Howard Neil wrote:
So am I! A friend has a similar problem. The problem he has is the external
bell is wired directly into the BT side of the NTE5 and in theory he is not
allowed to alter it. The bell was installed thirty-five years ago by BT or
possibly it was still the Post Office then. My advice to him was to go ahead
and alter it regardless. He is going to fit a replacement face plate and
connect the bell wiring to the filtered terminals. You can get one here.

http://www.solwise.co.uk/adsl_splitters.htm


Peter Crosland

Peter Crosland wrote:
Thanks for the link.


--
Howard Neil

I shoudn't lose too much sleep over this.
Line conditions can and do change.


--
Graham

%Profound_observation%

"Jones" <noman@noaddy.co.uk> wrote in message
news:gp2024p9s7itcv5kmbjb1kj3rlsuhj5u1r@4ax.com...
What are you whitering on about Jonesy;
and anyway, didn't all those abductees come
*back for good?*
--
Graham

%Profound_observation%

What often happens is the thing works just in the balance. Then one day
something comes along to change the noise figures on the line. Perhaps
another DSL customer ends up in the same cable from the exchange, a line
changes its characteristics or perhaps new RF interference springs up
locally. It just tips the balance to stop the circuit, which was tolerant
before, from working. Playing with bell wires helps to reduce the loss
and brings the karma back. It is very dull as explanations go, but it
pretty much covers it.

External bells tend to suffer low-insulation across the pair and to earth
as time goes by. IIRC the impedance to start with is not fantastic either.

Christian wrote:
Thank you for that explanation. It's the only one I've got so I will go
with that. I hate it when things happen without a plausible explanation.
Not knowing why something has happened means it can happen again without
me being able to stop it.

--
Howard Neil

External bells generally are an inductive winding on an iron
core, at the above audio frequencies the impedance will rise,
which is why it probably worked without a filter. They
are however low impedance to start with and therefore
heavily load the line, so you were probably just marginal.
Todays extension ringers tend to be piezo transducer
based and don't load the line so heavily.
I have an old solenoid extension ringer which when
connected on the filtered phone leg drops me from
3Mbps down to 2Mbps ADSL.

Howard Neil wrote:
Sorry I'm late in getting back to you, & probably this has
already been pointed out to you.......the external extension
bell is not a compatable product (with DSL)

The only way you can have both working properly is to fit a
SSFP/faceplate filter (same thing different language).
Consider the fact that it did work as a lucky exception, but
getting a new one will probably cause you just as much
grieve.

The problem is at DSL frequencies the bell acts as a full
loop connection between the bell circuit & one leg of your
speach pair causing the nicely balanced speach circuit
(hopefully) to go wildely out of balance (& out the window
goes your DSL service).

Dave Saville wrote:
Unfortunately your idea, in case will not work as external
bells (as fitted in the days of BT/Brittish Telecom/post
office telephones etc, Openreach won't fit them normally
now) are hard wired & so the only filtering which can be
used on them is of the faceplate variety appropiately fitted

kraftee wrote:

Thanks for your reply. I think I have now solved the problem by deciding
to dispense with the external bell and rely on DECT. Your explanation is
most welcome, though.

--
Howard Neil