Date   : Sun, 21 Mar 2010 09:56:39 +0000
From   : darren.grant@... (Darren Grant)
Subject: [OT] ADSL capabilities

On 21 Mar 2010, at 07:25, Mike Tomlinson wrote:
> 
> A 4132Kbps sync sounds reasonable given your line length and attenuation
> figures. You could try a BT iPlate (I know you're in France, but it's
> all the same) and borrow a few different routers to try.  Some are
> better at negotiating a higher sync speed than others.  Changing from a
> Siemens router which sync's at about 7052Kbps to a Netgear DG834GT (2
> quid on ebay) got me an instant increase to 8032Kbps and it hasn't
> changed since.  I'm 2.5kn from the exchange, in an old residential area.

The iPlate would be utterly useless as the french do not use a 3 wire system. 
The BT iPlate is a very basic device that simply isolates the ring wire. 
In UK telephone wiring it is a 2 wire system all the way to the house where 
a capacitor is used in the master socket to provide a separate ring signal, 
making it a 3 wire system.  Because this capacitor is in the master socket
before any ADSL filters the ADSL signal goes down the ring wire and causes
an imbalance on the otherwise balanced ADSL signal.

The iPlate is designed for luddites who are scared of wires, by fitting 
the iPlate between the back box and the faceplate on an NTE-5 master socket 
the ring wire is isolated by using a simple RF choke. For those of us that
are not scared of wires this same thing can be achieved by removing the ring
wire on terminal number 3 for Free !

The best way however is to optimise your broadband is to fit a filtered faceplate
so that the ADSL signal is filtered at the master socket so it doesn't have
to travel through all of the extension wiring that is often not twisted pair.