BT BRAS Profile

[Rik]

But before you do anything else, Tina, check the attenuation of her line. Otherwise you may be chasing ghosts.

Given you say that phones are plugged directly into the other sockets, I'm guessing that she has a filtered faceplate, one socket for the phone one (smaller) one for the router. If this is not the case, it's probably her phones causing the problem, so, as has been suggested, unplug them all.

[T_M_D]

Hi Tina

Not necessarily, it depends on the route that her phone line takes to get to the exchange. For example, my house is about 100 yards from the exchange, as the crow flies, and yet my line is 1.5 miles long - it literally goes round the bypass and then comes back into town.
Simon

Oh right, thanks Simon. I will check it with BT tester. Thanks.

[Rik]

The tester won't help you, Tina, you need to get the information from the router.

[T_M_D]

OK.  You need a small portable radio with AM bands - not a DAB portable.  Switch it to Medium Wave and set the tuning to around 60/63 kHz.  Now all you should hear is white noise - some radio hams used to call it 'shash' - but you'll know it when you hear it.  Key is to not be able to hear any radio station, but a steady background 'rushing' sound. 

Now try moving the radio near an energy saving light bulb and the noise will increase dramatically.  This is the noise you are looking for.  Now if you move the radio round the house, you will pick up where the noise is that potentially will be picked up by you phone line and broadband kit.  Follow the phone line and see whether there are any areas where there is a significant increase in noise, which the line might be picking up.

It's not an exact science and won't necessarily tell you where the noise is coming from, but it will let you know it's there.  You can then take such action as you are able. 

Ok. Thanks. I will try other things first though before doing that.
HTH   

[T_M_D]

The tester won't help you, Tina, you need to get the information from the router.

Morning Rik,

oh yes, course. Will not having the router on initially for 10 days or so have stoped the router from syncing at the best speed?

[Rik]

No, the DLM is constantly monitoring the line, it will only have delayed the start of the training period, during which faults can't be reported to BT.

[nowster]

60/63kHz is well below the Long Wave band, never mind Medium Wave.

Extension wiring can cause major problems, especially if it's been done with flat cable (as in the cable used in phone to plug leads) or burglar alarm cable, rather than proper twisted pair phone cable or CAT5.

The "standard" test is to disconnect all extension wiring and test the router on the master socket located inside the main BT socket.

As others have said, you must use the stats provided by the router itself, and that the BRAS will not usually change upwards for 5 days after things have improved. (It might be possible for the ISP to request the profiling be reset, but I'm not sure on that point.)

[Tacitus]

60/63kHz is well below the Long Wave band, never mind Medium Wave.

My mistake it should be 600/630kHz - the markings on my old radio have almost gone and I wasn't thinking.  I still prefer the old days of 208 metres etc

[Rik]

I may weigh in kilos, but I have to convert to stones to know how heavy I am, Tac.

[Tacitus]

I may weigh in kilos, but I have to convert to stones to know how heavy I am, Tac.

When I was working on highway design, I had to mentally convert metres into feet in order to visualise the width of the carriageway....

[Rik]

Old habits and all that.

[MisterW]

The "standard" test is to disconnect all extension wiring and test the router on the master socket located inside the main BT socket.

That's what you need to do first!!, if the sync speed improves when plugged into the test socket then the problem is internal wiring and/or stuff thats plugged into it. If the sync speed doesn't improve then you need to look at the attenuation to see whether its similar to yours, if it is then its probably a line fault. If the attenuation is higher then ( as others have said ) it could be that the route taken from the exchange just makes the line a lot longer than yours and that its going to mean slower speeds I'm afraid.

Assuming the synch speed improves in the test socket, then we need to decide whether, as has been suggested, she has a filtered faceplate or not...
See this site for some good info on socket types http://www.kitz.co.uk/adsl/btsockets.htm
If its not a filtered faceplate then all the things plugged in ( except the router ) need to be via filters, that includes answer m/c, fax and especially a SKY box!!!
You might want to check out more info on troubleshooting on the kitz site http://www.kitz.co.uk/adsl/troubleshooting.htm and about possible ring wire issues http://www.kitz.co.uk/adsl/lowSNR.htm

Hope that helps

[Rik]

Or even:

http://www.idnetters.co.uk/forums/index.php?topic=1904.msg31528#msg31528

[T_M_D]

Right,

today I have discovered the following things:-

I was wrong about being on the same exchange as my friend - she is on the Thurnby exchange in Leicester which is LLU and I am on the Billesdon Exchange in Leicester which is non-LLU. I mistakenly thought that because when I inputted her telephone number into IDNet she could only get the same non-LLU package as mine and because she lives close to me that she was on the same exchange as I am. I now realise of course that this is not the case and that the reason she would get the same non-LLU package as me with IDNet is not because her exchange is non-LLU but is because IDNet is not in her exchange.

