throughput speed. My line normally syncs at about 64000 and my sync after fitting the MK3 was about 62300. Upload speed also dropped from max of 19999 to about 18400.
I don't log my connection but I am one of the Samknows 'white box' testers who has a special router on my connection so having switched back this evening I will hopefully see my speeds increase back to where it was before I switched.
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 25, 2014, 11:21:03 PM
For me, the MK3 has been a downgrade. I put the Mk3 on 2 days ago and I have lost approx 2Mb/s sync speed and about 1Mb/s download throughput speed. My line normally syncs at about 64000 and my sync after fitting the MK3 was about 62300. Upload speed also dropped from max of 19999 to about 18400.

Yes pettaw but a loss of 2Mb/s US line sync and loss of 1Mb/s DS line sync could be because you rebooted the Modem while the Attainable Line rate was at it's lowest point.

I do try when testing RF3's and MK2 to match the same Attainable line rate after inserting each device's in place and power up the modem, this way it stop's you getting conflicting line sync's when testing those devices.
Title: Re: SSFP Mk 3
Post by: les-70 on September 26, 2014, 06:44:58 PM
  Ever since FTTC was installed I left the mark 2 SSFP in place until swaping it for the mark 3.  I just did the test of adding back the mark2 in series with the Mark3.    The test suggests the the mark 2 and probably both faceplates may be losing  ~3Mb/s of sync c.f the master socket.  Tests are with the HG612 capped at 72Mb/s

Mark 3 on its own
Max:   Upstream rate = 23680 Kbps, Downstream rate = 78260 Kbps
Bearer:   0, Upstream rate = 20000 Kbps, Downstream rate = 72030 Kbps
      Down      Up
SNR (dB):    8.0       6.6
Attn(dB):    17.5       0.0
Pwr(dBm):    13.3       5.1

Mark 3 +2

Max:   Upstream rate = 23460 Kbps, Downstream rate = 74888 Kbps
Bearer:   0, Upstream rate = 20000 Kbps, Downstream rate = 72030 Kbps
SNR (dB):    7.2       6.5
Attn(dB):    17.6       0.0
Pwr(dBm):    13.3       5.2

 Given that the old Pressac adsl faceplate was straight through for the adsl signal I wonder whether it worth trying that again.  I guess the drop in attainable is due to the Rf3 part of the face plate and wonder whether the loss of 3 Mb/s is worth the benefit of that gives?
Title: Re: SSFP Mk 3
Post by: burakkucat on September 26, 2014, 08:17:15 PM
I just did the test of adding back the mark2 in series with the Mark3.

 ???  I just can't see that. No matter how I try, it doesn't make sense to have a NTE5/A with a Mk 3 SSFP and a Mk 2 SSFP "on top". The socket, into which the Mk 2 SSFP is plugged, is via the LPF in the Mk 3 SSFP. So from where are you taking the xDSL signal to feed to the modem/router?
Title: Re: SSFP Mk 3
Post by: les-70 on September 26, 2014, 09:09:03 PM
  Sorry for not being clear but I was about to go out of the house.  I have taken the adsl/vdsl output of an installed Mark 3 into the input of a second NTE5 with the Mark 2 SSFP attached to that and then the Mark 2 to the Hg612.  It is two master sockets and their respective SSFP face plates in series.  I might have done a master socket test instead but that would have involved emptying a cupboard and moving it!  In a previous post I noted no difference in sync between the Mark 2 and 3.
Title: Re: SSFP Mk 3
Post by: burakkucat on September 26, 2014, 09:49:56 PM
Ah, I see. Thank you.  :)
Title: Re: SSFP Mk 3
Post by: les-70 on September 27, 2014, 06:57:51 PM
  I said I would compare the Mark3 with the BT NTE-2005 ADSl v1.0 faceplate made by Pressac.  The NTE-2005 has from my looking a the circuit no "RF3" type component and connector A and B from the drop wire go straight to the adsl line. 

 Here are the Mark 3 stats.

Max:   Upstream rate = 23663 Kbps, Downstream rate = 77788 Kbps
Bearer:   0, Upstream rate = 20000 Kbps, Downstream rate = 72030 Kbps
      Down      Up
SNR (dB):    7.9       6.6
Attn(dB):    17.5       0.0
Pwr(dBm):    13.3       5.1

  Here are the NTE-2005 stats

Max:   Upstream rate = 23936 Kbps, Downstream rate = 79268 Kbps
Bearer:   0, Upstream rate = 20000 Kbps, Downstream rate = 72030 Kbps
      Down      Up
SNR (dB):    8.3       6.7
Attn(dB):    17.5       0.0
Pwr(dBm):    13.3       4.9

  With the absence of the "RF3" type component I was expecting a higher attainable and indeed it is 1.5 Mb/s higher  :). My previous impression was that the Mark 2 had a more aggressive "RF3" than the Mark 3 so I guess that a Mark 2 to NTE-2005 swap should show a slightly bigger improvement. I attach the respective snrm and bitloadings per tone.    After 45 mins the error rates (with the speed capped) look less  :)  but a reliable error rate test will take a few days to do properly.

 Very Tentative conclusion 

 Both the Mark 2 and Mark 3 may have common mode filtering that has a negative impact impact on some (possibly many) lines.  Almost all modems are pretty good at rejecting common mode and I have long wondered why BT thought they could do better.  The RF2/3 may have had a purpose when people could hear radio channels on their phone calls but the adsl/vdsl filter in a face plate should stop RF on the drop wires reaching the phone (I think!).



Title: Re: SSFP Mk 3
Post by: NewtronStar on September 27, 2014, 11:10:23 PM
but a reliable error rate test will take a few days to do properly.

I would not expect the MK2 or MK3 to increase your broadband rate if your error rates are low, the only thing they can do is to "try" and lower thoses errors 24/7, I am going to tell you those devices are useless to combat against external RFI (radio frequency interference) , but they do seem to fair better with internal EMI (Electromagnetic interference).
Title: Re: SSFP Mk 3
Post by: JGO on September 28, 2014, 08:03:40 AM
Very Tentative conclusion 

 Both the Mark 2 and Mark 3 may have common mode filtering that has a negative impact impact on some (possibly many) lines.  Almost all modems are pretty good at rejecting common mode and I have long wondered why BT thought they could do better.  The RF2/3 may have had a purpose when people could hear radio channels on their phone calls but the adsl/vdsl filter in a face plate should stop RF on the drop wires reaching the phone (I think!).

