Noise level

My line failed the test due to the noise on it being in excess of the 60db
limit. Does anyone know what the limit is for the 10km limit they are
testing.

the distance doesnt matter, with a signal to noise ratio of that, adsl just
wont work, sorry
"Richard Rollins" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> My line failed the test due to the noise on it being in excess of the 60db
> limit. Does anyone know what the limit is for the 10km limit they are
> testing.
>
>

"Richard Rollins" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)
> My line failed the test due to the noise on it being in excess of the
> 60db limit. Does anyone know what the limit is for the 10km limit
> they are testing.

There is no limit for the trial - they are trying everything to see what
works and what doesn't..

I would say the new limit will be at least 70dB.

Regards
Sunil

> "Richard Rollins" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
>> My line failed the test due to the noise on it being in excess of
>> the 60db limit. Does anyone know what the limit is for the 10km
>> limit they are testing.
"marky" <(E-Mail Removed)> wrote in message
news:cbsg6c$1le$(E-Mail Removed)
> the distance doesnt matter, with a signal to noise ratio of that,
> adsl just wont work, sorry

In excess of 60 db would be an exceptionally good signal to noise ratio
(lots of signal and very little noise).

However it is a high line loss (which is related to distance) and that is
why you may not be able to get ADSL.

--
Old Codger
e-mail use reply to field

What matters in politics is not what happens, but what you can make people
believe has happened. [Janet Daley 27/8/2003]

marky <(E-Mail Removed)> wrote:
> the distance doesnt matter, with a signal to noise ratio of that, adsl just
> wont work, sorry

<looks at current attenuation>

63.9dB.
Working well.
SNR of 11dB.

On Tue, 29 Jun 2004 18:30:57 +0100, in article
<(E-Mail Removed)> "Richard Rollins"
<(E-Mail Removed)> wrote:

> My line failed the test due to the noise on it being in excess of the 60db
> limit. Does anyone know what the limit is for the 10km limit they are
> testing.

You mean it failed the attenuation limit. As for the extended reach trial,
there is no set limit, but the results of the trial will be used to revise
the existing limits upward provided that the majority of participants get
good performance.

Generally, provided the signal:noise ratio is adequate the absolute
attenuation isn't a problem until the signal is sliding into the
irreducible noise floor due to thermal effects. But SNR can reduce if
noise is induced in an otherwise OK connection, my SNR margin can be as
high as 36dB, but sometimes it is in the 6-10dB region for short periods.
The modem copes, but if my loop attenuation were higher than 43.5dB it
would be more likely to cause problems when this happens.

--

Brian Morrison

please observe reply-to address

"Brian Morrison" <(E-Mail Removed)> wrote in message
news(E-Mail Removed)
>
> Generally, provided the signal:noise ratio is adequate the absolute
> attenuation isn't a problem until the signal is sliding into the
> irreducible noise floor due to thermal effects. But SNR can reduce if
> noise is induced in an otherwise OK connection, my SNR margin can be
> as high as 36dB, but sometimes it is in the 6-10dB region for short
> periods. The modem copes, but if my loop attenuation were higher than
> 43.5dB it would be more likely to cause problems when this happens.

My downstream attenuation is 52/53 dB. S/N is rarely above 10 dB, and I
have never seen it above 15 dB. Currently S/N is 6 dB. I do get periods
when sync will drop for very short intervals, sometimes annoyingly often,
but when the S/N is down at 5 or 6 dB the connection is usually as solid as
a rock.

--
Old Codger
e-mail use reply to field

What matters in politics is not what happens, but what you can make people
believe has happened. [Janet Daley 27/8/2003]

being a broadband engineer for BT, I was just pointing out that with a line
loss such as 60db, it will not be stable, the other guy that said he had 63
db, how do you know that,?.....we have various ways to test, but not any
available to the public.


"Sunil Sood" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> "Richard Rollins" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)
> > My line failed the test due to the noise on it being in excess of the
> > 60db limit. Does anyone know what the limit is for the 10km limit
> > they are testing.
>
> There is no limit for the trial - they are trying everything to see what
> works and what doesn't..
>
> I would say the new limit will be at least 70dB.
>
> Regards
> Sunil
>
>

marky <(E-Mail Removed)> wrote:
> being a broadband engineer for BT, I was just pointing out that with a line
> loss such as 60db, it will not be stable, the other guy that said he had 63
> db, how do you know that,?.....we have various ways to test, but not any
> available to the public.

I captured a BT engineer and have him tied down in my dungeon, as well
as assorted plumbers and other tradesmen.

Be warned, they are picky eaters, he turned his nose up at the Sky
engineer, eventually I had to provide Ketchup.

"Old Codger" <(E-Mail Removed)> wrote in message
news:CelEc.848$(E-Mail Removed)...
> "Brian Morrison" <(E-Mail Removed)> wrote in message
> news(E-Mail Removed)
> >
> > Generally, provided the signal:noise ratio is adequate the absolute
> > attenuation isn't a problem until the signal is sliding into the
> > irreducible noise floor due to thermal effects. But SNR can reduce if
> > noise is induced in an otherwise OK connection, my SNR margin can be
> > as high as 36dB, but sometimes it is in the 6-10dB region for short
> > periods. The modem copes, but if my loop attenuation were higher than
> > 43.5dB it would be more likely to cause problems when this happens.
>
> My downstream attenuation is 52/53 dB. S/N is rarely above 10 dB, and I
> have never seen it above 15 dB. Currently S/N is 6 dB. I do get periods
> when sync will drop for very short intervals, sometimes annoyingly often,
> but when the S/N is down at 5 or 6 dB the connection is usually as solid
as
> a rock.
>
> --


I use Solwise 715 routers and when I connect via telnet I can ask for ADSL
performance figures and this is what I see

2 Meg Plusnet connection been working fine for over 2 and a half years now


Login successful

--> adsl show perf
Downstream :
Noise Margin : 6.5 dB
Attenuation : 64.5 dB
Output Power : 19
Upstream :
Noise Margin : 8.5 dB
Attenuation : 31.5 dB
Output Power : 9

-->

2 Meg Plusnet connection been working fine for over 1 year now

Login successful

--> adsl show perf
Downstream :
Noise Margin : 7.0 dB
Attenuation : 63.5 dB
Output Power : 19
Upstream :
Noise Margin : 9.5 dB
Attenuation : 30.5 dB
Output Power : 9

-->

So if 60db is the maximum how the hell have I got 2 fully working 2 meg
connections well it ain't what you know its who you know


Are these figures bad then?

cheers for all replies