I've got a lot of assorted inductors/... here.
My existing filter isn't quite cutting it (9dB SNR loss on inserting
a DECT/analogue cordless phone (oddly, both the wired phones I tried
were -0.2dB).

Can anyone point me at some filter designs, or the specs for them?

On 27 Jun 2005 23:49:43 GMT, Ian Stirling <root@mauve.demon.co.uk>
wrote:

the specs are in the G.dmt standard, dslforum.org or the like.

BT's SIN at www.sinet.bt.com has extracts and various impedance
requirements. SIN 346.

http://www.adslnation.com/support/filters.php may be interesting.

the dodgy phone will have to go :-)

Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali

AOL - the unlimited ISP of choice for heavy downloaders.

Phil Thompson <phil.thompson@spamcop.net> wrote:
Thanks.
Unfortunately, the dodgy phone won't have to go, I'll have to get it
filtered adequately.
I'll have to put the scope on it to see if it's outputting any obvious
crap.

Ian Stirling wrote:
Not wishing to rain on your parade, but I hope you are aware that connecting
non-BT approved equipment (in this case your DIY filters) to their network
is subject to prosecution and a *HEFTY* fine if/when they find out
--
paul.g.king@theobviousdsl.pipex.com
Reply address is spamtrapped. Remove theobvious for valid e-mail address

"Paul King" <paul.g.king@theobviousdsl.pipex.com> wrote in message
news:W_idnXWR8vmqCVzfRVnygA@pipex.net...
: Ian Stirling wrote:
: > Phil Thompson <phil.thompson@spamcop.net> wrote:
: >> On 27 Jun 2005 23:49:43 GMT, Ian Stirling <root@mauve.demon.co.uk>
: >> wrote:
: >>
: >>> Can anyone point me at some filter designs, or the specs for them?
: >>
: >> the specs are in the G.dmt standard, dslforum.org or the like.
: >>
: >> BT's SIN at www.sinet.bt.com has extracts and various impedance
: >> requirements. SIN 346.
: >>
: >> http://www.adslnation.com/support/filters.php may be interesting.
: >>
: >> the dodgy phone will have to go :-)
: >
: > Thanks.
: > Unfortunately, the dodgy phone won't have to go, I'll have to get it
: > filtered adequately.
: > I'll have to put the scope on it to see if it's outputting any obvious
: > crap.
:
: Not wishing to rain on your parade, but I hope you are aware that
connecting
: non-BT approved equipment (in this case your DIY filters) to their network
: is subject to prosecution and a *HEFTY* fine if/when they find out
: --
: paul.g.king@theobviousdsl.pipex.com
: Reply address is spamtrapped. Remove theobvious for valid e-mail address
:
:

I was of the understanding that your side of the wall is your and not their
network,ie no need for BT approval.

Chris
kick-butt.co.uk

On Tue, 28 Jun 2005 19:25:43 +0100,it is alleged that "Joker7"
<sat_ring@hotmail.com> spake thusly in uk.telecom.broadband:

<snip>

Technically anything connected to any phone jack that has access to an
outside line in the UK is "directly or indirectly connected to a
public telecommunications system" and therefore should have BABT
approval (note, BABT= British Approvals Board for Telecommunications
and is not part of BT). However, how good their enforcement is I don't
know, I can't imagine them wasting the money in tracking you down for
using a homemade and well designed filter or indeed any piece of well
designed equipment.

OTOH, if you were to build a device that had a failure mode consisting
of connecting the telephone line to 240 volts, (think Arthur Daley
special imports), they probably _would_ expend the resources to track
and prosecute, after the first phone company employee got hurt.

--
There is not the slightest indication that nuclear energy will
ever be obtainable. It would mean that the atom would have to
be shattered at will.
- Albert Einstein, 1932

"Ian Stirling" <root@mauve.demon.co.uk> wrote in message
news:42c09097$0$2046$ed2e19e4@ptn-nntp-reader04.plus.net...
My phone causes the ADSL to drop when it rings. I've fitted a second filter
in series and that's solved the problem.