It needs figures from many caes !
 
 Yes, modems can reject common mode to some degree, but when that rejection isn't adequate for the situation,  a common mode rejector such as the RF3  improves it further, particularly when installed correctly.
The aim is improved S/(N+I) ratio, so improving performance may involve a bit of loss to give a nett improvement.  Anyone who is looking for a miraculous device with no snags will be disappointed ! 






 
Title: Re: SSFP Mk 3
Post by: les-70 on September 28, 2014, 09:33:44 AM

It needs figures from many caes !
 
 Yes, modems can reject common mode to some degree, but when that rejection isn't adequate for the situation,  a common mode rejector such as the RF3  improves it further, particularly when installed correctly.
The aim is improved S/(N+I) ratio, so improving performance may involve a bit of loss to give a nett improvement.  Anyone who is looking for a miraculous device with no snags will be disappointed ! 

  I did try to express the same cautions but thanks for repeating them as they are important. I fully agree on the many cases and I may change my tentative conclusions, for just my line, after a few days of testing.   I also would expect that on some lines an "RF3" type device may improve overall stability even if not the sync speed.

  My concern is that the general use of the Mark 2 and Mark 3 SSFP may be forcing everyone to have something that is detrimental to the performance of relatively good lines vdsl lines that use the D3 band.  Lines that don't use the D3 band would I suspect not notice much if any difference.

  After 15 hours the error rates witht the NTE-2005 are still lower than previously seen on my line with a 72Mb/s sync cap. 

Title: Re: SSFP Mk 3
Post by: JGO on September 28, 2014, 11:35:36 AM
If we had some figures on the RF3's  loss vs frequency that may answer your questions. Judging by photos there are several RF3 versions about too.

Remember xDSL uses an unlicensed radio receiver so there is no guarantee of zero interference and AIUI BT have no obligation to help.

BT's devices do help say 90% of cases of interference but compromise between performance and convenience so are not always optimum, (particularly when people install jammers  such as Plasma TVs', PLAs !! )  There is always a compromise in design; the RF3 could have a lower insertion loss, slightly benefiting maybe 1% of users,  at the expense of size and cost. 
Title: Re: SSFP Mk 3
Post by: boost on September 28, 2014, 11:46:46 AM
Thanks for sharing this les.

Some of the QLNs I see (ADSL2+) are a right state and if common mode interference isn't to blame, I guess there's an even bigger x talk issue going on than we realise!
Title: Re: SSFP Mk 3
Post by: burakkucat on September 28, 2014, 12:56:41 PM
To be utterly systematic about it, one would need to test:
in all the possible permutations.  ;)
Title: Re: SSFP Mk 3
Post by: les-70 on September 28, 2014, 04:11:46 PM
  I have all of those. I purchased with NTE-2005 and Mark3.  A Mark 1 came with an ebay HG612 and the Mark 2 with the FTTC install.

  Both the NTE-2005 and a Mark 1 were compared by me previously.  I think that for my line they are both "perfect" as far as they go. :--  The drop wires A and B go straight to RJ11 with no filtering.  I could not see any difference the between going through them and straight to the master socket and I also could not detect the addition of the house wiring or a ring and telephone call when either of these are used.

  The Mark 2 and 3 both have the extra toroid component that acts as an RF3 but giving relative to the RF3 relatively weak impact in the vdsl frequency bands. I would say they are RF3's designed to be acceptable on vdsl.   Whilst they may be acceptable it looks like the Mark 2 component took about 2-2.5 Mb/s off my attainable (~78Mb/s) due to attenuation in the higher frequencies mainly the D3 band.  BT may have recognized this and the Mark 3 gives a smaller reduction in attainable ( 1.0-1.5 Mb/s) on my line.  (see previous post for details and post http://forum.kitz.co.uk/index.php?topic=13420.msg259441#msg259441  to see by comparision how the RF3 itself hits a good vdsl line quite hard.)

 Please note that if your line is not using the higher frequency vdsl tones then I would expect that all the devices would test as near identical.  My line  had an atttainable of about 78Mb/s during my tests

I provisionally guess that my line does not need this extra common mode rejection and hence that I will be better off with without the toroid of the mark 2 and 3.   If my expectations work out I shall probably just do a little soldering and short out the toroid in the Mark 2.  I could equally use the NTE-2005 or Mark 1.   
Title: Re: SSFP Mk 3
Post by: burakkucat on September 28, 2014, 05:24:46 PM
Thank you for that explanation of your current observations and thoughts. In your situation I would be tempted just to use the Mk 1 SSFP, keeping the NTE-2005 in reserve and putting away the Mk 2 & Mk 3 in your grotto.

As I only have an ADSL2 service, the tones with frequencies much above 1 MHz are unusable. So your results are very valuable to know . . .  :)
Title: Re: SSFP Mk 3
Post by: les-70 on September 28, 2014, 06:22:09 PM
  Thanks for that b'cat.  Here is an aspect of the RF3's that I don't understand but does not seem good.  They seem to lift/create the QLN floor. I attach the Mark1 (now running) QLN which shows just a steady decline with increasing frequency.  Then the Mark 3 with its toroid RF3  and finally a real RF3 used between a Mark 2 and the modem.  i.e. a Mark 2 + RF3 although the RF3 will dominate.     They show that RF3 gives a raised floor at the higher frequencies, a weak effect with the Mark 3, but a strong impact with the RF3.

 Can anyone explain this? Whilst I have a very basic electronics understanding,  noise other than that of resistors is a bit beyond me and always looked a bit of a black art.

    Please ignore the variation in spikes between the plots.  The times on the plots are just the snapshot time and not the sync times to which the QLN refer.  Some look like evening but the RF3 is I am sure a daytime sync -it did not reduce my evening spikes.
Title: Re: SSFP Mk 3
Post by: JGO on September 29, 2014, 10:26:34 AM
There is an article on the web "The design of Ruthroff broadband voltage transformers - M Ehrenfried - G8JNJ"  which shows dips in the frequency response  due to differences in winding technique. (PDF doc 1.35Mb)    Something like this might explain the effects Les-70 is finding, since for the bandwidth ratio needed for VDSL, a Ruthroff technique seems essential. 

( for some reason the web address won't copy)
Title: Re: SSFP Mk 3
Post by: burakkucat on September 29, 2014, 04:35:48 PM
Putting that literal string ("The design of Ruthroff broadband voltage transformers - M Ehrenfried - G8JNJ") into Google brings up a list, with a link to the downloadable PDF document at the top.

