This old Pifco All in One Radiometer belonged to my grandfather, it's spent the past 15 or so years in my fathers garage hidden behind a box of valves (a project for another day). I believe that these were sold from about 1930 to around 1950's for 12 Shillings and 6pence, somewhere in the region of £37GBP in todays money.
So here it is, still a bit crusty & dusty, but still happily working around 56+ years later. (I say this is a tear down but there is very little in this to show)
I was thrown here for a second that the common terminal had a red cap.
And, all those magical insides...
And still working, showing my Rigol is actually pumping out 5v.
The 60mA fuse had long since crumbled into dust, it's a very odd size but hopefully i can find something to replace it.