Talks to Watch

IBM Selectric Typewriter & its digital to analogue converter

1.1M views · Nov 7, 2010 · 3:05 · 4 HN recommenders · 8 mentions · discussed 2016–2025

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

“I highly recommend watching”HN comment, 2023

What Hacker News said 8

Strongly recommendsvoxadamApr 2023

“I highly recommend watching”

Fascinating look at how the Selectric works

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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
RecommendsdghughesJun 2016

“You may enjoy Bill Hammack's video”

Bill Hammack's explanation of the IBM Selectric

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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
RecommendsdjmipsMar 2023

“You might enjoy these.”

Mechanical digital-to-analog conversion in the Selectric

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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
Recommendsgolem14Jun 2023

“excellent short video by Bill Hammack on the Selectric internals”

Short look at Selectric internals

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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
RecommendsvoxadamSep 2025

“Bill Hammack (engineerguy) has an excellent video on the IBM Selectric”

Excellent explanation of the IBM Selectric

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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
Cites ithwillisJan 2018

Explains Selectric swappable typeballs

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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
Cites itpasMay 2018

Example of hidden complexity behind familiar hardware

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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
Cites itchiphMay 2020

“One of the interesting things about the Selectric is that it contains a mechanical digital-to-analog converter”

Selectric contains a mechanical digital-to-analog converter

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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