If I have interpreted Google's output correctly, the URL is http://g8jnj.webs.com/Balun%20construction.pdf (Perhaps it is the space character between the words "Balun" and "construction" that causes a problem.)

It can be found on G8JNJ (http://g8jnj.webs.com/)'s web-page, as the first entry following the Baluns, Tuners & Matching heading. ("Problems with broadband transformers using Iron Powder Cores - why Ferrite cores give better results")

It can also be found here (http://www.indabook.org/preview/tiNTfHPXTOPB1isBhtQ4ERIme_6sdchUrJtyAMKjkHA,/The-design-of-Ruthroff-broadband-voltage-transformers.html?query=Design-Problems).

  :) 
Title: Re: SSFP Mk 3
Post by: JGO on September 29, 2014, 04:59:05 PM
Many thanks for the help B'cat.
 Yes that is the web page.  I just couldn't copy the address !!
Title: Re: SSFP Mk 3
Post by: burakkucat on September 29, 2014, 05:15:48 PM
Team-work prevails, once again!
Title: Re: SSFP Mk 3
Post by: les-70 on September 30, 2014, 07:32:45 PM
  I have now completed 3 days of testing the NTE-2005 or the Mark 1, which as noted above, are basically the same and seem to show the same results.

  The error rate has remained about 10% less with the fixed sync speed testing  :) .

 As implied above it seems that likely that many higher speed lines of ~60Mb/s and above may benefit from a 1-2Mb/s increase in sync if they change their Mark 2 and or 3 to the NTE-2005 or Mark 1.  If are they confident with a soldering iron they should get the same result by shorting out the common mode toroid on the Mark 2 or 3. In the event that the impact is adverse it would suggest that the line has common mode noise that needs rejecting
Title: Re: SSFP Mk 3
Post by: NewtronStar on September 30, 2014, 08:13:58 PM
Well les-70 have done most of the test's with RF3 in many location with and without the SSFP MK2 and found my line is better without any common mode toroid inplace, so I have replaced the BT80b RF3 with a standard BT80 and using the SSFP MK1.

All I can say is there great for adding a small amount of attenuation to your line and that's it, so my common mode testing has come to an end  :)
Title: Re: SSFP Mk 3
Post by: JGO on October 01, 2014, 07:02:43 PM
As I read your graphs, the Mk3 degrades S/N above about tone 4000 , roughly 17 MHz ? 

This is academic for anyone on any version of ADSL and many on VDSL too in the absence of interference.  With appreciable interference, the loss may be acceptable to give a nett gain on S/N+I on the lower tones.

It cannot be over stressed that NO filter is lossless; so don't jump up and down over a slight interference loss. I am in the situation that a 2 bit dip on tone 46 is due to the Droitwich transmitter. It can be removed with a RF3, but there is a slight nett loss.

  In basic English "You can't have jam on it !"

Les - We all owe you thanks for finding the limitations of the RF3 type devices.

BUT, and I think you agree with me, it should not put off anyone on lower BW VDSL or any ADSL from using a potentially useful device.
It just isn't a magic cure all !!!   

     
Title: Re: SSFP Mk 3
Post by: boost on October 01, 2014, 07:30:20 PM
I only load 6 bits on tone 46 too... this mk3 plate is akin to an RF3, yes?
Title: Re: SSFP Mk 3
Post by: JGO on October 01, 2014, 08:09:40 PM
I only load 6 bits on tone 46 too... this mk3 plate is akin to an RF3, yes?

It contains a similar device yes. 

Two possibilities for you, - pickup on unprotected cable between faceplate and modem,
or/and pickup on the modem's powerline.
Title: Re: SSFP Mk 3
Post by: les-70 on October 01, 2014, 08:13:57 PM
I said before
  Please note that if your line is not using the higher frequency vdsl tones then I would expect that all the devices (SSFP's) would test as near identical.   
and
   In the event that the impact is adverse it would suggest that the line has common mode noise that needs rejecting

  Whilst I am getting a small positive impact from removing the common mode choke. I tried not to be prescriptive re other lines. The loss with Mark 2/3 is quite small and at the highest VDSL frequencies.  It is a matter of fact that you can't insert a common mode choke without some loss.  My impression is that a bifilar common mode choke could have reduced the loss and if BT wish to impose the common mode choke as default rather than as an option it is pity they did not use one.

   To Boost.  Others are more expert but I suspect the RF3 should be much better at common mode rejection in the ADSL tones than the Mark 2/3 common mode choke.  The Mark 2/3 choke is seeking to have limited attention of the high vdsl frequencies which will work against is being so effective at ADSL frequencies. 

 
Title: Re: SSFP Mk 3
Post by: boost on October 01, 2014, 08:43:56 PM
Thanks.

Time to throw 3 quid into the cloud and then slap one of these (http://www.run-it-direct.co.uk/BT80BRF3.html) just before the modem!
Title: Re: SSFP Mk 3
Post by: burakkucat on October 01, 2014, 09:06:55 PM
Time to throw 3 quid into the cloud and then slap one of these (http://www.run-it-direct.co.uk/BT80BRF3.html) just before the modem!

Perhaps do as N*Star did and customise an RJ11 - RJ11 lead so that the BT80B-RF3 is as close to the modem as possible?  :-\
Title: Re: SSFP Mk 3
Post by: boost on October 01, 2014, 10:35:11 PM
I'll try :)
Title: Re: SSFP Mk 3
Post by: loonylion on October 04, 2014, 02:16:50 PM
So if I'm reading this right, I should have no insertion loss from fitting one of these because the loss is all in the tone bands I already can't use? (using U0, U1, D1, D2)
Title: Re: SSFP Mk 3
Post by: burakkucat on October 04, 2014, 02:29:44 PM
Er, not quite.  :-\

Insertion loss will be present across the entire spectrum but the devices have been designed such that in an average, typical case the benefit obtained by fitting such a device (by reducing the effect of RF ingress to the circuit) should outweigh the attenuation of the wanted signal.

Hopefully I have made sense . . . If not, I'm sure others (such as JGO) will assist.  ;)
Title: Re: SSFP Mk 3
Post by: JGO on October 04, 2014, 03:04:25 PM
Er, not quite.  :-\

Insertion loss will be present across the entire spectrum but the devices have been designed such that in an average, typical case the benefit obtained by fitting such a device (by reducing the effect of RF ingress to the circuit) should outweigh the attenuation of the wanted signal.

