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[hyeung]

Is it because my router type is not fully compatible?
Its a DG834PN....so is not the exact model its was meant for?

Also notice that the Summary tab does not show all the information as one expects.
I can only see the noise margin figure in the downstream....everything else appears to be blank?

Downstream (RX)
Connection Rate:   Kbps
Line Attenuation:  dB
Noise Margin:     12 dB

Interleave CRC:   0
Interleave FEC:   0
Interleave HEC:   0

Fast path CRC:    0
Fast path FEC:    0
Fast path HEC:    0
Upstream (TX)
Connection Rate:   Kbps
Line Attenuation:  dB
Noise Margin:      dB

Interleave CRC:   
Interleave FEC:   
Interleave HEC:   

Fast path CRC:   
Fast path FEC:   
Fast path HEC:   

Also, whats the difference between the Noise Margin and the Rx Noise tabs (see attachments)?

Any ideas on the bits/tone....is it the router?
The only other router i have is a billion 7402NX....but i don't think its supported in routerstats.
What do u reckon now?

[attachment deleted by admin]

[Ezzer]

This sounds like REIN and possibly a case where a 444b tester would be of more help than a radio. Unfortunately this means a REIN engineer turning up at the time the problem occurs with the 444.

The siting of the cabinet shouldn;t be any more significant than any other joint along the line in picking up any REIN being transmitted back down the phone line. Although it makes it handy for a REIN guy as a place to check if it is something feeding back down the phone lines.

The hawk can do a whole range of tests. good to hear you've had a balance check as this indicates a thorough check for any conditions on the line. but a hawk dos'nt measure snr. only via a dsl connection can this be realisticly measured. All the hawk tests would be making sure you line is as invenerable to any such affects as possible.

The only other thing is listen to the noise off your dsl cable to the router when it's in sync. When you loose sync, disconnect this lead from the router so you dodn;t hear your dsl signal or the router trying to train for a signal. then listen to any noise from the dsl cable whilst it's still plugged into the phone socket. should be quiet with no distinct sounds from thr radio. Also try the radio at other harmonics. that is double, treble the frequency or at the points in between. (the only problem with this is your getting further away from the key frequency around 300khz, the 612khz being the next major harmonic up, this is used because a typical radio dosn't have a range much below 570khz. the 444b can listen to 0 to 1mhz through out the range which can be both a boon and a drawbackover using a radio)

[roseway]

Concerning Routerstats:

The two graphs should show substantially the same information - they both actually refer to noise margin. The DG834PN is fully compatible with Routerstats; it uses the same Broadcom chipset as the DG834GT.

I really don't understand why the two graphs are so different, or why other data isn't displayed correctly. It might be worth joining the Routerstats forum and asking there.

[waltergmw]

Hi Hyeung,

Although all the pictures are different they are showing similar sets of data. What you are mainly looking for are those tones which are carrying zero or only a couple of bits.

You can translate tones into frequencies using

http://www.kitz.co.uk/adsl/adsl_technology.htm#frequencies

It is then a more difficult problem trying to discover what device(s) are injecting noise at those frequencies. E.g. low frequencies are frequently BBC Radio 4 - 198.xxx and there's not much you can do about that unless you can get a filter fitted.

Kind regards,
Walter

[Ezzer]

Incidentaly, dsl isn't necceceraly affectected by a transmission within its range of frequencys. Radio broad casts produce a type of noise which the dsl signal washes over.

It's a bit like the difference of a situation where your having a conversation with someone and in one senario you may have say gentle piano music playing in the backround. and another senario where you can have an annoying sound the same if not lower volume to the previous piano music.

1st senario you can hold your conversation with no distraction. the second even though the amount of interference may be the same or less it has a noteable interuption to your conversation.

As I understand it when snr/snrm is measured it's relative to the type of signal dsl is, there may be other emf sources around with similar or greater energys however it's not having an effect on the dsl signal.radio stations fall into this group. Its one of the problems of locating REIN with a radio. You may hear lots of sounds in the frequency range your looking at, but they may not have any effect with dsl 

Although saying this very occasionaly an rf3 filter (or its comercialy avalable plug in equivalent) can have a slight benifital effect on dsl dispite the fact it leaves the dsl frequencies alone and filters out at much lower frequencies. I belive this is because if this noise is having an effect then again its because its the right form of noise but at a harmonic a few orders down from the dsl signals affected

[jeffbb]

Hi

quote All i've done is follows....
1) With Router Login&Logout - Select DG834(G,GT) v1-4 and setup login stats page and login details
2) Within the telnet tab->Negear Setting - enable telnet (Netgear DG834(G,GT))

In the Netgear version box  have you selected 
Have you selected the the BROADCOM version ?
Regards Jeff

[hyeung]

Hi Hyeung,

Although all the pictures are different they are showing similar sets of data. What you are mainly looking for are those tones which are carrying zero or only a couple of bits.

