Just been at www.practicallyclassics.co.uk (a forum I use far too much 
...) where some kind soul just posted this video clip:
https://www.youtube.com/watch?v=HeEWtNaW6KE
UK members might care to comment on the use of a BT 431A/631A plug on the old telephone shewn in the clip. Sure & that should have been fitted with a Plan4 plug, like this one:
...) where some kind soul just posted this video clip:https://www.youtube.com/watch?v=HeEWtNaW6KE
UK members might care to comment on the use of a BT 431A/631A plug on the old telephone shewn in the clip. Sure & that should have been fitted with a Plan4 plug, like this one: