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Connecting Hub 3 to Extensions

I was looking around for pin out information with little success so I though posting some photos may help others.

As I did not want several connectors and coils of cable to connect my phone line to the Tel1 port on the HUB I purchased a standard RJ11 Lead (only needed 1/2 of it so did not matter what type.

You may need to substitute your colours with the cable positions of mine as many people will have different colour cables.

Existing Master (Ignore 2nd Line on Left)Existing Master (Ignore 2nd Line on Left)

The end of the 1/2 of the RJ11 Lead I am UsingThe end of the 1/2 of the RJ11 Lead I am Using

Pin 1 Black
Pin 2 Red
Pin 3 Green
Pin 4 Yellow

Only Pin 2 and 3 are required.

BT Front Face Plate RemovedBT Front Face Plate Removed

2 - Blue
5 - White / Blue

Notice numbers are 5 3 2

Fed cables through into the backFed cables through into the back

Connected :
Extension 2 - Blue - Red - RJ11 2
Extension 5 - White/Blue - Green RJ11 3

Regardless of cable colours as mine may well be different to yours :
Extension 2 - RJ11 2
Extension 5 - RJ11 3

Front replaced with connections insideFront replaced with connections inside

All Plugged in and workingAll Plugged in and working

So now I have my main phone working on its extension with a RJ11 'flying lead' from the back of the master socket to the Hub 3.
Plugging a phone into the master socket I get a dial tone for a temporary random phone number that BT has assigned (found with 17070), plugging into my extension (from the Hub 3) I get my number that was transferred to virgin media.


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Wise owl
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Re: Connecting Hub 3 to Extensions

The above is a useful reference for anyone with the tech skills for a bit of DIY telephony.

By way of a minor correction for clarity, the RJ11 is 6P4C = 6 Position 4 Conductor. The first and last pins (1 and 6) are unused so the centre two pins in use are actually pins 3 and 4

This link seems to be the most consistent info I have found on the subject of pin numbers

Your info as shown makes sense but may cause some confusion if your RJ11 pin numbers are compared with other reference sources.

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Re: Connecting Hub 3 to Extensions

Forgot about that, got carried away with the 4 cores rather than including the 1 and 6 position blanks.  Rather than try to post and edit I will leave as is now because I think its clear enough.  Probably find most people will count the RJ11 at 1 to 4, as the 'real' 1 and 6 are hard to notice.

Guess this would be more accurate


Pin 1 Blank
Pin 2 - Core 1 Black
Pin 3 - Core 2 Red
Pin 4 - Core 3 Green
Pin 5 - Core 4 Yellow
Pin 6 - Blank

Only Cores 2 and 3 are required. (Pins 3 and 4) (Centre Pair)