Hopefully I have made sense . . . If not, I'm sure others (such as JGO) will assist.  ;)



Yes agree 100%  B'kat
The point is that the device has a limited bandwidth in Hz in which the loss is acceptable.  It is perfectly good for say ADSL suffering from moderate interference, but with Les-70's fast VDSL it has an adverse effect, unless there is a lot of interference. You have to weigh the loss of interference against loss of signal.

It will be pretty useless on the (lab tested only)  super VDSL !!!
 
Title: Re: SSFP Mk 3
Post by: atkinsong on October 05, 2014, 01:09:10 PM
I wonder if BlackSheep could update us on whether the Mk3 has officially appeared within OR yet?

If so I would be interested to find out what the official line is.
Title: Re: SSFP Mk 3
Post by: Black Sheep on October 05, 2014, 08:55:54 PM
Yes, it is now a stores item .......... however, we don't get the technical data afforded to the latest release !! Yes, it's a bl00dy joke that we don't, but it is what it is.  :)
Title: Re: SSFP Mk 3
Post by: Alex Atkin UK on October 05, 2014, 11:31:05 PM
Kelly Communications fitted my brand new fibre install with a MK3 on 17th September, so they are definitely in circulation.

The engineer actually made a bit of a song and dance about it saying they were being told NOT to fit them but he personally always does because they are better.

Obviously what we have found here that its not exactly true, especially as I have a short line with an attainable rate of 95350, well above BTs profile cap.

Interestingly, my main line when on Digital Region (currently unused due to problems migrating back to BT) used to get an attainable rate of 108636.  I assumed that the lower rate I get now was down to being a physically different line perhaps combined with BT using different band plans.  However, it sounds like the MK3 may also be a factor and I'm really curious now to find out.

Unfortunately the NTE-2005 is busy connecting the extension on my main line so I would have to pick a time when I am unlikely to get any phone calls to test it.
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 06, 2014, 08:20:19 AM
on my line the MK2 reduced attainable by about 0.6mbit and increased D1 attenuation by about 1.5db, no affect on D2 and D3 attenuation.

Initial impressions are it was helping on CRC, when I had the MK2 in most errored seconds were 1-2 CRC, without it they higher.

I still have yet to try the MK3.  I currently have the MK1 back in.
Title: Re: SSFP Mk 3
Post by: les-70 on October 06, 2014, 09:46:49 AM
  Testing the error rate is a hard thing to do.  I had lower errors with the NTE-2005 and HG612 in a test over 3 days. However if i look back at my stats over a long period that is not really a reliable test on my line. It definitely means the error rate over the 3 days was not significantly different from the usual 3 days and was "possibly" lower.  I was currently doing a longer test but it needs weather with no nearby thunderstorms and the weather forecast week this does not look good for such testing. 

  @Chrysalis  Are you using the XyXel ... for your tests?  I noticed that the Billion 8800NL did not get so much of a gain from removing the Mark 2 as the HG612.  The 8800NL like the ZyXel makes a bit more use of the higher tones that the Mark2 attenuates so I had wondered if it do even better, but no, it was the HG612 that seemed to benefit most. Maybe the  Billion and ZyXel are able, in part, to see signal though the some of the Mark 2 attenuation and thus don't benefit so much ??  hard to say.
Title: Re: SSFP Mk 3
Post by: Alex Atkin UK on October 06, 2014, 10:39:56 AM
Haven't been able to try with the NTE-2005 but I just tried with an old ADSL filter into the test socket and my attainable was worse than the MK3.

I was surprised it made such a difference, even if the ADSL filter does have an inch of flat cable. (I bet its not twisted pair)

Code: [Select]
Generic ADSL Filter: 94816 down 31959 up
Openreach MK3:       95290 down 32318 up

Granted my drop wipe is blowing around like a chinese lantern right now. ;)  But the MK3 attainable was around the same before and after the swap.  I had expected if anything for the generic filter to be higher as its unlikely it has anything filtering the DSL side.

I was hoping to use the adapter from the Dreamcast that converts RJ11 directly to BT plug, thus not having any filter at all.  Alas, I can't find the darn thing.
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 06, 2014, 12:43:53 PM
no I didnt use a device designed for adsl :p

I am using the MK1 now.
Title: Re: SSFP Mk 3
Post by: Alex Atkin UK on October 06, 2014, 02:04:51 PM
Its worth noting, I do not use the phone side of this line as this is a second line just for broadband as the intention was to have dual-fibre connections and load balance them.  However a tag problem has prevented me getting fibre on my primary line.
Title: Re: SSFP Mk 3
Post by: burakkucat on October 06, 2014, 04:19:28 PM
Just to clarify --

A generic (ADSL) microfilter only contains a low-pass filter which is in the circuit between the 431A (BT) plug and the corresponding (BT) socket. The RJ11 socket is directly connected to the 431A plug.

So Alex's test is valid for the case where the circuit is not used for telephony purposes.

I have a couple of leads with a (BT) 431A plug at one end and an RJ11 plug at the other end. Usage of one of those leads "does away" with the need to use any form of adaptor.  :)
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 06, 2014, 05:17:39 PM
where do you get those leads from?

when I once used a nte-2005 on my adsl it lost about a mbit of sync, also on vdsl I tried it last year sometime and lost about 20mbit of sync speed.

needless to say its now in the bin :)
Title: Re: SSFP Mk 3
Post by: les-70 on October 06, 2014, 05:47:29 PM
  An NTE-2005 should never cause such speed losses unless it was severely faulty.  The BT line goes straight through it with no more attenuation than that caused by the extra socket contacts.  The telephone side is filtered off and that would be the part that have to fail to give an adverse impact.
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 06, 2014, 06:31:44 PM
back to mk1, vs mk2/3

today the combo of zyxel+mk1 has had the most errors I seen for while and I think ES count is up also.  My modem even resynced earlier I assume due to errors it couldnt handle.  Even capped to 72mbit the error rate is not good compared to before, tomorrow I will restore the MK2 or put the MK3 in.
Title: Re: SSFP Mk 3
Post by: les-70 on October 06, 2014, 06:44:28 PM
  There is some lightning in the west of Wales this evening and it is moving east, so conditions at the moment are not good for judging things.
Title: Re: SSFP Mk 3
Post by: burakkucat on October 06, 2014, 07:39:47 PM
where do you get those leads from?

