Just to add that if you don't want to purchase any new phones then the old method of walking up and downstairs still works. I'm not being flippant but new technology with new features rarely fully works with older equipment, it's designed that way for some obvious reasons.
Another solution might be to plug the hub phone socket into your old wiring - disconnecting your old phone wiring from the original master socket first - this is covered in great detail on here. That way your old phones will act as before over your old wiring.
Andy005, Well I could answer the phone in my study and if it's my mother-in-law call my wife upstairs but I really couldn't face two hours of the two of them chin-wagging whilst I'm trying to work in the room! I'm not being flippant, but BT has poorly thought out the default configuration by saying you can connect analogue phones but having a default setting that is incompatible with a purely analogue phone scenario and apparently no way to change it without a digital phone.
SRB, I will research that a bit more, but my phone wiring is off the back of a removable front to the OpenReach socket so I guess I'd need to either put an RJ11 jack on that wiring or use the wiring into the back of a new socket and find a male-to-male cable to plug between the SH2 and my new socket. Not having been a BT Engineer since the mid-60s (or ever) like half the people on the threads I've found so far I don't feel immediately confident about doing that!
I might still have somewhere the old DECT phones that came with Broadband Talk connecting to the original BT Home Hub 1 (or maybe 1.5). Would those connect to the Smart Hub 2 (temporarily) and be enough to change the Line Settings...or does it have to be one of the current BT Essential or Advanced handsets (I don't know anyone who has those I could borrow temporarily).
No, I'm afraid it would have to be one of the new phones. You can buy a "male to male" lead easily enough, so plugging that into the removeable faceplate and the other end into the hub, would give you the working extensions with the new DV line. Easier than removing the wiring and adding another socket, though not the neatest I will admit. Also requires the Hub to near the MasterSocket.
Thanks SRB, it sounds like that may work for now as the SH2, OpenReach Modem and OpenReach Master Socket are all fairly close in a cupboard under the stairs. The removed faceplate will be dangling on the skirting board as there's about 2 inches of wires before it goes through a wall (the OpenReach guy who fitted the modem put in a new Master Socket and connected it to pre-existing telephone extension wiring) and then "Polyfilla-ed" the hole. But I can close the door and nobody will know.
I may have a problem later when I can get FTTP as I doubt OpenReach will run the new fibre to the middle of the house to put the new fibre modem where the old ADSL one is and so the SH2 may need to go to a new place...although to be honest I can't even guess where they would plan an entrypoint but I guess they wouldn't try to pull fibre through the existing flexible conduit under a concrete drive and solid ground floor...but that's for another day.
I was able to acquire a BT digital handset to validate what was/wasn't possible with (1) an analogue phone connected to the back of the Smart Hub (2) an analogue phone connected to a Digital Voice adapter (3) a BT digital handset. The conclusion was that you need at least one BT digital handset and an analogue phone connected to a Digital Voice adapter (not the back of the Smart Hub) to be able to get functionality comparable to the previous pre-digital wired connection of two analogue phones to the master socket.
First up, the Line Settings confirmed that the line was set to Multi-Call by default on the Smart Hub. I changed it to Single Call.
I then made some tests by calling my landline number from my mobile whilst the line is in Single Call mode:
1) Answered call using analogue phone plugged directly into Smart Hub (henceforth called the "Hub Phone")
Hub phone: The call connects as normal. There is no method to initiate transfer of the call to another phone in the house.
Adapter: There is also no method for the analogue phone on the adapter to join the existing call.
Handset: The handset showed the option to Join a call, but it failed to connect to the only other phone it had in the list...the Adapter (which isn't on a call)
2) Answered call using analogue phone plugged into DV Adapter
Adapter: The call connects as normal. There is no method to initiate transfer of the call to another phone in the house
Hub phone: The phone has a dialtone, but calling a number failed. There is no method to initiate joining a call to another phone in the house
Handset: The handset can join the call on the Adapter for a 3-way call and then the Adapter phone can be hung up and the call continues on the Handset only
This achieves function similar to the two wired phones on a traditional landline call albeit with a few extra key presses
3) Answered call using Digital Handset
Handset: The call connects as normal. A transfer can be initiated, but the only option is the Adapter and not the Hub phone
Hub phone: The phone has a dialtone, but calling a number failed. There is no method to join a call connected to another phone in the house
Adapter: Successfully joins call transferred from the Handset as a 3-way call until the Handset hangs up and then the call continues on the Adapter only
Again, this achieves function similar to the two wired phones on a traditional landline call albeit with a few extra key presses
It seems that a phone plugged into the Smart Hub is not the same as a phone plugged into an Adapter ("remote" phones do not "see" it)
Whilst I did not re-test all options with the Line in Multi-Call mode, I don't think it is intrinsically the Line mode which affects call transfer handling
With the Line in Single-Call mode two analogue phones cannot join/transfer a call and only one phone can make/receive a call at a time
With the Line in Multi-Call mode I believe the only difference would be that both phones can act independently and have simultaneous calls
The only way to transfer/join calls is to have a BT digital phone to initiate call transfer or request to join an existing call on an analogue phone on the Adapter
So, you need a BT digital handset and a DV adapter for an analogue second phone (plugging it into the Smart Hub will not be enough even if it is close by) in order to have to phones transfer/join one call.
I believe BT had previously sent out BT digital handsets free of charge when upgrading to Digital Voice. For a single analogue phone plugging it in directly to the Smart Hub or using the current free option of a DV adapter is straight-forward, but for the many (possibly even majority) of users who have wired extensions in their homes the information I have seen is misleading as it suggests you can just use two analogue phones which is not untrue but hides the fact that these would behave as two entirely independent phones in the default Multi-Call mode (and if they had a way to change it to Single-Call mode they could only use one phone at a time not as they did previously with two phones on a single line with wired extensions).
There is an option suggested on the community pages about plugging in house wired extensions to the Smart Hub socket. This may not be for those who aren't tech-savvy, for example in my case there is 2-inches of extension wiring before it goes through a wall so if I unwire it from the Master Socket faceplate I'd need to join longer wiring to either a new socket and use a bought extension cable or splice the short wire to a longer wire with a jack to plug directly into the Smart Hub. This solution would also be incompatible, from a call transferring perspective, if the user subsequently acquired one or more BT digital phones as the "remote" phones would not see the wired analogue phones as per my testing above.
You can transfer calls between two handsets but you need two of the same BT DV handsets as the DECT implementation is, shall we say, "tweaked" to work with the smart hub 2. The adapter acts like another DECT extension phone, as far as the hub is concerned, however an old phone obviously won't have the DECT capability of a DECT phone, let alone BT's implementation of DECT. If you were to plug the hub phone socket into existing wiring, extension sockets would indeed behave exactly as they did before. If one extension phone is on a call and another extension lifted you will join the call. If multi call is off and you are on a call, on wired extensions connected to the hub, I would expect a DECT phone connected to the hub, to give an engaged tone if you tried to call out on it - however I don't have a Smart Hub 2, so can't confirm that, it's possible it does give a dial tone, but won't let you make a call because multi call is off. There are loads of options discussed across the forum, so pick one which suits your needs best and people will be happy to help with any questions you have.
I don't have a DV adapter, but have a DV handset and analogues phones connected via the hub socket. I can confirm that calls answered on DV are not available on the analogue phones and vice versa.
I suspect there is no connectivity between the DECT portion of the hub which the DV handsets and adapters use and the ATA via the green socket which analogue phones connect to.
Edit: post crossed with @SRB above