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AV:Link ADSL Signal Filter - BT431A to RJ11 & BT431A

£299
The RRP is the manufacturer's recommended retail price of the item.
Limited Stock
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Description

The AV:Link ADSL signal filter is a white plastic adapter that converts a single BT431A telephone plug into two outputs: one RJ11 socket for ADSL broadband connection and one filtered BT431A socket for a telephone or fax machine. The internal filter separates the high-frequency ADSL signal from the voice-frequency telephone signal, preventing interference between the two devices when both share the same phone line.

Designed for UK residential and small office installations where ADSL broadband and a landline telephone connect to the same wall socket, the filter plugs directly into the BT431A master socket or extension and requires no tools or wiring. The ADSL modem or router connects to the RJ11 socket, while the telephone or fax connects to the filtered BT431A socket. Up to four filters can be used on a single telephone line if multiple extension points need filtering, though most installations only require one filter at the master socket.

The filter weighs 25g and measures approximately 60mm x 40mm x 25mm, so it sits flush against the wall socket without obstructing adjacent sockets or furniture. The white plastic casing matches standard UK telephone wall plates and the design includes no LEDs or moving parts, making it a passive, maintenance-free component once installed.

Specification
Weight 0.03KG
Colour White
Current rating 431
Type Modular (RJ)
Frequently Asked

Why is an ADSL filter needed?

ADSL broadband and telephone voice signals share the same copper line but use different frequency ranges. Without a filter, the ADSL signal can cause crackling, static or interference on the telephone line, and the telephone signal can disrupt the broadband connection. The filter separates the two signals so each device receives only the frequencies it needs.

Where should the filter be installed?

The filter plugs directly into the BT431A wall socket where the ADSL modem or router would normally connect. If you have multiple telephone extension sockets in the property and use phones on those extensions, each extension socket may need its own filter to prevent interference. Most users only need one filter at the master socket.

Can multiple filters be used on one line?

Yes. Up to four ADSL filters can be used on a single telephone line if you have multiple extension points. Each extension socket with a connected telephone or fax should have its own filter to prevent the telephone device from interfering with the ADSL signal.

Is this compatible with fibre broadband?

No. This filter is designed for ADSL (Asymmetric Digital Subscriber Line) broadband, which runs over traditional copper telephone lines. If your broadband is delivered via fibre-to-the-cabinet (FTTC) or fibre-to-the-premises (FTTP), you typically do not need an ADSL filter as the broadband signal does not share the voice line in the same way.

Shipping & Returns

Delivery UK delivery is £14.99, and delivery is free on all orders of £99 or more, in the UK and internationally.

Returns If you change your mind, you have 14 days from delivery to tell us, and a further 14 days to send the goods back. Return postage for a change-of-mind return is paid by you. Change-of-mind returns are subject to an inspection and handling deduction. See our full returns policy.

To arrange a return, call us on 020 8149 5199 or use our contact page.

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    Description

    The AV:Link ADSL signal filter is a white plastic adapter that converts a single BT431A telephone plug into two outputs: one RJ11 socket for ADSL broadband connection and one filtered BT431A socket for a telephone or fax machine. The internal filter separates the high-frequency ADSL signal from the voice-frequency telephone signal, preventing interference between the two devices when both share the same phone line.

    Designed for UK residential and small office installations where ADSL broadband and a landline telephone connect to the same wall socket, the filter plugs directly into the BT431A master socket or extension and requires no tools or wiring. The ADSL modem or router connects to the RJ11 socket, while the telephone or fax connects to the filtered BT431A socket. Up to four filters can be used on a single telephone line if multiple extension points need filtering, though most installations only require one filter at the master socket.

    The filter weighs 25g and measures approximately 60mm x 40mm x 25mm, so it sits flush against the wall socket without obstructing adjacent sockets or furniture. The white plastic casing matches standard UK telephone wall plates and the design includes no LEDs or moving parts, making it a passive, maintenance-free component once installed.

    Specification
    Weight 0.03KG
    Colour White
    Current rating 431
    Type Modular (RJ)
    Frequently Asked

    Why is an ADSL filter needed?

    ADSL broadband and telephone voice signals share the same copper line but use different frequency ranges. Without a filter, the ADSL signal can cause crackling, static or interference on the telephone line, and the telephone signal can disrupt the broadband connection. The filter separates the two signals so each device receives only the frequencies it needs.

    Where should the filter be installed?

    The filter plugs directly into the BT431A wall socket where the ADSL modem or router would normally connect. If you have multiple telephone extension sockets in the property and use phones on those extensions, each extension socket may need its own filter to prevent interference. Most users only need one filter at the master socket.

    Can multiple filters be used on one line?

    Yes. Up to four ADSL filters can be used on a single telephone line if you have multiple extension points. Each extension socket with a connected telephone or fax should have its own filter to prevent the telephone device from interfering with the ADSL signal.

    Is this compatible with fibre broadband?

    No. This filter is designed for ADSL (Asymmetric Digital Subscriber Line) broadband, which runs over traditional copper telephone lines. If your broadband is delivered via fibre-to-the-cabinet (FTTC) or fibre-to-the-premises (FTTP), you typically do not need an ADSL filter as the broadband signal does not share the voice line in the same way.

    Shipping & Returns

    Delivery UK delivery is £14.99, and delivery is free on all orders of £99 or more, in the UK and internationally.

    Returns If you change your mind, you have 14 days from delivery to tell us, and a further 14 days to send the goods back. Return postage for a change-of-mind return is paid by you. Change-of-mind returns are subject to an inspection and handling deduction. See our full returns policy.

    To arrange a return, call us on 020 8149 5199 or use our contact page.