Any on-line retailer. I either used eBay's market place or Amazon . . .  :)

Here is a link (http://www.ebay.co.uk/itm/1M-BT-PLUG-TO-RJ11-CABLE-TELEPHONE-LINE-CORD-6P4C-BROADBAND-MODEM-ROUTER-LEAD-/360675147533) to an example.
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 06, 2014, 08:40:28 PM
ok thanks
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 06, 2014, 09:43:13 PM
back to mk1, vs mk2/3

today the combo of zyxel+mk1 has had the most errors I seen for while and I think ES count is up also.  My modem even resynced earlier I assume due to errors it couldnt handle.  Even capped to 72mbit the error rate is not good compared to before, tomorrow I will restore the MK2 or put the MK3 in.

Yes you had 80 errored seconds at 15:00 and the errors fall down to 4 at 20:00 is this down to MK1 ? no two lines are the same even with the same attenuation but looking at your before and after your CRC's and ES's looked better with the MK2
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 07, 2014, 12:30:09 AM
confirmed les-70 having a T/Storm at 00:29 lot's of Cloud to ground strikes it's amazing
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 07, 2014, 08:36:18 AM
putting back in today newtron, the errors improvement maybe down to me capping the sync to 72.

it is possible the higher errors yesterday are due to the rain, and its raining again today so will see.
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 07, 2014, 11:32:52 AM
ok mk3 is back in here is data for almost hour, crc and ES close to each other again.
unlike the mk2 I havent loss sync speed and also had no/little effect on attenuation.

Title: Re: SSFP Mk 3
Post by: NewtronStar on October 08, 2014, 07:16:38 PM
ok mk3 is back in here is data for almost hour, crc and ES close to each other again.
unlike the mk2 I havent loss sync speed and also had no/little effect on attenuation.

Just had a look at MWS your crc's and es's seem to have got worse in the last 24 hours.
Title: Re: SSFP Mk 3
Post by: Chrysalis on October 08, 2014, 07:18:44 PM
they were good at first

but its been a lot of rain and I think is killing the line.

I went upstairs and looked at junction box and is filled with water, no lid on it.

The same junction box that has never been checked since years ago.
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 08, 2014, 08:05:37 PM
I went upstairs and looked at junction box and is filled with water, no lid on it.

Thats mad Chry, I know it's the OpenReach side of things but if was me I would be up the ladder and do DIY job on it  :-X
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 11, 2014, 08:06:41 PM
This I can't get my head around with the SSFP MK2 inplace the US errored seconds becomes more noticeable with a loss of US attainable in the stats during the day time and with the SSFP MK1 inplace there is less US errored seconds and more US attainable 24/7
Title: Re: SSFP Mk 3
Post by: burakkucat on October 11, 2014, 08:47:51 PM
Beginning at 0 Hz and moving upwards to higher frequencies, first we see the (audio) frequency band of the telephone service then next comes the xDSL US frequency band.

If the low-pass filter of the Mk 2 is "less precise" then the low-pass filter of the Mk 1 then perhaps the upper reaches of the telephony band manage to "escape" into the "bottom" end of the xDSL US band?  :-\  Or perhaps not . . .
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 11, 2014, 09:40:36 PM
Beginning at 0 Hz and moving upwards to higher frequencies, first we see the (audio) frequency band of the telephone service then next comes the xDSL US frequency band.

If the low-pass filter of the Mk 2 is "less precise" then the low-pass filter of the Mk 1 then perhaps the upper reaches of the telephony band manage to "escape" into the "bottom" end of the xDSL US band?  :-\  Or perhaps not . . .

So this is normal then ?
Title: Re: SSFP Mk 3
Post by: burakkucat on October 11, 2014, 09:55:46 PM
No. I wouldn't think so.

What you really need is the loan of a spectrum analyser so that you could compare the behaviour of each SSFP.
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 11, 2014, 10:57:42 PM
No. I wouldn't think so.

What you really need is the loan of a spectrum analyser so that you could compare the behaviour of each SSFP.

Please no more tech equipment i'll have my hands full next week when the RPi arrives it's got a 8GB Noobs card, the last time I saw that word was when running World of Warplanes and the other team called us Noobs  :D
Title: Re: SSFP Mk 3
Post by: sheddyian on October 12, 2014, 12:43:38 AM

Please no more tech equipment i'll have my hands full next week when the RPi arrives it's got a 8GB Noobs card, the last time I saw that word was when running World of Warplanes and the other team called us Noobs  :D

Be careful - Raspberry Pis are like cats.  I got one in 2012, and now I have 4, thinking of getting a fifth.  They multiply!

Ian
Title: Re: SSFP Mk 3
Post by: loonylion on October 12, 2014, 01:10:59 AM

Please no more tech equipment i'll have my hands full next week when the RPi arrives it's got a 8GB Noobs card, the last time I saw that word was when running World of Warplanes and the other team called us Noobs  :D

Be careful - Raspberry Pis are like cats.  I got one in 2012, and now I have 4, thinking of getting a fifth.  They multiply!

Ian

I have 3 lol, 2 model Bs and a B+
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 12, 2014, 05:27:40 PM
Be careful - Raspberry Pis are like cats.  I got one in 2012, and now I have 4, thinking of getting a fifth.  They multiply!

Ian

Yes cat's are loveable pets until they don't come back for whatever reason lost 2 cats in the space of 8 weeks it breaks your heart.

Think I'll stick with just the one RPi and our last cat my avatar Ceaser he's more like dog than a cat always beside me.

Title: Re: SSFP Mk 3
Post by: Black Sheep on October 13, 2014, 09:59:46 AM
they were good at first

but its been a lot of rain and I think is killing the line.

I went upstairs and looked at junction box and is filled with water, no lid on it.

The same junction box that has never been checked since years ago.

Could you take a picture and show us this junction box please ?? I've never known overhead JB's fill with water.

For info ….. we don't go round randomly checking DP's/JB's …… that would be madness. We are tasked with resolving the issue, only if we are working actually on the plant itself. If we aren't working on the plant, but espy defective issues whilst passing, we can input an A1024 for remedial work to be carried out.
Or ….. as someone who monitors there broadband line every day, you yourself could ring Openreach and raise an issue ??. This will see any defect get resolved a lot quicker. 

Title: Re: SSFP Mk 3
Post by: Chrysalis on October 13, 2014, 01:48:40 PM
Well i had to go in my neighbour's flat, I dont have free access. I was in there doing something for her, and had a look then.

