BT Engineers please help..

Sorry for the long post, please bear with me.

I have a problem with my broadband, I'm certain it's a line or exchange
problem but would appreciate some input from the BT engineers who pop up
here every now and then as well as the other knowledgeable people here.

For weeks I've had a line issue when and for a while after it rains.
Crackling, hissing and buzzing, causing the sync speed to drop and
making voice calls difficult.

Today I had my fourth visit from a BT engineer for this fault, he hooked
up his Hawk, went outside, climbed the pole, went to the cabinet down
the road and apparently changed me to another pair and spent ages doing
much more than any of the other engineers did (not complaining about
them at all, it's an intermittent fault).

The line is now silent until I connect one of my routers at the test
socket (to isolate all my internal wiring) and it syncs, I then get
horrendous crackling and hissing noises until a couple of seconds after
I physically disconnect the router (I.E. the noises are on the line, not
created by my router).

I've already replaced my BT faceplate filter with a brand new BT MF50
and I've also tried a brand new Zyxel filter so I know it's not my
filters.

Long and short, everything on my side of the deal has been replaced or
swap tested.

It seems a little odd to me that the crackling only occurs when there's
a synced router on the line, what changes on a line/at the exchange when
there's a router on it that might make this occur and what do I say to
get an engineer to check it out?

--
Clint Sharp

"Clint Sharp" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Sorry for the long post, please bear with me.
>
> I have a problem with my broadband, I'm certain it's a line or exchange
> problem but would appreciate some input from the BT engineers who pop up
> here every now and then as well as the other knowledgeable people here.
>
> For weeks I've had a line issue when and for a while after it rains.
> Crackling, hissing and buzzing, causing the sync speed to drop and making
> voice calls difficult.
>
> Today I had my fourth visit from a BT engineer for this fault, he hooked
> up his Hawk, went outside, climbed the pole, went to the cabinet down the
> road and apparently changed me to another pair and spent ages doing much
> more than any of the other engineers did (not complaining about them at
> all, it's an intermittent fault).
>
> The line is now silent until I connect one of my routers at the test
> socket (to isolate all my internal wiring) and it syncs, I then get
> horrendous crackling and hissing noises until a couple of seconds after I
> physically disconnect the router (I.E. the noises are on the line, not
> created by my router).
>
> I've already replaced my BT faceplate filter with a brand new BT MF50 and
> I've also tried a brand new Zyxel filter so I know it's not my filters.
>
> Long and short, everything on my side of the deal has been replaced or
> swap tested.
>
> It seems a little odd to me that the crackling only occurs when there's a
> synced router on the line, what changes on a line/at the exchange when
> there's a router on it that might make this occur and what do I say to get
> an engineer to check it out?
>
> --
> Clint Sharp
The noise is the signal from the DSLAM, it goes to sleep
about a second after it loses the signal from your router.

When your router was connected to the test socket,
I presume it was via the Zyxel filter, and the phone you
were monotoring the line with was plugged into the phone side
of that filter?

--
Graham.

%Profound_observation%

Ted wrote:

> Clint Sharp <(E-Mail Removed)> wrote:
>
> > *From:* Clint Sharp <(E-Mail Removed)>
> > *Date:* Sat, 22 Nov 2008 00:30:28 +0000
> >
> > Sorry for the long post, please bear with me.
> >
> > I have a problem with my broadband, I'm certain it's a line or
> > exchange problem but would appreciate some input from the BT
> > engineers who pop up here every now and then as well as the other
> > knowledgeable people here.
> >
> > For weeks I've had a line issue when and for a while after it rains.
> > Crackling, hissing and buzzing, causing the sync speed to drop and
> > making voice calls difficult.
> >
> > Today I had my fourth visit from a BT engineer for this fault, he
> > hooked up his Hawk, went outside, climbed the pole, went to the
> > cabinet down the road and apparently changed me to another pair and
> > spent ages doing much more than any of the other engineers did (not
> > complaining about them at all, it's an intermittent fault).
> >
> > The line is now silent until I connect one of my routers at the test
> > socket (to isolate all my internal wiring) and it syncs, I then get
> > horrendous crackling and hissing noises until a couple of seconds
> > after I physically disconnect the router (I.E. the noises are on the
> > line, not created by my router).
> >
> > I've already replaced my BT faceplate filter with a brand new BT MF50
> > and I've also tried a brand new Zyxel filter so I know it's not my
> > filters.
> >
> > Long and short, everything on my side of the deal has been replaced
> > or swap tested.
> >
> > It seems a little odd to me that the crackling only occurs when
> > there's a synced router on the line, what changes on a line/at the
> > exchange when there's a router on it that might make this occur and
> > what do I say to get an engineer to check it out?
>
>
> I had this exact same problem a while ago.
> It was caused by a High Resistance (i.e. corroded) connection. When the ADSL signal
> is present, the corroded connection acts as a diode rectifier and produces audible
> noise from the "RF" ADSL signal.

That makes 100% technical sense.


> Another problem with this fault was that the noise would stop for a while if
> someone rang the line, or if BT did a line check.

Because there's DC flowing in the line then ! The 'diode' conducts and stops
rectifying, since the voice signal is modulated DC not AC.


> BT/BTO blamed just about everything at one time or another. My Router, my phone, my
> PC, my extension wiring, etc. It was only finally fixed when a BT "ADSL" engineer
> gave me a different pair of wires from my house back to the street cabinet. Took
> over a year of complaining to get this done!
>
> The BT "POTS" engineers did not seem to understand the problem, taking the view
> that if the line was quiet with the router disconnected then the fault must be with
> the router (and then trying to charge me for a "no fault found" callout).
>
> You may need to be very persistent to get any action taken by BT with a fault like
> this.

Or know something about electricity and electronics.

