March 1, 2021
Yet another PDP-1 riddle, extended mode.
Yesterday, we solved the mystery of two well-known images, formerly known as “The PDP-1 at the Tech Model Railroad Club”, with the help of the Hacker News community. A triumph of shared knowledge.
In 1971, the German artist Daniel Chodowiecki (1726 – 1801) commented his etching “Enlightenment”
(Aufklärung) by the words, “However, if the sun only rises, mists do no harm.”
(Indessen wenn die Sonne nur aufgeht, so schaden Nebel nichts.) In real life, mists rise only to reveal another bank of fog. Which is the very process of research. And this is certainly no exception. So this is a post about annother bank of fog, in the amazing form factor of a fully transitorized electronic contraption apt to manipulate 18-bit words in realtime according to a stored program and human interaction.
A story of trains, computers, and two images.
This is at the same time a continuation to what may become a loose series, namely, “Things on the Web that aren’t what they seem to be”, and the beginning of an entirely new one. Anyway, this is the story of two photos that are rather well known in the context of computer history. You may even have seen one or the other popping up on a website.
Since you are reading this blog, you may be even familiar with the broader context.
Context
In 1961, the MIT recieved a DEC
PDP-1 computer from Digital Equipment Corporation as a donation. It was one of the very first production models and DEC’s motivation was a multiple one: First, the PDP-1 was somewhat of a commercial version of MIT’s experimental TX-0 computer