BT launched the I-Plate last week (the 'I' stands for 'Interstitial') aimed at residential users who have a Network Termination Equipment 5 (NTE5) master socket through which their phone calls and broadband connection travel.

The claimed benefits of the device are increased throughput and more stable broadband connections.

This relatively simple box aims to reduce interference on the line, giving a better signal-to-noise (SNR) ratio on ADSL broadband connections.

The main culprit for interference on NTE5 master sockets is the so-called 'bell' or ring wire, which causes noise on your phone lines and reduces the SNR.

Originally the bell wire allowed bells to ring on older phones, unlike new phones which have the ring feature built-in. So the bell wire is redundant, but having BT come round to all residential customers and excise the wire would be expensive.

The other cause of reduced SNR could be interference picked up by the main twisted pair lines from your phone to the master socket. Radio frequency interference from other household appliances like TVs, and having mains wires close to your phone lines, could also be contributors.

The first thing for users to do is to 'baseline' their broadband connection to check the current throughput, and then to determine what they should be getting.

Putting your postcode into the Exchange checker on the Samknows website should give you the location of your local exchange and its distance from your home.

Our nearest exchange is just under a kilometre away, and we currently get a maximum download speed of around 13Mbit/s from our Be ADSL2+ (24Mbit/s) connection.

We got hold of an I-Plate from BT and 'installed' it on an NTE5 socket at our Computing & IT Week Labs branch office in Tottenham.

The NTE5 socket has a split faceplate and removing the two screws from the bottom half and gently removing it brought quite a surprise. Apart from the large amount of crud and dust residing behind the plate, there was a piece of sheathed cable wired to a few small connectors - but attached to nothing else.

Presumably the last owner was fairly clued in and had had the bell wire removed, or had done it themselves, although apparently it's illegal to mess around with the NTE5 wiring yourself. Fitting an I-Plate does not require customers to do any rewiring.

What most users should see is a wire attached to the faceplate they have just removed. This wire needs to be threaded through the gap in the I-Plate, and then the I-Plate is screwed to where the old faceplate was, and the old faceplate then screwed into place over the I-Plate.

This should take a couple of minutes to do. We pulled off the upper half of the faceplate just to confirm that the bell wire had indeed been removed, which it had.

Did we get a speed increase? It was hard to tell immediately, but may become apparent in the future. Users who have a bell wire connected should see some improvement and BT claims that 1.5Mbit/s faster connections are typical, with some users in BT's pre-launch trial seeing a 4Mbit/s improvement.

What this could mean is that, if enough users shell out £10 for an I-Plate and do get the claimed speed increase, there could be a significant increase in data traffic running over the network.

That means more backhauled data, and consequently more cash for BT, as ISPs may need to cough up extra for BT backhauling that data.

So the I-Plate could be a win for residential customers, and a 'nice little earner' for BT, as Minder's Arthur Daley would say.