Graham

On 22 Nov, 00:49, "Graham." <m...@privacy.net> wrote:
>
> The noise is the signal from the DSLAM, it goes to sleep
> about a second after it loses the signal from your router.

I realised that, the point I was trying to make was that the random
bursts of crackling disappear as well a second or so after the router
is disconnected and the DSLAM 'shuts up'.

It seems the DSLAM is making the crackling sound.

The SNR and Attenuation appear to be unaffected (but must be, I guess
the router isn't reporting quickly enough to show them changing)
>
> When your router was connected to the test socket,
> I presume it was via the Zyxel filter, and the phone you
> were monotoring the line with was plugged into the phone side
> of that filter?
Yes, I know the hissing noise is the DSL signal, it's a lot louder
than I'm used to though and there are random bursts of crackling (like
a noisy source select switch on an amplifier) when the router is
synced. I've tried three filters and four routers now to prove the
crackling is not my equipment, it's definitely on the line but only
when the DSLAM is active.
>
FWIW, I've been doing DSL installs and building networks for a number
of years now, I know my way around a router or two and the filters etc
but this seems an 'odd' fault to me, I've not seen one like it before
and it's on my home phone line just to make matters more annoying. I
know I have to report this to my ISP to get it resolved but I'm
looking for a heads up on what may be the cause so maybe I can get a
quick response.

> --
> Graham.
>
> %Profound_observation%- Hide quoted text -
>
> - Show quoted text -

--
Clint Sharp (posted via Google Groups, 'cause I'm not home at the
moment!

Ted chose to remove the x-post to ukt, so this gets messy unless I reinstate
it

As Ted and the other Graham have indicated, this noise is due probably to
"the rusty
bolt" effect,two dissimilar metals touching each other in moist conditions
giving rise to a non-linear junction, or diode effect.
All the DMT carriers mix together, and some of the demodulation products
are in the audio range and manifest themselves as white (actually pink)
noise.
As the mixing occurs before your filter there isn't much you can do.

Perhaps the best you can hope for is that the bad joint gets so bad
that it gives you a noisy line without your router connected.
then you can report it yourself as a voice fault.

I presume the Openreach visits you have had, have been at
the request of your ISP, in which case you have done quite well
so far. Many ISPs won't escalate this kind of fault and leave
you going round in circles.


--
Graham.

%Profound_observation%

In message <gg9c70$v5k$(E-Mail Removed)>, Graham. <(E-Mail Removed)>
writes
>Perhaps the best you can hope for is that the bad joint gets so bad
>that it gives you a noisy line without your router connected.
>then you can report it yourself as a voice fault.
Unfortunately it was bad enough without the router connected, that's how
I've managed to get openreach out to investigate without having my ISP
involved. The line is now perfect without the router attached.
>
>I presume the Openreach visits you have had, have been at
>the request of your ISP, in which case you have done quite well
>so far.
No, see above.
> Many ISPs won't escalate this kind of fault and leave
>you going round in circles.
Which is why I was hoping for a bit of advice on how to proceed. I'll
have to have a long chat with Demon on Monday and see how that goes, I
do still have a contact number in the UK so hopefully....
>
>

--
Clint Sharp

(E-Mail Removed) wrote:

> On 22 Nov, 00:49, "Graham." <m...@privacy.net> wrote:
> >
> > The noise is the signal from the DSLAM, it goes to sleep
> > about a second after it loses the signal from your router.
>
> I realised that, the point I was trying to make was that the random
> bursts of crackling disappear as well a second or so after the router
> is disconnected and the DSLAM 'shuts up'.
>
> It seems the DSLAM is making the crackling sound.

NO. Not in itself is isn't.

You have a line fault that doesn't show up on voice. It's simple
electronic theory as another poster and I have already explained

Graham

Eeyore wrote:
>
> (E-Mail Removed) wrote:
>
>> On 22 Nov, 00:49, "Graham." <m...@privacy.net> wrote:
>>> The noise is the signal from the DSLAM, it goes to sleep
>>> about a second after it loses the signal from your router.
>> I realised that, the point I was trying to make was that the random
>> bursts of crackling disappear as well a second or so after the router
>> is disconnected and the DSLAM 'shuts up'.
>>
>> It seems the DSLAM is making the crackling sound.
>
> NO. Not in itself is isn't.
>

Yes, its the combination of the d-slam AND the line fault that makes the
noise.

> You have a line fault that doesn't show up on voice. It's simple
> electronic theory as another poster and I have already explained
>
It probably does show up on voice, but not to a noticeable degree.

The key point is that 'a line that seems to work perfectly with the
router removed, does not necessarily imply a perfect line'

This is the point that BT need to have hammered into their brains.

I had a problem in that the line would mis-dial with the router connected.

That was solved by some contact cleaner on the router socket in the
microfilter. After I noticed that the problem seemed slightly related to
where the router was..




> Graham
>

The Natural Philosopher wrote:

> It probably does show up on voice, but not to a noticeable degree.
>
> The key point is that 'a line that seems to work perfectly with the
> router removed, does not necessarily imply a perfect line'
>
> This is the point that BT need to have hammered into their brains.
>
> I had a problem in that the line would mis-dial with the router connected.
>
> That was solved by some contact cleaner on the router socket in the
> microfilter. After I noticed that the problem seemed slightly related to
> where the router was..
>
>
>
>
>> Graham
>>

Probably a touch of rectified low, this will tend to make the ADSL
signal audible. Do BT still have SFIs? If so you need one of them to
look into the problem.


Steve H

PLH69 wrote:

> What phone are you using to test the line at the master "test/nte5a" socket?
> Not all phones work with ADSL.

Uh ? The test socket is normally used to check the ROUTER when there are
problems ! Phones should be connected through a filter.

Graham