Chip <chipmunk_1000@excite.com> wrote:
In theory, you require BABT approved cable clips, the way the regulations
are worded.
And indeed I suspect the number of prosecutions for using equipment
marked specifically as not to be connected to the BT network closely approaches
0.

Ian Stirling wrote:
But the charges raised by BT engineers significantly higher after they've
been called in to investigate why the line isn't working properly...

kraftee <kraftee@spamoff&die> wrote:
Which is why it'd be removed, before phoning them.

Ian Stirling wrote:
If only this was always true......

kraftee <kraftee@spamoff&die> wrote:
And if only it was possible for users to do it the right way - I'd have
liked to purchase a filter to plug into the NTE5, rather than one
that sticks out, and gets kicked by passers by, from the engineer that
came to remove my HH box and fit ADSL, but nope.

Ian Stirling wrote:
If you're talking about a SSFP (faceplate filter) it is possible to buy them
on the net (for some reason Claranet springs to mind but if you wait long
enough someone will come along with the correct site)...

As for users doing it the right way, I won't tell you about the alarm
engineer who fitted a hardwired filter between the feed & the NTE5 yet left
the alarm connected to the block 80b unfiltered, oops I just have.......

kraftee <kraftee@spamoff&die> wrote:
I think you are talking about clarity.it.
Also available from solwise.

Oh dear...

On 30 Jun 2005 18:50:37 GMT, Ian Stirling <root@mauve.demon.co.uk>
wrote:

www.clarity.it (yes, .it, but they are in the UK).
Just received it this morning. Looks nice enough.
or
http://www.solwise.co.uk/

Lorenz

On Thu, 30 Jun 2005 20:13:26 +0100, "kraftee" <kraftee@spamoff&die>
wrote:

www.clarity.it
www.adslnation.com

and others.

As well as the SSFP you can also get filtered sockets for extensions.

Phil
--
Tiscali - dialup speeds at Broadband prices, see
http://bbs.adslguide.org.uk/postlist...&Board=tiscali

AOL - the unlimited ISP of choice for heavy downloaders.

Hello,


Telcommunications devices used in the UK device don't need BABT
approval these days as it has been replaced by the European R&TTE
directive.

Kris.

On Sun, 03 Jul 2005 15:59:00 +0100,it is alleged that Kris Shaw
<qr5wh2r02@sneakemail.com> spake thusly in uk.telecom.broadband:

Interesting, I shall have to google for this, it sounds useful. I am
kind of glad that it's not necessary to comply with BABT requirements
anymore, they'd find my RJ11 phone jacks to be 'unusual' here in the
UK, although they'd be fine in Eire <g>.

--
This .signature has been hijacked by the Shellfish Liberation Army.
Please remain clam.

"Chip" <chipmunk_1000@excite.com> wrote in message
"Telcommunications devices used in the UK device don't need BABT approval
these days as it has been replaced by the European R&TTE directive."

I wonder then BT's policy would be if by adding something 'home brew' you
assisted the conduction of lightning? Just a thought.......

On Sun, 3 Jul 2005 18:04:14 +0100,it is alleged that "Steve Lispcombe"
<ping@pong.com> spake thusly in uk.telecom.broadband:

About the only way I could see that happening is if you earthed both
wires of the line pair, which come to think of it, most real
protectors[1] do this anyway in the event of a strike.

[1] as opposed to the Gas discharge tube in the master socket, which
so far as I can tell is purely there to short circuit the line in the
event of a power contact, such as some twit connecting a 13amp plug to
the phone cord, thus protecting BT's equipment. Something that small
isn't going to do anything serious to lightning.

--
"I think computer viruses should count as life. I think it says something
about human nature that the only form of life we have created so far is
purely destructive. We've created life in our own image." - Stephen Hawking