On Tuesday, 8 October 2019 22:40:55 UTC+1, T i m wrote:
Did I describe it correctly above? 'Dolls eye exchange', Jacks on
weighted cords with toggle switches and a operator position with
rotary dial and headset?

That would be a PMBX - manual exchange. Unless it was a PABX with a cord board like a PABX2

https://www.britishtelephones.com/pabx2.htm

I picked up a Plantronics Blackwire 5220 USB one £10 in the Cancer
Research shop recently.
Sounds like a result.
I think they still have one left.
Were they new OOI?

I assume not, as not in boxes etc. Works fine for talk and listen, just haveb't got the driver to talk to Dragon yet. Which may be Dragon's fault of course as it is about 10 years old.

Owain