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IBM Selectric Typewriter & its digital to analogue converter

IBM Selectric Typewriter & its digital to analogue converter on HackerTube: recommended by 4 Hacker News commenters across 5 separate months, 2016–2025.

engineerguy

explainer · evergreen

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Bill Hammack of engineerguy uses slow motion video to show how the IBM Selectric typewriter works. He focuses on its fully mechanical digital-to-analog converter, which turns key presses into rotation of the type ball.

Why Hacker News recommends it

HN commenters recommend it whenever the Selectric comes up, as a short, excellent explanation of its internals.

people recommended it
4
separate months
5
strong recommendations
1
discussed on HN
2016–2025
“I highly recommend watching”
— voxadam, Apr 2023, in “DIY IBM Selectric type balls give ’60s typewriters new life (and Comic Sans)”

What HN commenters said

8 Hacker News comments link this video. Each one links back to its thread.

voxadamApr 2023Strongly recommends

The Selectric is a fascinating machine. I highly recommend watching "IBM Selectric Typewriter & its digital to analogue converter"[0] by The Engineer Guy. [0] ▶ this video

in “DIY IBM Selectric type balls give ’60s typewriters new life (and Comic Sans)” · View on HN

voxadamSep 2025Recommends

Bill Hammack (engineerguy) has an excellent video on the IBM Selectric titled IBM Selectric Typewriter & its digital to analogue converter .[1] [1] ▶ this video

in “Comic Sans typeball designed to work with the IBM Selectric typewriters” · View on HN

golem14Jun 2023Recommends

To deepen the wonder, I'd be interested to see the longevity per material (PLA/Nylon/metal/...). I'd expect a lot of trial and error to deal with shrinkage and the probably high precision needed by the Selectric. But this is a great repository, thanks a lot! P.S. excellent short video by Bill Hammack on the Selectric internals: ▶ this video

in “How to make your own Selectric Typeballs” · View on HN

djmipsMar 2023Recommends

You might enjoy these. IBM Selectric Typewriter & its digital to analogue converter ▶ this video The Whiffletree: A mechanical digital-to-analog converter [link]

in “Mechanical aircraft weight and balance computer using whippletrees” · View on HN

dghughesJun 2016Recommends

You may enjoy Bill Hammack's video "IBM Selectric Typewriter & its digital to analogue converter" ▶ this video

in “Xerox Alto Restoration Part 2: Firing up the monitor [video]” · View on HN

chiphMay 2020Cites it

One of the interesting things about the Selectric is that it contains a mechanical digital-to-analog converter .. a Whiffletree mechanism. ▶ this video

in “A 1973 IBM Selectric typeball recorded dancers' body movements” · View on HN

Show 2 more comments
pasMay 2018Cites it

A distributed system will never be as intuitive as MS Word, which is basically the digitized version of stone tables, or papyrus, or whatever thousands of years old thing we are already familiar with. Or just remain a bit more strict and look at typewriters. Word is a typewriter. People look at typewriters and sort of understand them after pushing one-two buttons. Yes, there are hidden gems and details and a long road from mechanical typewriters to Word and laser printers (e.g. ▶ this video ), but people are a lot more intuitive about these pieces of hardware and software, because they are simply updates on existing tech. Distributed systems is a new, and hitherto an explicitly unknown concept for many people. And with minikube you can set up k8s as easily as MS Office. (Or you can use Typhoon [link] .. ) And it's trivial to package up all this into a website, like Office 365 and GKE [link] . Or you can run it on your own PC with minikube and Virtualbox/KVM/qemu, and similarly you can install Office locally. But it does not make sense for one and it increasingly makes less for the other too.

in “Will Kubernetes Collapse Under the Weight of Its Complexity?” · View on HN

hwillisJan 2018Cites it

As in, were they fast enough to be used with other layouts? Yeah, but this was back when letters were dictated- secretaries didn't go switching to dvorak. Any typewriter could technically use any layout, since you'd just have to swap out the characters. The biggest advantage of the selectric was that you could swap out the ball to get different characters or fonts. The ability to get italics was a pretty big deal. Here's Bill Hammond talking about them: ▶ this video

in “Operation Gunman – how the Soviets bugged IBM typewriters (2015)” · View on HN

Topics & tags

Mechanical & precision engineeringHistory of computingibm selectrictypewritermechanical computingwhiffletreedigital-to-analog