Mark Rogers wrote:

Chris G wrote:

...

It's a BT "line improver" isn't it? I seem to remember it being greeted with some skepticism by gurus but that they changed their minds and that it really *does* improve speed quite often.

Here you go:-

http://www.productsandservices.bt.com/consumerProducts/displayTopic.do?topic...

"BT Broadband Accelerator" is BT's new name for the I-Plate

I know a little about I-Plate (ie that it exists); but the customer was quite clear about this "T-Bar" thing and I've never heard the I-Plate called by that name. (As I understand it, the I-Plate just disconnects the ring capacitor doesn't it?)

Sort of,

the i-plate disconnects the ring wire which is wired from the master sockets ring capacitor to other slave extensions in the house and I think it may also provide some additional filtering. The ring wire is a legacy thing from the days of REN numbers on phones where an additional ring voltage was needed to power the ring sounders in phones (back from them being a bell but some "electronic" ringers needed it too). This wire is redundant on modern telephones and therefore acts as a open ended pickup collecting EMI from other things in the house (and from the line itself) adding noise to the line.

As Nev states, simply cutting the wire at all sockets will have the same effect but the i-plate is a consumer friendly way of achieving much the same thing without having to resort to the wire snips (and the resultant support and engineer visits if "ordinary" people were asked to do this)*

However still the optimum way to operate ADSL is to filter off the ADSL with the original BT splitter faceplate at the master socket and run a separate (ADSL only) pair up to your modem/router. So those that had the original BT engineer installation ADSL service will already have the masterplate splitter as this is how the first ADSL installations were performed in the UK. People like me with this setup will have nothing to gain from the i-plate.

Effects of doing this are quite varied and dependent on the state/volume of extension wiring in the house and the quality of the ADSL service to begin with, I have been cutting that wire as a matter of course for several years now and have seen everything from no effect at all to ADSL that wouldn't even sync without this being done.

* Disclaimer AFAIK the situation is still that you aren't supposed to do this on the master socket yourself, but I don't think there is any penalty beyond getting charged for a call out should you introduce a fault.