Here you will find some of the most common reasons for being unable to have
ADSL and in some cases advice on what you can do about it:
Line length problem?
The maximum permitted line length for ADSL is 5.5km from your local
exchange. You can test your approximate line length by dialling (on your
intended ADSL line) "17070", The response will tell you the number of your
circuit. Then enter "3", then "1" (you ARE authorised, aren't you?), then "
2". If you then hang up, the test system will call you back and tell you the
approximate distance from your exchange.
If you have failed the ADSL "whoosh" test (see below) (or one of the other
line tests) - what can you do to make the best of a bad situation? It really
depends how far you want to go, but if you are determined to have ADSL if it
is remotely possible, then the following may be of help:
Ask for your test results!
BT Ignite carry out the following tests:
Line Length < 5.5km to pass
Line Length - This test is done so that BT can find out how far your
telephone master socket is from the exchange. It usually has to be within
5.5km for the 512K connection and if you want faster than 500kbit your line
length will need to be less than 3.5km from the telephone exchange.
Line Noise <= 55dB to pass
Noise - This shows how much noise is on your telephone line. For a pass, it
usually has to be less than 55dB for the 512K connection and less than 41dB
if you want faster than 512K.
Line Capacitance <180nf to pass
Capacitance - Capacitance acts as a filter, allowing certain frequencies to
pass and blocking others. In the case of telephone wires, which were not
designed for ADSL use, a high capacitance level can prevent the frequencies
used by ADSL from being transmitted properly. For a pass it need to be less
than 180nF, but ideally it should be less than 160nF.
"Whoosh" Test - The final test of line quality. <= 45db to pass
Whoosh Test - The BT engineer conducts this test to make sure that your line
has a signal loss of less than 45dB between the master socket and the
telephone exchange.
If the fail is marginal, ask to be re-tested!
Line gain
Dial 151 and ask them if line-gain has been enabled on your line. If it has,
ask them to turn it "off". This will degrade modem performance slightly, but
should help the ADSL line test results.
Too far from the exchange?
It might be worth calling "151" and asking if your line can be re-routed.
Please note that BT (or BTO) have no obligation to do this, so be persuasive
and charming rather than demanding! There may be a charge for this, and
re-routing your line does not guarantee a test pass so there is some element
of risk in this approach.
If you still can't get ADSL you will need to look at alternatives. Three
prime candidates are:
Leased line
ISDN
Satellite ADSL |