Her line attenuation is: 56.6db/31.5, Noise Margin 10.9db/19.0db. Downstream 1,504Kbps Upstream 448Kbps.

The modem cable and one phone extenstion cable (with a phone attached) was going in to the little adpater that has a socket for the phone and a socket for the modem - there was not an ADSL filter on  it, I have now fitted one. The BT socket is a twin one - there is nothing in the other socket, but I did test a phone in it and it is live.

The actual line from outside that feeds the internal BT sockets has some kind of twin splitter on it outside the house with a cable from one side of it feeding into the bedroom socket and a cable from the other side of it feeding into the hallway socket - when ringing in to the house a low-level consistent buzzing noise can be heard on both the bedroom phone and the hall phone. The phone in the hallway socket emits the buzzing, but it is not as loud as what can be heard on the bedroom phone. It isn't a crackle, the pitch does not go up and down, it is a constant low buzz, though some might describe it has a hum maybe.

Apparently, there was an issue with the phone line a few years before the house had broadband connected when the splitter was installed to feed the bedroom and hallway sockets and at that time my friend and her husband were charged for the fault to be rectified, though some time later, after they contested it, the charge was reimbursed when it was proven that the fault was not an internal wiring one.

I am thinking that this low buzzing noise indicates a noise problem that is affecting the broadband...? I remember something on here about running some kind of 'BT noise test' on the line? Should this be my next course of action or does the fact that it can be clearly heard on both the bedroom phone and the hallway phone clearly indicate that the fault is a noisy line?

One other thing, I did a ping.test and the line was reported as having an 'A' rating - is this at odds with the buzzing noise on the line?

[Steve]

Right,

today I have discovered the following things:-

I was wrong about being on the same exchange as my friend - she is on the Thurnby exchange in Leicester which is LLU and I am on the Billesdon Exchange in Leicester which is non-LLU. I mistakenly thought that because when I inputted her telephone number into IDNet she could only get the same non-LLU package as mine and because she lives close to me that she was on the same exchange as I am. I now realise of course that this is not the case and that the reason she would get the same non-LLU package as me with IDNet is not because her exchange is non-LLU but is because IDNet is not in her exchange.

IDNet works off the BT backbone it is non LLU and for the home user will provide ADSLmax and WBC 21CN,both BT wholesale products depending on the local exchange capabilities.


The downstream attenuation of 56db puts her about 4km from the exchange with a potential maximum sync on adslmax of ~3500 The d/s noise margin of 11 shows that it has been raised from the default 6 to 12 to overcome instabilty/noise on the line. As the noise margin is raised the downstream sync will fall.

If you want to try further you've got to attach the modem into the test port on the master  socket and see if there is any improvement in the stats

[T_M_D]

IDNet works off the BT backbone it is non LLU and for the home user will provide ADSLmax and WBC 21CN,both BT wholesale products depending on the local exchange capabilities.

Ok Steve, thanks for clearing that up for me, I didn't realise that.

[Steve]

A good read.

http://www.idnetters.co.uk/forums/index.php/topic,1904.msg31528.html#msg31528

[T_M_D]

If you want to try further you've got to attach the modem into the test port on the master  socket and see if there is any improvement in the stats

OK, I will do that. Thanks. What about the noise that can be clearly heard on the phones plugged in to the two sockets (hallway and bedroom) when receiving an incoming call? Can that noise be down to the internal wiring then rather than a BT line fault?

[Rik]

It could be down to almost anything, Tina. I don't like the sound of that splitter, it would suggest that the other two sockets don't have a master, or there are two master sockets on the line. Either way, I think you need to fit filters to any socket in use, despite having the filtered faceplate.

[Steve]

I am not sure its a filtered faceplate it might just be a double socket.

[Rik]

A picture would certainly help.

[T_M_D]

It could be down to almost anything, Tina. I don't like the sound of that splitter, it would suggest that the other two sockets don't have a master, or there are two master sockets on the line. Either way, I think you need to fit filters to any socket in use, despite having the filtered faceplate.

