Installing your ADSL filter
Filtering your phones is imperative because an ADSL filter takes any trace of the ADSL signal out of the phone line. Obviously because no ADSL signal comes through a filtered line, it must be used on the phones and CANNOT be used on the modem if your service is to work.
Filtering of the ADSL signal off of voice jacks in your home or business is critical to the proper functioning of ADSL service.
This is to protect the ADSL connection from the voice. Improper filtering typically results in no ADSL service
Every single device plugged into the phone line except the ADSL modem itself must be filtered.
Note: it is not okay simply to not use a phone device--if it's plugged in to the phone line; it must be filtered even if it's on-hook.
If your ADSL service is not working and you do not have line sync, the best thing you can do as part of troubleshooting is to unplug every phone device in the house and see if you get line sync.
There are two main ways to filter the voice side of your service. In-line microfilters (this is what comes with your Billion modem) are small filters that filter each device plugged into the phone line.
You must have one for every device that plugs into your phone line and this includes faxes and anything else.
The picture above shows a filter on the phone attached to a Y adapter that you can purchase from just about any electronics shop. Notice the phone has a filter and the ADSL modem does not. If you wish to still use your dialup modem while you are using ADSL that must be filtered as well.
Alternatively, you can use an ADSL 'splitter' (central filter) which filters all voice jacks in your house while a separate dedicated line goes to the ADSL modem.