Here's how to make a "computer on a card" from the 1960s

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I want someone to do for a quantum computer, what this does for a digital computer. Is that so much to ask? Maybe I’d need VR goggles and liquid nitrogen to run the simulator, but as long as its something I already have in my basement, that would be cool with me.


Not falling for it. You’re jut trying to get me stuck in an infinite loop so you can swipe my lunch money.


Hm. I wonder if I could manage to work this into my lecture on cold war computing? Cause I bet that at least my HS class would get a kick out of this…


It’s pretty easy. First, let’s use the most common example, Shor’s algorithm. We’re going to factor the number 15 using a quantum computer. The classical precomputing analysis steps show us that it will require 7 qubits. So we start by printing out and taping up an array of seven cardboard boxes. Inside each box, we’ll place a radioactive element, a geiger counter, a vial of poison, and a cat …


I was given one of these for a class in Junior High. There was a curriculum that came with it, in a kit and we learned about computers along with our teacher. I recently bought one on eBay and what a time rush of memories holding it caused. I remember struggling to understand it, to complete exercises and my wonder at how it translates to an electronic computer.

There’s a great book called “the paper computer unfolded” by Mark Jones Lorenzo. There are groups for these on social media. 'Tis a wonder, this world of ours.

At that same time period, the MGM (Mentally Gifted Minors) program at the school bought an Altair 8800 kit. They assembled it but it did not work. The teacher found out that I messed with electronics and soldering, and he asked that I take a look at it. The problem was cold soldering joints and a few backwards capacitors and the like. I got it running and we entered ops codes through the panel switches.

This is probably why I still work as a computer engineer. (And maybe something to do with my marriage to my nerd wife that used to work at Bell Labs.)


Hopefully you’ll bring up the unusual Soviet ternary computers like the Setun.



Thanks, I’ll stick to the technology I grew up with…


There’s also SAGE-- which was the largest computer ever built-- it dwarfs the puny “computers” we use today.


That sounds very interesting.
As I’m on the wrong continent to attend - any chance of a link to further information?


Probably not, as it’s just the general lecture course.

My week on this includes talking about two people in computing history - right now, it’s Grace Hopper and RMS. I think expand and talk about a very general history of computing… probably not deep enough for most of the computer geeks here (I’m not a historian of computing, keep in mind). I do think it’s important to show kids who now have computers more powerful than those that got us to the moon where that comes from and how that connects to both the second world war and the cold war.


That was a sweet read. Welcome, comrade.


The Internet is the largest computer ever built.

We never had these in school, but this has triggered a memory of something similar, possibly given away with a comic in the UK… definitely in a novelty context. I remember sliding the tabs up and down and peering through the tiny cardboard windows, which soon started tearing. Well, I needed something to haunt me for the weekend.


A volvelle or wheel chart is a type of slide chart, a paper construction with rotating parts. It is considered an early example of a paper analog computer.

Volvelles have been produced to accommodate organization and calculation in many diverse subjects. Early examples of volvelles are found in the pages of astronomy books. They can be traced back to “certain Arabic treatises on humoral medicine” and to the Persian astronomer, Abu Rayhan Biruni (c. 1000), who made important contributions to the development of the volvelle.

A volvella for working out the position of the sun and moon in the zodiac, 15th century:

A volvella for working out Led Zepellin III, October 1970:

(Update: Boing Boing seems to have trouble displaying wiki images … the images were displaying, but when I did a bit of editing, first one then the other were reduced from images to links.)


Great story, thanks!

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I learned to use a slide rule in high school in 1962. My chemistry teacher was going on about how to use a slide rule to calculate numbers to three-place accuracy, using a giant, like eight-feet long, slide rule attached to the chalk board in the front of the room. The previous summer I had worked at minimum wage at a local tobacco shop, and had saved about 100 dollars. I took forty dollars and bought a Dietzgen magnesium slide rule at a local office supply store. I wore that thing in its leather-with-a-belt-loop case like a light sabre. I still have it, and it lives in my old briefcase, along with a very fine TI-30 calculator that similarly gets no use. Some time ago, I tore the slide rule apart, cleaned it with lighter fluid on a Q-tip, and re-lubricated it. When society collapses, I’ll be ready!


Cold war computing, you say?

Anata-ha supai koi no oberisku kieretsu desu?

Not all conversations about ternary ( or trinary ) operands need to lead to an intercept text via way of Dale { f } daphne series modifiers, Holly.

I will actually pursue the literature regarding the Russian technologies before plunging into ternary Raku, as they probably have some technological precedents I should be aware of before selecting the relevant design patterns.