BT Brodband and phone Problem .

18 Nov 2007
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West Glamorgan
United Kingdom
Hi folks.
I have had BT Broadband added to an existing BT phone line. The line comes into a BT master box, which has three extension lines coming off it, all of which worked fine for phones. When we plug the ASDL filter into the master box,with the modem connected, the modem cannot connect to the broadband. Do we have to have a filter in each extension socket, regardless of whether or not it has a phone connected?
If not.....If we take the small front cover off and connect in where the small cover connects, fine. If we disconnect the extension cables from the small cover and replace the cover, plug in the filter , fine. I have checked the wiring connections to each of the three extensions, ( each wired individually from the master box ) with the wiring diagram in the sticky at the beginning of this forum and they are fine. As soon as we connect any one of the extensions, the broadband stops.
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You require a filter on every phone. The only device which doesn't require a filter is the modem itself. The extensions themselves shouldn't require filtering if unused, however, unsuitable cable or a wiring fault would cause issues.

The easiest thing to do would be to replace the faceplate with a filtering type, such as this:

Then you simply connect your extensions to the filtered terminals.
If you are going to leave the ADSL router/modem at the NTE master socket, then the master NTE filter is the way to go and will sort your problems.

As a short term test, try disconnecting just the terminal 3 in the master socket front plate - you may find this allows the router/modem to sync.
As well as needing a filter for every phone as such, remember that any other equipment connected to the line except for your DSL modem also needs to be connected via a filter. That includes answering machines, fax machines, dial-up modems, auto-dialers on alarm systems, satellite receivers with a telephone connection, etc., so make sure you don't have anything like that on one of the unfiltered extensions.

I'll echo the advice about installing a single filter at the NTE if possible. It will always give superior results compared to multiple filters at all the extensions.
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Thanks for the replies.
I have ordered one of the XTE-2005 Master Faceplates and will let you know if it fixes the problem.

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