But will try to take a pic.  It is possible I guess there is a lid thats below the edges of the box and the water was on top of that.
Title: Re: SSFP Mk 3
Post by: Black Sheep on October 13, 2014, 05:04:52 PM
If you (as a friend and neighbour) don't have "Free access", then the chances of us checking is going to be limited to say the least ??

"It is possible I guess there is a lid that's below the edges of the box and the water was on top of that".

Anybody that owns a premises, let alone a million-plus jointing points, will appreciate that halting the ingress of water is nigh-on impossible, especially in underground enclosures. If it's above ground, then none of the closures are waterproof, as the water will drain by the laws of gravity, for that reason there is no "Edge of boxes".
They do have a certain level of 'splash' protection afforded to them (Equivalent, I would imagine, to the electrical regs IP index), but nothing else is required due to the afore-mentioned laws of gravity.

Title: Re: SSFP Mk 3
Post by: les-70 on October 23, 2014, 07:20:26 PM
  I decided to have go at doing a better job of adding a common mode choke to the Mark 1 perhaps to make a Mark 4  :).  From reading references earlier in this thread it is disappointing that the Mark 3 choke is not bifilar as a bifilar choke should be able to do a much better job on the common mode with much less differential mode impact.

   I have taken a ferrite toroid with Al value 12 micro Henry and wound my adsl lead round it.  I have tried 10 turns, 7 turms and 5 turns and settled on 5 turns for a ~70Mb/s connection.  For a  lower sync speed more turns should be better.  5 turns gives me a sync speed loss of about 1Mb/s (similar to a Mark 2) more turns give a bigger reduction.   I attach Hlog with and without the toroid and a phote of the toroid itself.  In Hlog you can see the differential mode attenuation starting to bite.  That should have the effect of stopping any higher frequencies saturating the modem input stage.   The common mode attenuation can be calculated from the Al value and number of turns and should be enough to give good common mode rejection over the vdsl band.

 Unlike the Mark2 and mark 3 this arrangement does have a helpful impact on my errors.   :)  I have been using it for 3 days and the whilst the ES are down a bit the CRC and SES are down much more.   I will need a week more to give a confident outcome but I like being able to control the filter with the number of turns
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 23, 2014, 07:54:13 PM
I replaced my old worn bathroom pull switch guess what no more crc's or errored seconds when someone pulls that cord, tbh have given up all hope on MK's it much easyier to find the cause in the household and fix it than getting an MK Device that supposedly subdues the effects of rein.
Title: Re: SSFP Mk 3
Post by: burakkucat on October 23, 2014, 09:08:20 PM
phote of the toroid itself.

Looking at the picture, I make that six turns of the cable on the toroid.  :-\
Title: Re: SSFP Mk 3
Post by: burakkucat on October 23, 2014, 09:09:31 PM
I replaced my old worn bathroom pull switch guess what no more crc's or errored seconds when someone pulls that cord,

A definite result! :clap2:
Title: Re: SSFP Mk 3
Post by: les-70 on October 23, 2014, 09:32:26 PM
  It is indeed 6, I clearly can't count!  :(  If you believe Wikipedia that makes the individual inductance's  in extra of the cables of the pair as 12*36 =432 micro H. with an impedance of 2.714 Kohms at 1Mhz and more than enough to kill any common mode.  I wonder how much of any benefit comes from the common mode rejection vs. just attenuating the higher than vdsl frequencies that might saturate an input stage.
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 23, 2014, 09:33:41 PM

A definite result! :clap2:

It is and the kitchen also has a pull switch which shows up as crc's and errored seconds when pulled so that's another 45 min replacement job, if it was not for Dslstats or HG612_Modem_stats I would never have been able to see the correlation how a switch can effect the modem  :)
Title: Re: SSFP Mk 3
Post by: boost on October 23, 2014, 09:43:49 PM
wp les!
Could I try this for good ole ADSL1? 702 turns maybe? :D
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 24, 2014, 12:21:30 AM
You can make your own mind up as I have removed the MK2 tonight it's been inplace for over two weeks and replaced it with the standard SSFP, to me the SSFP MK1 is less sensitive to LCD and LED monitors.

when the MK2 was inplace it impacted my SNRM big time when LCD and LED TV's & Monitors were on can't figure that out.

With the standard SSFP inplace there is less US CRC & Errored seconds when the phone rings again can't figure that out, now I haven't tried out the MK3 because I hate wasting money  ;)
Title: Re: SSFP Mk 3
Post by: les-70 on October 24, 2014, 07:45:33 AM
wp les!
Could I try this for good ole ADSL1? 702 turns maybe? :D

  The point is that with bifilar winding the common mode rejection is much much greater relative to the mostly unwanted differential mode attenuation and even with 6 turns that toroid may/probably outperform an RF3 in common mode rejection.  Even if you wanted to optimize the differential mode attenuation for adsl, it is not quite that many turns!  Inductance is proportional to turns squared.  Ideally you might need about 24 turns but as many as you could fit on that toroid, about 11 with the lead shown, should very greatly outperform an RF3.  Unless it is needed it still won't make any difference to the connection though!! (Most of the rubbish we would all like to reject is differenial mode at the actually signal frequency and that can't be just filtered out.) Those extra turns are not needed to reject any common mode but just to attenuate differential mode at higher than adsl2 frequencies, the result would be a vdsl killer. See pages 7 and 8 in link.

  http://www.we-online.com/web/fr/index.php/show/media/07_electronic_components/toolbox_1/product_training/Product_Training_CMC_100728.pdf
Title: Re: SSFP Mk 3
Post by: boost on October 25, 2014, 02:10:48 PM
Cheers, I will have a squint :)
Title: Re: SSFP Mk 3
Post by: Ixel on October 26, 2014, 10:29:38 AM
I have taken a ferrite toroid with Al value 12 micro Henry

Is it possible to buy one of these (most probably a pack) online? I'm not an electronics expert so no clue what I'm looking for other than a ferrite toroid which has a diameter large enough for the RJ11 plug to fit through so I can wind it round the ferrite toroid. I presume ferrite toroids have varying thicknesses and dimensions, and 'Al value 12 micro Henry?'. I'm interested in trying this, I've been trying various methods to eliminate/minimise CRC errors on my downstream but nothing as customised as this. Any help is appreciated. Thanks.
Title: Re: SSFP Mk 3
Post by: les-70 on October 26, 2014, 11:02:01 AM
   Having had a longer test run,  an error reduction has remained but only about 20-30%.  I have now gone back to 11 turns to see if that does any better (which is most I can manage with my twisted pair cable).  The extra loss in sync with 11 turns is much less that I would have expected, I guess the  capacitive coupling part these devices is very hard for any non expert such as me to judge.   13 or 14 turns are possible with the usual modem supplied RJ11 leads.  The worst issue with all filters is that you just can't eliminate any unwanted differential signal in the adsl or vdsl tone band without taking the needed signal away at the same time. 