You can translate tones into frequencies using

http://www.kitz.co.uk/adsl/adsl_technology.htm#frequencies

It is then a more difficult problem trying to discover what device(s) are injecting noise at those frequencies. E.g. low frequencies are frequently BBC Radio 4 - 198.xxx and there's not much you can do about that unless you can get a filter fitted.

Kind regards,
Walter

Hi,

Managed to get this routerstats working with my DG834PN finally!
Don't asked me why, but i decided to flash it with the latest firmware DG834PN_V1_03_39_DGTeam_0848.zip
After this, gave it another go and messed around with the settings.

Now i have the Bits/Tones, Summary, Rx Noise working much better now.

My connection was synced at 10Meg at around 14db SNR.....and it dropped not long ago; resyncin at 6.8Meg at 7db SNR.
Anyways, i managed to capture the Bits/Tones before the drop (i.e. at 10Meg) and then again after the drop (i.e. at 6.8Meg)
The graphs are attached...
Again, i'm not entirely sure about how to interpret all this.
It looks like a massive drop in the bits (buckets) in each of the tones...and from tone 344 onwards they no longer hold any bits. And also a drop in the SNR in each of the tones...Not sure what the wee dots are all about, something about bit swaps? but not sure how these relate to each of the lines or tones.
While the attentuation in each of the tones is unchanged.

I'm still none the wiser in what exactly this information could be used to help? Other than knowing exactly the tones or hence the frequencies that are being interferred with.

Can you advise?

Current Summary is:
Downstream
Noise Margin:     7.0   dB
Connection Rate:  6831  Kbps
Line Attenuation: 34.0  dB
Power:            1.5   dBm
Max Rate:         8372  Kbps
 
SF:               46952
SF Errors:        0
Reed Solomon:     3051930
RS Corrected:     30697
RS Un-Corrected:  0
HEC:              0
Errored Seconds:  177
Severe ES:        166
Interleave Depth: 32

UpStream
Noise Margin:     10.5  dB
Connection Rate:  765   Kbps
Line Attenuation: 17.1  dB
Power:            12.8  dBm
Max Rate:         1020  Kbps
 
SF:               45947
SF Errors:        1
Reed Solomon:     1244308
RS Corrected:     0
RS Un-Corrected:  0
HEC:              0
Errored Seconds:  1
Severe ES:        0
Interleave Depth: 8





[attachment deleted by admin]

[hyeung]

It would seem that theres an affect on the SNR across the whole range of bit tones. A sample of the bit tones before the SNR drop, during the SNR drop and after the SNR drop due to a resync to lower speed 6Meg.

Also had the radio on MW during this espisode....and the noise went from a quiet buzz to a very loud constant buzz.....I wasnt able to track it down as the same loud buzz is pratically everywhere in the flat?
Even went outside down the common block and out on the street....same loud buzz? So can't really tell where its coming from....

Oh btw, as suggested by Ezzer.....i did unplug the modem RJ11 cable and turned the router off.....tried moving the radio around the modem cable....and stil the same loud buzzing noise? Well the buzzing noise is pratically everywhere as i've mentioned.

What do u reckon? Based on this, definetly a REIN issue then? Any other ideas on narrowing it down?


[attachment deleted by admin]

[waltergmw]

Hi Hyeung,

Can you hear anything with the quiet line test 17070 ?

On your next BT engineer's visit take your modem down to the distribution box and get the engineer to connect your line there for you.
That would eleminate building wiring.
If successful try to run screened twisted pair preferably provided by BT O as a special measure, (@ Ezzer - can it be ordered?) or if not get a length of Cat 5e FTP installed ready for the BT engineer to connect in place of your existing cable. EDIT But only connect the drain wire to earth at one end.

http://www.cablemonkey.co.uk/acatalog/FTP_Solid_Cable.html
http://www.gogocables.co.uk/acatalog/Cat5e_FTP_Solid_Cable.html
http://www.cableuniverse.co.uk/catalog/cables/Shielded-Cat5e-FTP-Cable-100M-Roll.html

Kind regards,
Walter

[hyeung]

During these SNR falls, I have done the quiet test before and it appears to be quiet. So no indication of any problems with the line.

