Digtal Voice etc

[#1]

Asking for a friend as I'm on plusnet and will move to FTTP and give up the landline later this year.

I'm told that almost all phones other than museum pieces, will be capable of making and receiving of calls, if plugged into the green socket on a BT Hub 2. You can't use that green socket to connect to existing internal extension wiring. It's one phone for the green socket but you could have a long lead from your one phone to the router. BT will sell a plug in digital voice adapter for any extensions. Overall you are limited to 5 handsets per connection. Is that correct?

If so does anyone know the technical reason why extensions won't work? Is it because the extensions are not powered?

[#2]

Using the BT Hub 2 is only true for BT customers.  There are plenty of other options though.  I've just detailed some here.  What you can/can't plug into the BT Hub 2, or an ATA (see linked thread), is dependent on the combined REN of the devices you are plugging in, and what REN the Hub/ATA can support.  It's the same with the existing PSTN as well.  The Hub/ATA/PSTN supplies a certain amount of current to the devices connected to it.  Each device needs a certain amount of current to work.  The combination of all the devices connected can't exceed the current supplied by the Hub/ATA/PSTN.

I believe it is possible to connect a Hub/ATA to your existing extensions in your house, but a little bit of work would need to be done to disconnect it from the master socket first, by someone who knows what they are doing.

[#3]

I believe it is possible to connect a Hub/ATA to your existing extensions in your house, but a little bit of work would need to be done to disconnect it from the master socket first, by someone who knows what they are doing.

to expand a little on @pjmarsh says above. It's referred to as 'voice reinjection' and there's a useful article here

https://support.aa.net.uk/VoIP_How_to:_Voice_reinjection

[#4]

Thanks - apprecited

[#5]

You could try something like this to connect your sockets.

BT to BT plug.