Cars continue to copy the smartphone business model, now have mandatory pre-installed services and apps (and the tracking that comes with them):

The biggest challenge with filing expense reports is deciding which ⁨⁩ adding machine in my collection to use to add up receipts. Today's winner is an RC Allen model 75. ⁨

Here's a bonus video of what happens when you divide by zero on an electro-mechanical calculator.

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My Marchant Silent Speed is all cleaned up and ready to go with the rest of my collection!

Here's another view of the same operation from the back so you can see more of the gears move.

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It's worth mentioning that this is doing long division via repeated subtraction completely mechanically, just using the electric motor to power the gears. If you watch closely you can see it detect underflows, increment, and then shift right to the next digit.

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Success! A little cleaning and lubrication freed up the stuck registers enough to do long division. Here's the Marchant Silent Speed approximating Pi.

The Marchant Silent Speed ⁨⁩ ⁨⁩ restoration begins! Here's hoping this is as far as I have to take it apart today.

Tune in to our new episode! @katherined and @dsearls talk to @kyle of @purism about the data cars collect, where it goes, and how we’re really just driving around in a smart phone that we don’t even own.
Visit the following link for full episode -

#Cars #Technology #Privacy #Podcast #newEpisode

From John Wolff's museum:
"The Marchant "Silent Speed" and its descendants use a complex and unusual continuous-drive mechanism based on proportional and differential gearing. Every column incorporates a ten-speed gearbox with three drive shafts and five selectors. The accumulator tens-carry mechanism is contained within the carriage, using a differential gearing mechanism with two planetary gearsets per digit."

See also Jaap's pages:


Anyone interested in mechanical engineering should definitely check out the *analog* carry mechanism in these Marchant calculators that relies on planetary gears. These Marchants are arguably the high water mark for electromechanical calculator engineering.

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Check out the latest addition to my ⁨⁩ ⁨⁩ collection! This is a Marchant "Silent Speed" 8D from 1940, a fast electromechanical analog calculator that can even infinite loop if you divide by zero. I'll be refurbishing it this weekend to make it fully functional.

I'm glad that articles like this by Tatum Hunter that walk you through how to opt out of cellular carrier tracking exist, but I'm sad they are necessary. This is exactly why we created the AweSIM service.

I did many convergence demos with my at . It's so fun to watch the moment when people *get* convergence after seeing me drag a known Linux desktop app between screens and have it morph based on screen size.

If you wanted to know why I'm thankful I don't need to replace my car, and if I did, it wouldn't be with a modern one, here's why:

loud sharp noise, small-but-loud explosion in a small room (no injuries 

This has the side-effect of reminding me how to use each of these calculators, as they all have different methods to perform basic arithmetic, none of which are intuitive.

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typically degrade through lack of use. Oil/grease gets stiff, dust/dirt takes over. My solution is repeat the simple calculations I usually perform in my head or on my computer on one (or more) of my calculators to exercise them.

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