So we didn't have to run back & forth from the control room, one of the "clever chaps" made up a box with two large key switches, which could be plugged into one of the GPOs conveniently mounted on pillars throughout the building.
I want to know how you got the whole of the General Post Office onto a pillar. I mean, that's going to be 10s of 1000s of people!
Or put differently - GPO is not a universal abbreviation and I haven't a clue what you're talking about. Abbreviations for bits of electrical kit do not, in general, travel well. e,g, UK abbreviations RCD, RCBO, ELCB.
But everybody else worked it out!
OK, for not you, who is indulging in some gentle "piss taking", but for anyone who is genuinely confused, it is a "General Purpose Outlet".
It is not as confusing as "plug tops", the very common term "jack plugs", or many others.
For instance, whenever I hear "AVR" I think of large motorised power transformers, & USB translates to "Upper Side Band!"
An interesting sidelight on "GPO" & Post offices:
In Oz, back in the day, the
organisation was the "Postmaster General's Dept " & a "GPO" was the main Post Office in each State capital, which was generally, a very imposing building.
"Australia Post" still use the term "GPO" for their headquarters in each State, but it is pretty much a "virtual" thing, the buildings themselves having been sold off to the ever salivating "Private Sector!"