According to J. Presper Eckert in “Who Needs Personal Computers?”, Sperry was planning to built a PC (and apparently built a prototype) as early as in the 1950s:
“During the late 1950s I was involved in trying to build what could now be called a personal computer, probably the first such machine to fit on a desktop. We used hundreds of magnetic core amplifiers and diodes, a few transistors and tubes, and a motor-driven drum for memory storage. The same motor powered a flyprinter, which typed the computer’s output onto a moving strip of paper. Unlike the first microcomputer systems, which came later, our machine included a keyboard for easy input. We figured we could sell our Desk Computer for $5,000. Some insurance firms expressed interest, but our executives just couldn’t see business need for that small a computer.”
I think something interesting happened when computers became mass-produced - before which, they were built as one of a short production run, before which each one was a unique design and implementation.
For my own definition of computer - something which performs computation - I’m quite keen on recognising the programmable calculators. Two notable early ones are Olivetti’s Programma 101
and the not-entirely-unrelated 9100 from Hewlett-Packard (“due to the similarities of the machines, Hewlett-Packard was ordered to pay about $900,000 in royalties to Olivetti”)
Both are great marvels of technology and engineering. Another machine which must be remembered is the amazing MCM/70, a portable/luggable machine, self-contained, with a one-line display and which swapped to cassette tape, and which offered APL as the programming language and user interface. https://www.xnumber.com/xnumber/MCM_70_microcomputer.htm
Oops, I meant also to mention the Memex, being an idea, from 1945, of a machine which allowed the user to bring up information and - crucially - to create links between items, and to annotate them, and to share these links. More than a personal computer, in some ways.
And people today, get mad when I refer to an Apple computer as a PC.
Yeah… I don’t care how mad they get. I still say that their machine is personally owned.