They have a lot of slide rules in the museum of computers in Mountain View, I spent a a long visit there looking at stuff, and felt bad for some family members that came along and were bored. Regarding calculators, a while ago I got a HP35s (A somewhat recent one but purposefully made with a retro look) calculator and use it at work, infrequently but with great joy. It has a fair amount of memory and can be programmed with a lot of digging in the manuals.
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I love how the equal sign and plus are the same key. Lol.
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We really shot ourselves in the foot by going metric.
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The profile picture is quite a give away 
I’m old enough to have longed in my early youth for a slide rule so much that I built several using cardboard and log tables.
Considering I was about 10, the results were quite decent.
I got my first when my mechanical engineer grandpa died ( 
), but by that time I already had a battery devouring TI-30 and also a Sinclair kit contraption (I love RPN, and still do use my DM42 every day…).
Pfft. For about 10-12$ you can get 150F. 
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You can get a perfectly good slide rule for $20 or so from ebay. The expensive ones tend to have a bunch of extra scales that generally do things that are typically rare use cases and much easier to do on a computer. The basic C, D, A, B, and CI scales will do multiplication, division, squares, and square roots. K scale allows you to calculate cubes and cube roots.
They’re neat devices, pleasant to use, and the more complex ones are works of functional art. And there are some cases I find where their limitation to 2-3 significant digits helps me avoid getting buried in unachievable precision. But barring a global collapse there’s really no reason to use one other than you just want to.
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I bought one of these at a community yard sale in the 90’s for a few dollars haha
I sense a novelty song in the making.
Slide rules aren’t that useful for coming up with answers, but they were very useful for teaching some concepts that really need to be learned but aren’t.
- Proportion and inverse proportion.
- Significant digits.
- Estimating results to the nearest decimal.
Those are very important skills and understandings.
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“Someone Stole My Slide Rule” was the one hit single from my all-nerd Garth Brooks tribute band.
We used scientific calculators in our high school science classes (circa late 70s, early 80s) But a few of our teachers showed us how slide rules worked.
One classroom had a giant (six foot, maybe?) slide rule to demonstrate the concepts.
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I have a few of these circular conversion tools from the Army. Nuclear weapon yields, antenna power, jamming strength for freqs, artillery wheel, etc. I guess all that shit’s done by various boxes these days. I would love to see the crypto gear for FM transmitters, if that’s still a thing.
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I got a wooden slide rule the same way in the late 70s just out of curiosity. By that time I already had my TI-30.
Used to have fun fucking with the division/corps brains during our giant board game training exercises. Our unit would play the Sovs and during my night shift, when things were generally slow, we’d break out circles of various radii and flop them on the map just to stir the pot.
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Man, these take me back … high school in the mid-seventies, we all used one of these. On the back was a periodic table of the elements (I think we had like 70-80 of 'em back then ;-). There was an insert inside with innumerable conversion factors and important-ish numerical constants.
On the topic, I’m also somewhat nostalgic for the eyesight needed for seeing that print!
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My university calculus instructor had written a textbook on calculator math, but required slide rules in class. He spent his spare time investing, and retired young. Maybe he had a good idea there?
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Not as scary as my actual picture! Anyway, the main thing I retained from learning about sliderules was to spot ridiculous numbers. All that knowledge about log-log tables is long gone.
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“Area predictor?” As in using a circular slide rule to predict area? I’m sure there’s more to it than this but I’m picturing a pie chart like this one:
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It’s for estimating the iniatial fallout area after a nuclear detonation, determining expected fallout arrival time, and determining who needs to evacuate and who should shelter in place. It is used as a map overlay
The inputs to the plotter come a series of other nomograms that take into account the windspeeds and directions at vatious altitudes. The data is distributed down in the form of an NBC-3 report.
For personnel who shelter in place you can use that “whizz wheel” shown in the picture to determine the best time to evacuate.
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