Hi Rik. My feeling is that the splitter feeding the two sockets that both have the noise on when receiving an incoming call is somehow responsible. My friend's husband said something about a cable with the splitter connected to it coming up through the ground outside the house from the main line then one piece of cable from one part of the splitter going up the wall in to the bedroom socket and the cable in the other part of the splitter feeding into the hallway socket. I couldn't take a look as it was dark and late when I found out about it, but I am there doing work on Monday so I will check it out.

I will have a good look at all the sockets to try and establish what type each is, I have though made sure anyway that there is an ADSL filter in every socket where there is either a phone plugged directly into it or where an extension lead is plugged in with a phone at the end of it.

The socket in the dining room, where the BT hub is connected is a twin telephone socket - both sockets are live. Only one of the sockets is in use, there was a little BT adapter plugged into the socket to allow for the telephone and hub connection - there wasn't an ADSL filter in there, but there is now.

I will use the new laptop, connected with the LAN cable to the hub to connect it directly to the test socket (I am assuming it is the hall socket). Luckily she has the new laptop I can use as otherwise I would have had to move the PC out into the hallway in order to reach the socket as the hub is currently connected to the PC in the dining room.

Once connected, I assume I then need to perform a BT speed test and check the modem stats - what will change (if anything) when connecting it to the master socket? Will I see an increased download speed from the consistent 0.97Mb? Will it be the IP profile that increases (currently 1000Kbps)? Is the DSL Connection Rate the bRAS or is it the IP Profile that is the bRAS? I Am trying to get my head around the whole subject and I am trying to learn from the available info (yours Rik) and Kitz whenever I get the chance, but I greatly appreciate all direct help here too as I am struggling with it all a bit (available time for studying all the information is my main constraint).

If I discover the socket in the bedroom is also a master socket - do I need to set up the laptop and hub from that socket as well? I always assumed that it was only possible to have one master socket when there is one phone line, but if BT fit a socket in another room is that also a master socket?

[Rik]

Hi Tina

The significant figures are the sync speed, noise margin and attenuation immediately after the router achieves sync. This tells us the 'raw' state of the line. Profiles were originally called bRAS profiles, but became IP profiles, they are one and the same thing. The profile is decided by two things, primarily the sync speed on the line, but also by the error count (which can be used by DLM to force a re-sync).

The only way to check that there is a single master socket it to have a look at the back of each faceplate. The master has a large capacitor and a lightning surge protector. There should be only one like that for the circuit.

If  things improve, you will usually see a higher sync speed initially. Over time, that can translate to a reduced target noise margin and yet further speed. The BT test is only really necessary to check throughput against profile and to establish what the profile is. It's directly related to sync speed, but will not change immediately.

If you get a higher sync, post the figure and I'll tell you what the profile should rise to, though it can take five days to do so.

[T_M_D]

Hi Tina

The significant figures are the sync speed, noise margin and attenuation immediately after the router achieves sync. This tells us the 'raw' state of the line. Profiles were originally called bRAS profiles, but became IP profiles, they are one and the same thing. The profile is decided by two things, primarily the sync speed on the line, but also by the error count (which can be used by DLM to force a re-sync).

The only way to check that there is a single master socket it to have a look at the back of each faceplate. The master has a large capacitor and a lightning surge protector. There should be only one like that for the circuit.

If  things improve, you will usually see a higher sync speed initially. Over time, that can translate to a reduced target noise margin and yet further speed. The BT test is only really necessary to check throughput against profile and to establish what the profile is. It's directly related to sync speed, but will not change immediately.

If you get a higher sync, post the figure and I'll tell you what the profile should rise to, though it can take five days to do so.

Thanks for all this Rik. I am puzzled though at what point would I be able to conclude that there might actually be a line fault that can only be resolved by contacting BT and reporting it to them for them to fix? That will ultimately be the only solution that will eventually fix things if there is a line fault, but I just can't work out from everthing discussed how I categorically prove it is/isn't a line fault and when/if I should bounce it to BT?

When I had noise on my line that was crackling during a call as well as when listening to the dialling tone (my friend's is a low-level hum/buzz) I rang and reported it becuase I thought it was a fault and the automatic line test BT ran on the line found that it was a line fault and eventually an engineer came out. The problem affected the whole village and turned out to be waterlogged underground cabling and the BT engineer's testing equipment also picked up something to do with 'unbalanced lines/cables' so my problem was identified and eventually resolved by ringing BT in the first place. Should I have rung BT in the first place do you think, regarding the buzzing/humming on my friend's line before I do all this diagnosis? Tina.

[Rik]

It depends on the volume, Tina. All lines have some background noise, either a hum or a hiss.