Installing ADSL Microfilters

Published 12/05/2004 10:37   |    Updated 09/06/2009 15:51

How do I install the supplied ADSL microfilters correctly?

Your BT Broadband Installation Kit includes two types of microfilter:

  • A Double socket microfilter for use where you will be installing your broadband router. This allows you to connect your router, and also a telephone if required, to one phone socket.

  • A Single socket microfilter for use at any other phone socket where you have a phone, cordless phone base station, answering machine, fax machine, digital TV boxes (e.g. Sky+) etc. connected.
  You should install these microfilters as follows:

Single Socket
 - At any other phone sockets on same telephone line:

  1. Unplug the phone cable from the telephone wall socket.
  2. Connect the LINE end of the microfilter to the wall socket.
  3. Connect the phone cable to the socket marked PHONE on the microfilter (A).

 single socket filter setup


Dual Socket - At the phone socket where you install the router:

double socket filter setup

  1. Connect the LINE end of the microfilter to your telephone socket.

  2. Plug one end of the grey ADSL Line Cord that came with your router into the DSL/HPN socket on the microfilter (B) and the other end into the DSL socket on the back of the router (C).

  3. If you want to connect a phone where the router is located, plug it into the socket marked PHONE on the microfilter.


Click here for typical filtering scenarios for a Broadband connection.


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