If an engineer will come out....then i'll try and request connecting the modem at the distribution box. I assume this you mean the distribution point internal to the property......and NOT the cabinet outside the property?
I'm thinking the connection sync speed and SNR will be the same as what i get from my main mastersocket.

Anyways got a couple of questions numbered below....

1)
When you talk about trying a screened twisted pair....Are you meaning the RJ11 cable between my modem and my mastersocket? If so, i believe i am already using such cable as we speak. Its a Belkin high speed modem cable which i believe is shielded and a twisted pair http://www.broadbandbuyer.co.uk/Shop/ShopDetail.asp?ProductID=4408

2)
Can you please advise on the results suggested from the attached bit tone graphs as queried in my previous posts?
I want to know if what we see there clearly suggests REIN? Or anything obvious from the graphs?


I must say that having had the radio tuned constantly at ~612kHZ thruout the day....I have clearly noticed a difference in noise when the SNR drop occurs. As i've mentioned the noise is a very loud buzz which seems to drown the usual noise of the router or ADSL signals?
It happend again this evening (SNR drop).....and i noticed that the noise was still very strong outside the property. I decided to tune into 621kHz MW in my car radio and noticed the same buzz noise. Whats intresting is that when i drive away from the street the noise gets weaker and then stops. So decided to drive around the street to investigate further.
What i found out was the buzzing noise was strong between one end of the building to the other end on the same street.....so once you passed the building, the noise stopped.
I even drove across the same 2 points but on the following street....no noise.
And once the SNR had recovered later than evening, when driving around the same street there was no further noise detected from the car radio on the same station.

So it would appear that the interference is coming from either our building OR the new development across from us on the same street. The start and end of our building lies in the same way as the new development.

3)
So, can you give me your thoughts so far on this?
 
4)
As the interference is so strong and pretty large in coverage i.e. the whole street from one end of the building to the next.
What are the possibile causes? I question if this could be caused by a single resident?


Assuming you guys also think that this is obviously a REIN issue thats recently developed - most likely with new residents moving in. Then how does one get this investigated?
I'm only asking because i'm unsure of what Skys intentions will be. They are already unwilling to proceed further with things due to the number of BT engineer visits (total of 4). All the changes carried out have obviously not made any difference. As of Friday, they clearly didnt want to do any more despite me requesting a REIN investigation should be followed up based upon my findings and recommendation from the last BT engineer.
I will get a call tommorrow evening on the outcome of this? But to be honest doesnt look promising.
Can this issue be taken up with Ofcom to investigate the REIN problem? Or is there any other ways of doing this assuming all fails with Sky?
I'm still pretty surprised and shock that Sky are playing it this way.....seeing i've been with them for several years and my connection has been fine since now. So clearly something faulty has developed. My connection as it stands is till dropping atleast twice a day and is alot slower than what i had before.

Plus its not as if i can hire someone to track down this problem and resolve it...there is no such service available. So what does one do if Sky don't budge? Also, its not as if i can move to another ISP as i'm sure the problem will still exist.

[waltergmw]

Hi Hyeung,

No, not the RJ11 cable but I was meaning to rewire from the internal BT distribution Point up into your flat (even if it was just a temporary cable up a stair well or out of a window). The idea was to prove whether your unshielded cable was picking up noise within the building rather than through crosstalk from the building to the street cabinet.
If the building is reasonably modern there should be a service shaft so that hopefully it would not be too difficult a job to install a proper cable if that cured the problem.

You seem to have done a very good REIN tracing job already. Are there any street lights etc. that stay on when there's detectable noise ?


I'm afraid you will need to be politely insistent and if necessary refer it right up to senior management within Sky to get this problem resolved.
You can change ISP and there are others who are significantly more tenacious than others, although quite reasonably they usually charge a little more for their better service.

I think Kitz has already said that it looks like REIN but I'll leve the Gurus to comment further if they can on your evidence.

Kind regards,
Walter

[hyeung]

Ah gotcha now....I supose like you say we could connect the modem up at the BT distribution point firstly with my laptop and see what kinda connection i get i.e. SNR and Sync speed.
If it gives me the full whack i.e. capped 10Meg and up'd SNR of 13-14....then its internal wring thats picking up the interference.

Well, no matter how you put it. I know for sure its definetly interference of some kind that was never there before....last few years. And only started as of June (Coincidence that its the same time when new residents move into the new development across the street).

