Hoperfully someone can help me solve this problem for my in-laws...

There are two telephone sockets (one downstairs and one upstairs) and two telephones, A and B - both corded phones.

Telephone A rings when plugged into both sockets, but telephone B only rings in the downstairs socket. Otherwise, telephone B is fine when plugged in upstairs - you can answer incoming calls if you hear the downstairs phone ringing, and can make calls as normal. It just doesn't ring when plugged in upstairs, although telephone A does.

There are no other devises on the phone circuit - just the two phones.

Any ideas why this is?

ta, WF

Do these have a higher REN? somebody will know !

It sounds like you have a designed for UK use only phone there (B), this means that to reduce costs they haven't included a ring capacitor in the phone.

This shouldn't make a difference with a correctly wired extension.

The master socket which by your description would be the one downstairs, has the ring capacitor circuit and thus called master socket.

The upstairs socket will be a slave socket or extension, this doesn't have the ring capacitor.

If the upstairs extension was correctly wired then the ring circuit would also be linked.

It sounds like the extension has only been connected with 2 of the wires, this being 2 & 5, this was probably because on the master socket they were the only two connected from the outside A&B line (this is correct).

However for the extensions you need pin 3 connected from the master socket to the slave, this is the wire used for the ring circuit.

Thanks BexTech. I'll pop the front off of the extension socket and see if there are only 2 wires.

WF.

No problem.

You'll need to check the master socket too, ensure there is the wire from the extension connected to 3.