   It is also worth noting that I have a noisy line and probably more to try to get rid of.

  I would not expect too much.  The one I have is from

 http://www.ebay.co.uk/itm/290913639269?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

  It came in about a week.

Title: Re: SSFP Mk 3
Post by: Ixel on October 26, 2014, 11:21:43 AM
Thanks. I've now ordered one and a MK3 SSFP. I'll post a conclusion when I've tested for a bit.
Title: Re: SSFP Mk 3
Post by: JGO on October 26, 2014, 12:34:00 PM
In my case I suspect that many CRCs are due to nearby thunderstorms. In that case there is so much interference power there that NO practicable filter could reduce it below the systems's acceptable noise, even if the filter does an adequate job on say, street lights.
Title: Re: SSFP Mk 3
Post by: burakkucat on October 26, 2014, 03:07:08 PM
. . . (which is most I can manage with my twisted pair cable).

I'm unsure Les but when using an UTP cable can it then actually be regarded as a bifilar winding? The tingle I currently feel in my whiskers seems to be hinting at "No".  :-\
Title: Re: SSFP Mk 3
Post by: les-70 on October 26, 2014, 03:53:04 PM
  Good question - I don't think it matters ?   Before starting I had a look at the Wurth web site for into.  They say bifilar chokes can be wound as parallel pairs or twisted pairs and sell both but I could not spot anything about the difference.  My limited sense of electro magnetics is that it should not make any difference provided the two wires are wound close together in the same sense. 
Title: Re: SSFP Mk 3
Post by: burakkucat on October 26, 2014, 05:08:17 PM
Thank you for sharing that information. Perhaps I haven't given it sufficient thought.  :)
Title: Re: SSFP Mk 3
Post by: Dwight on October 26, 2014, 10:37:42 PM
Hi Guys,
Quick question on the MK3 does it need the IP plate as well? As my cable length doesn't allow for both.
Cheers
Title: Re: SSFP Mk 3
Post by: burakkucat on October 26, 2014, 11:24:22 PM
Quick question on the MK3 does it need the IP plate as well? As my cable length doesn't allow for both.

The SSFP is fitted to the front of the NTE5A, once the lower front pace-plate has been removed. Then the lower front face-plate is attached to the front of the SSFP.

If the above does not make sense in relation to what you currently have fitted, then it might be best for you to take a picture and share it so that we can see exactly what is what.
Title: Re: SSFP Mk 3
Post by: Dwight on October 28, 2014, 06:05:02 PM
Hi BC,
Yep, know that the all plug together, I just need to know if I need them all!
Wall plate, IP plate, MK3 with ADSL socket, and then Phone plate. So do I need the bit in red?
Cheers
Dwight
Title: Re: SSFP Mk 3
Post by: Black Sheep on October 28, 2014, 06:06:47 PM
No, leave the IP Plate out.  :)
Title: Re: SSFP Mk 3
Post by: burakkucat on October 28, 2014, 08:14:23 PM
You most definitely do not need one of the original iPlates fitted to the NTE5/A.  :no:

Not required --
Title: Re: SSFP Mk 3
Post by: Dwight on October 31, 2014, 07:52:47 PM
Thanks I will send to the recyclers!  :)
Title: Re: SSFP Mk 3
Post by: NewtronStar on October 31, 2014, 09:47:46 PM
I think the iplate uses the same toroid as the BT80 RF3 if I'm correct the iplate was supposed to be a booster for ADSL :D
Title: Re: SSFP Mk 3
Post by: Black Sheep on November 01, 2014, 08:55:26 AM
It provided a similar function to physically removing the 'Bell-wire' from terminal 3. Re-balancing the circuit this way, actually provided massive gains in some dwellings.
Title: Re: SSFP Mk 3
Post by: Bigmac77 on November 03, 2014, 12:30:39 PM
I have just replaced a BT ADSL V1.0 with a Mk3 and it has added 150 Kbps to my sync rate. Not much but I have a 54dB attenuation so every little helps. Just hope the line holds at this higher rate.
Title: Re: SSFP Mk 3
Post by: VDSL2User on November 03, 2014, 03:07:15 PM
Well inspired by les-70 and his 6 turn Toroid I wondered if it may assist my error rates.
I am using a MK3 faceplate, HG612 and Asus RT-N66U
The core arrived today and I have used 7.5 turns on it.
It is much to earlier to get real information BUT I was running since last night at 20-40 ES per hour
right up until I switched off for 30 minutes around 11am today.
Since restarting with the Toroid in place I have had 2hr and 10 mins with only 18 ES in total !
Fingers crossed this continues and I have been able to reduce the ES rate by a significant factor.
My stats can be found at MyDSLWebStats under the user VDSL-User if anyone wants to check or follow progress.
Title: Re: SSFP Mk 3
Post by: Dray on November 03, 2014, 03:18:56 PM
Is the modem cable UTP already?
Title: Re: SSFP Mk 3
Post by: VDSL2User on November 03, 2014, 03:38:39 PM
My modem cable is a (cheap) simple flat 1.5m 2 core (none twisted pair) with RJ11 both ends.
Title: Re: SSFP Mk 3
Post by: Dray on November 03, 2014, 03:57:27 PM
I think a CAT5 cable using 1 pair may work as well as a ferrite ring
Title: Re: SSFP Mk 3
Post by: VDSL2User on November 03, 2014, 04:21:04 PM
Not for my line it would appear, was previously using a 1m CAT6e cable with RJ45 to RJ11
The current setup is starting to see more ES but is still lower than I have been seeing, only
a longer run of a few days will tell if there is a real improvement.
Title: Re: SSFP Mk 3
Post by: Ixel on November 03, 2014, 04:45:23 PM
Have got the ferrite toroid this morning. So far it seems as if I'm getting more ES than when I didn't have it. I've got the standard RJ11 flat cable running through it on 5 turns. My statistics are on MyDSLWebStats for anyone curious.

