BT has added two rural districts in Scotland to its trial of extended-reach ADSL broadband.
Fort William and Dingwall will join Milton Keynes as part of BT's trial to see whether ADSL can be stretched beyond the current 6km limits to 10km.
Milton Keynes was chosen because it has the highest percentage of people in the UK who are just beyond ADSL's current reach, but BT said it wanted to test some remote rural areas as well.
"Milton Keynes will give us the data we need but, because the aim is to see if ADSL can be used by remote areas, it was decided to add [Fort William and Dingwall] to the trials," a BT spokesman told vnunet.com.
A total of 23 ISPs, including BT Yahoo and PlusNet, have already signed up to take part in the project.
If the technology can work over longer distances it would open up ADSL services to a million more homes and businesses throughout the UK, according to BT estimates.
The Milton Keynes trial started on 1 June and up to 1,000 people can sign up. The Scottish trials will begin on 1 July and up to 100 volunteers in each of the districts are now being sought. Testing of the 512Kbps service will go on until the end of September.
Marco Potesta, marketing director at PlusNet, said in a statement: "We are pleased to be taking part in these additional trials that will help to further extend the reach of broadband.
"We have already seen a good response from people in the Milton Keynes area, with many positive comments from customers now enjoying high-speed broadband internet."
BT said will it will carry out line testing at each location. "We will be looking at the wiring in people's houses as this can play a significant part in signal degradation," the company said.
"There may be ways around this, such as simple modifications or using a wireless router."
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