BT has released a new device that promises broadband customers a faster and more stable internet connection, by filtering out the electronic noise created by normal household items such as televisions, electrical wiring and lighting.

BT first mooted the device, known as the I-Plate, back in July, but announced on Wednesday that the device was now available to ISPs from BT Wholesale. However it warns that communication providers are expected to take time to start offering the I-Plate to their business and consumer customers.

ADSL connections have always been vulnerable to electronic noise. Speaking to Techworld, Ashley Pickering, principle engineer at BT's broadband Access and the man behind the I-Plate, said that the I-Plate is a combination of filtering and a self installable device.

"The majority of lines will benefit for the I-Plate for the filtering," he said. "A normal telephone line is a single wire made up of two wires. From the master socket, the pair of wires is carried around the house or building, carrying a telephone and broadband signal."

"However, in addition to this, a third wire generated at the master socket is also carried around the house," he explained. "This third wire was used to make old telephones (those with bell ringers) ring. It is a legacy line, but this third wire upsets the broadband carrying pair, as it increases the noise on the line."

According to Pickering, the I-Plate effectively filters the noise from inside the home or building, but also includes the ability to block noise (typically radio frequencies) from the entering the house in the first place. He confirmed that customers would still need micro filters on their telephone extensions, even after the I-Plate was installed.

"Yes you would, we are not changing the model there," he said. "You still need micro filters on extensions, as they are a telephony filter, which keeps the broadband signal from interfering with the telephony signal."

BT says the device is self installable, and doesn't need an engineer, but only works with the BT NTE 5 master socket, which is easily identified by the horizontal split in the face plate and the BT logo.

"It is easy to fit, simply unscrew the faceplate, do nothing with the wires," Pickering said. "Slip this device around wires, clip the I-Plate in place in the socket and then reassemble." He said it only takes a couple of minutes and most of the feedback BT has received had been very positive.

The carrier said the seven out of ten UK homes with a BT NTE 5 master socket are eligible for an I-Plate, and claimed that in a benchmark study of 36,000 lines, the device typically showed a speed increase of up to 1.5Mbit/s. Some lines showed speed improvements of as much as 4Mbit/s.

BT said that as well as boosting overall speeds, the I-Plate could improve the stability of the broadband connection, and can also extend the geographic reach of a broadband service by around 10dB, meaning that houses or businesses located some distance from their telephone exchange may receive an improved service, whilst others that were previously just beyond the reach of a broadband service, may now be able to do so.

Customers are advised to contact their ISP rather than BT Wholesale. Pricing has been mooted around the £10 ($17.75) to £12 mark, although some ISPs are expected to offer it free of charge.