http://82.68.184.44/dslstats/2014-11-03/Bitswap-2014-11-03-16.46.00.png (http://82.68.184.44/dslstats/2014-11-03/Bitswap-2014-11-03-16.46.00.png)

A lot of bitswapping going on around tones 3100 to 3400 or so. Could that perhaps be where the CRC blips are coming from?
Title: Re: SSFP Mk 3
Post by: Dray on November 03, 2014, 04:53:58 PM
Sorry, I don't know what CAT6e cable is. Is it shielded CAT6 ?
Title: Re: SSFP Mk 3
Post by: VDSL2User on November 03, 2014, 05:26:16 PM
Yes CAT6e is the shielded version of CAT6 and currently the best version available for high speed.
Title: Re: SSFP Mk 3
Post by: Dray on November 03, 2014, 05:50:51 PM
Was the shield grounded?
Title: Re: SSFP Mk 3
Post by: VDSL2User on November 03, 2014, 06:13:36 PM
I don't know how anyone would ground the wrapped shielding on a wall to modem cable,
where would you ground it to ? and might this not create a voltage potential across the incoming
BT line ?
The cable that was in use was this one http://www.ebay.co.uk/itm/DSL-LEAD-CABLE-for-BT-INFINITY-FTTC-VDSL-Choose-CAT5E-CAT6-and-LENGTH-needed-/350682964560?pt=LH_DefaultDomain_3&var=&hash=item51a6556250 (http://www.ebay.co.uk/itm/DSL-LEAD-CABLE-for-BT-INFINITY-FTTC-VDSL-Choose-CAT5E-CAT6-and-LENGTH-needed-/350682964560?pt=LH_DefaultDomain_3&var=&hash=item51a6556250)
MY ES rate has increased again now, however it is always very bad from 5pm to 10pm so it will be interesting to
see how bad it gets and how well it does overnight.
I guess my line is just subject to a lot of external interference which is most noticeable in the early evenings.
It will only stay on fast path if speed limited to the speed normally obtained in interleave mode.
Title: Re: SSFP Mk 3
Post by: Dray on November 03, 2014, 06:51:58 PM
From looking on Google as I've not heard of CAT6e, I thought the only difference was a grounded shield. But from the link you provided it doesn't say CAT6e anyway so I remain confused. To me, the important attributes are pure copper 0.5mm thick, twisted pair. Although one supplier I bought from supplied me with copper coated aluminium or aluminium magnesium copper alloy wires and when I complained, pointed out it wouldn't make a noticeable difference over 50cm anyway.
Title: Re: SSFP Mk 3
Post by: les-70 on November 03, 2014, 07:12:27 PM
  The vdsl signal gets all the way from the cabinet on CW1308 (CAT4) so the last metre does not make much difference and, whilst a twisted pair of the same CW1308 spec is ideal for the dsl lead, the last metre has little impact.
Title: Re: SSFP Mk 3
Post by: pooclah on November 07, 2014, 04:44:49 PM
I swapped my MK3 back to the MK1 this morning, not much difference in the stats at the moment but I will keep an eye on it.  There was a bit of strangeness with the upstream SNRM immediately after the resynch (pic below)  but it seems to have settled now so probably something else disturbing the line.
Title: Re: SSFP Mk 3
Post by: loonylion on November 08, 2014, 03:48:27 PM
Well I decided to get a 12 microhenry toroid to try it out, but before I got the chance to try it, my dad appropriated it for my sister's TV. 2 turns of the aerial cable around the toroid and 0% signal quality at 66% strength became 100% quality at 66% strength. Quite an impressive result for that particular application.
Title: Re: SSFP Mk 3
Post by: NewtronStar on November 08, 2014, 08:25:16 PM
Well I decided to get a 12 microhenry toroid to try it out, but before I got the chance to try it, my dad appropriated it for my sister's TV. 2 turns of the aerial cable around the toroid and 0% signal quality at 66% strength became 100% quality at 66% strength. Quite an impressive result for that particular application.

Loonylion there is more to than winding the cable around a ferrite core so have injected a link into my post  http://www.wirelesswaffle.com/index.php?entry=entry120211-055210 (http://www.wirelesswaffle.com/index.php?entry=entry120211-055210)
for the DIYers to look at.
Title: Re: SSFP Mk 3
Post by: loonylion on November 08, 2014, 09:30:53 PM
I'm using vdsl and trying to reduce my error rates a bit, line is perfectly stable. Les-70 got interesting results wrapping the modem cable around a toroid so that's what I'm trying to replicate.
Title: Re: SSFP Mk 3
Post by: NewtronStar on November 09, 2014, 12:19:48 AM
I'm using vdsl and trying to reduce my error rates a bit, line is perfectly stable. Les-70 got interesting results wrapping the modem cable around a toroid so that's what I'm trying to replicate.

No worrys give it a go  :) my link was to show the circuitry and componets needed to make a DIY RF3 unit. 
Title: Re: SSFP Mk 3
Post by: les-70 on November 09, 2014, 10:59:14 AM
  First let me warn that the 12microH Al toroid that I used is of an unspecified ferrite material that may or may not be ideal.  Given the high value of Al for the size it may be a lower frequency material that will be OK with lowish numbers of turns but may not be so effective with a high number of turns.
The working frequency drops with the number of turns.

 N*'s article is good in also having a bifilar choke but whilst the type of magnetic material is usefully noted the actual size and number of turns seem equally pot luck.   The low pass filter in the article should mention the need to check the operating frequency of the chokes is OK and all the filters noted would almost totally remove vdsl signals leaving just the adsl2 frequencies.  A vdsl version could be made with different value components.

The RF3 is just a common mode choke with no explicit low pass filter but the inevitable capacitances in any choke do give some differential mode low pass filtering and the RF3 takes about 10Mb/s off a vdsl line with an attainable of about 70-80.  The Mark2 and Mark3 SSFP's both include a common choke already and the ones used are intended for vdsl and only take about 0.5 to 1 Mb/s sync of a 70-80 vdsl line.  The extent of common mode removal would be expected to be better had the SSFP's used a bifilar choke. 

 My aim was just to do that bit better with a bifilar choke. On my line it gives reduction in the ES rate of 10-20% -- so little as to take days to be sure of it.  It does however at least halve the number of CRC and SES that I get. 

  Finally the input stage of the modem will to some extent do all these filtering operations.  I would guess most lines would not get a noticeable benefit unless the there really is a large common mode RFI/REIN  issue on the line.   If you are picking up differential mode interference no RF3 type of device will be of much help..