But based on my investigation to date, the interference is pretty widespread (based on my last post). I am right to think that such interference can also affect the router directly and rather than via internal wiring that's feeding the router?

Or is it simply the fact that such interference can only be propgated via
1) the internal building wiring
2) the external wiring at the cabinet coming into the building


As of Friday, i had dicsussions with Sky ticket manger...and he's agreed to discuss with the relevant team leads.
He also agreed to pass on my findings with regards to the SNR graphs. Unfortunately, i haven't passed on any recent findings as of this weekend (with regards to the bit tone graphs and the radio interference that i've identified within our building and outside the street)

On Saturday, i also wrote a letter of complaint regarding this to their customer relations dept (recorded delivery)...and also sent this same letter to Skys CEO Mr Darroch via email.
As i'm not exactly convinced that i'll be guaranteed any progression of this matter from Fridays discussions?

The only ISPs availble to me are Sky, Be, O2 and BT. For LLU its only the first 3. My exchange is the glasgow south WSOU

Regarding my questions/evidence (bit tone graphs etc).....i would mind getting some further feedback on these.
Walter has covered 1. So answers to questions 2,3 and 4 would be apprecaited?

[waltergmw]

Hi Hyeung again,

Although not impossible that there's a direct effect upon the modem,** I believe most REIN problems interfere with the very small ADSL signals on the phone lines.

** As a last resort you might compare a 2Wire 2700HGV as that is enclosed in a sort of Faraday cage

You certainly seem to be firing a number of broadsides at Sky, so there's no harm in letting them know of this post and it would save you having to duplicate the pictures.

Kind regards,
Walter

[hyeung]

Walter,

Thanks for your input to date....you've been helpful with the suggestions  
Regarding the modem....i just have to hold off on that and see how things go. As i've already purchased a different router (Billion 7402NX), on the thinking that its one of the better ones which would help with this issue.

I'm currently using an old DG834PN with a custom firmware DGTeam. This has allowed me to use the routerstat functionality i.e. bit tone graphs etc
So i'll hold on to this for the now.

I guess the last and final thing they could try on the line is what you had suggested.....but at the moment i'm not sure how things are going to pan out with Sky. So i might not get this oppertunity  
However, on chance i get to try this and it dont work (mastersocket to Distribution box).... I'd assume the same would have to be done for the cable from the distribution box to the cabinet i.e. put a temp shielded wire in.

I am reluctant to pass on the other images (bit tone graphs), as technically,  i'm not sure exactly what these prove compared to the SNR graphs that i have already provided. I guess you can say that i'm not clued up on how you interpret these.  All i can see from the bit tone graphs is that the SNR across the tones have dropped during the problematic times. So i'd assume the SNR graphs really say the same thing.

So for the meantime, until the other gurus can help comment on this evidence and explain in layman terms....exactly what these tells us or suggest. Then i don't really see the point in passing it over to the ISP?
Which is why i've been asking the questions in my previous posts to use this a additional ammo in order to raise the matter further.

Many Thanks

[hyeung]

Hi,

Sky have agreed to pursue the matter further as i have convinced them of a possible REINs issue....based on the activities and evidence i have gathered. Not to mention that the last BT engineer suggested this as well.

They have passed this onto BT and are requesting a REIN investigation be undertaken.
I guess a letter to the CEO probably helped put things in the right direction as well.

The only annoying thing is that BT are playing awkward buggers.....they have said that their systems do not detail a pair quality test being undertaken? I have had several engineer visits, and i do recall that at least 2 of them have done such tests i.e. checking for split pairs etc
They indicate that to pass things on to REINs dept....all such criteria must be met. So looks like Skys hands are tied due to BTs awkwardness. So the engineer is going to do this come Saturday.

I'm not sure if it'll be worth requesting for the modem test at the distribution box during this time?


Anyways with regards to REIN i have some further questions:

1) As my issue is a highly related to REIN. If i assume that the source is a resident at this area. How does one exactly resolve this matter, does BT have any authority to do anything with such matters other than locate the source? Or do they need to pass to OfCom for action?

2) It is likely a lengthly process when OfCom get involved?

3) It is possible for me to contact OfCom directly on this broadband issue without involving a BT REIN engineer?
By simply detailing my symptoms of broadband dropouts caused be interference, and describe the radio tests carried out to prove a high possibility of REIN in the area; attaching any other evidence collated i.e. SNR and Bit
tone graphs.

Many thanks,
Hung