As a Milton Keynes resident you may have visited the Bradwell Abbey estate. There's a pleasant enough park with the remains of an old abbey. There's also a 1970's industrial estate. It's a stone's throw from the Concrete Cows and the KFC.

Good, we know where it is. You can even find it on a map!

However, when BT refer to Bradwell Abbey they mean a large area of Milton Keynes. They mean an area that's bounded by Bletchley, Stony Stratford, Wolverton, Newport Pagnell, and Woburn Sands. They do not mean the local grid square known as Bradwell Abbey.

BT's Bradwell Abbey telephone area is served by an exchange building in Fishermead. The building is marked on the City Atlas: it's on the south of the estate near the V8 and H7 grid roads.

The exchange is 4km from the estate called "Bradwell Abbey".

The upshot on this confusion is that some residents get despondent as they think they are too far away from Bradwell Abbey, while others get optimistic as they think they are closer than they really are!

BT's Shenley Church End telephone area is served by the exchange in Emerson Valley. The building is marked on the City Atlas: it's on the north of the estate near the V3 and H7 grid roads.

This confusion explains why Loughton is not close to the "Shenley Church End" exchange.

See above entry for Bradwell Abbey: it's similarly "misnamed".

BT have run in a 250 pair copper cable to Monkston, where we are currently served by TPON (Fibre Optic)

If you are a TPON resident and you request Broadband, BT will route your telephone connection via the new copper instead of the existing TPON.

There should be no noticeable difference to you, for example your phone number remains the same. For the engineer doing the work it will mean a bit of extra scrabbling around in the exchange and in the various roadside cabinets as the copper is connected and the existing "kerb to house" cable.

BT will still use the existing TPON - it works fine for most of the Monkston residents that do not need Broadband. Only residents requesting Broadband will be transferred to the new copper cables.

The new 250 pair cable is more than enough for the 80 or so residents waiting for Broadband.

[WRONG! Why did I say that? It's now May 2005, and the cable is used up! BT are due to have a new one run in by October.]

Monkston residents are successfully getting Broadband.

http://62.172.198.79/broadband1/where_i_live/campaigns/current_campaigns_search.asp

http://www.bt.com/broadband/

BT only support campaigns that help them get their telephone exchanges Broadband enabled. They do not promote campaigns such as ours: all seven local telephone exchanges in Milton Keynes are already Broadband enabled.

The reason that many of us cannot benefit from the Broadband service is the distance of the BT telephone exchanges from our homes. Although ADSL signals do work over a distance greater than 6km, BT has a service rule disallowing long distance connections. (BT increased the distance from 5.5km to 6km in September 2003.)

Milton Keynes is served by seven exchanges, not one. All seven of them are ADSL enabled.

Our problems are with the long route the telephone cables take.

See the above Why isn't your campaign listed on the BT website.

No, it does not perform a real-time test of the line. The site's answer comes from a database compiled from records of the various cable lengths and gauges that make up the line to your phone.

The process BT uses, and their reasoning, is described here. Lines are qualified as red (failure) amber (further checking required) or green (OK).

Any line that is close to the limit is tested further by an "special investigations" engineer.

Here's an attenuation table based on the BTm model at 300kHz for 1km length

No. A decibel dB is a logarithmic unit used to describe a ratio. It is a lot more convenient for engineers to add dB's than multiply ratios. dB's can describe very big ratios with numbers of modest size. (A power ratio of 1000000 is 60dB.)

BT use a cable model: a telephone line of 0.5mm copper, 1km long will loose 10.301 dB at 300kHz. A 5.5km cable of 0.5mm gauge will have a loss of about 55dB.

(See ESTI TS 101 388 V1.2.1 (2001-10))

It's a lot easier just to talk about distances in kilometres than attenuation levels in dBs.

This topic has grown somewhat - and now enjoys its own page. Our concerns with neighbours with broadband and retrospective disconnections are explored here.

The cable distance limit from the BT telephone exchange to your house is approximately 6km. It was 5.5km. BT announced the change to their planning rule on the 9th September 2003.

The new extended limit for broadband is based on 60dB of signal loss on the line (typical line length about 6km) The previous limit, 55dB, equates to approximately 5.5km line length.

[Source http://www.btplc.com/Mediacentre/Archivenewsreleases/2003/NR0339.htm]

See also.

BT are confident that the BT web online broadband checker is 98% accurate with phone numbers. Postcode checks are 80% accurate.

This was revealed in a meeting with BT February 2004.

The logic that the postcode checker uses is desperately simple:

1, Get punter's postcode.

2, See which telephone exchange serves the punter, and calculate the distance between the two "as the crow flies".

3, If the distance is less than 3km report a "green" optimistic message; between 3km and 4km report a more cautious "amber" message; over 4km report a very cautious "red" message.

There is no use of cabling information used in compiling the report.

Do not use the postcode checker: its results are not accurate!