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Teletype Model 33

The Teletype Model 33, an electromechanical teleprinter from the '60s with actual cylinders as its keys.
Published February 24, 2022

You think you know what a cylindrical keycap profile looks like, don't you? I'm talking about OEM, Cherry or MoErgo MCC.

Then you haven't seen this one, the real CYLINDER profile you may have been unaware of. The whole key of a Teletype Model 33 is a regular cylinder. What's more, modifiers are even bigger cylinders with larger diameter. :D

This is the type of chonker vintage stuff that I'll probably never own due to geographical reasons, despite the relatively huge number of pieces manufactured: in 1976, Teletype celebrated the specimen with the serial number 600.000.

Pic: Top view of the Teletype Model 33 ASR (click to enlarge)

Top view of the Teletype Model 33 ASR (click to enlarge)

According to this wiki page, Teletype Corporation's Model 33 terminal, introduced in 1963, was one of the most popular terminals in the data-communications industry until the late 1970s. It's a legendary electromechanical teleprinter designed for "light-duty office use", but it was usable as a computer terminal as well.

These machines not just predated video terminals like the Tektronix, appearing in 1969, but were also much cheaper ($600-1000 vs. $3,950).

Model 33s came in three versions with the Model 33 ASR aka ASR33 (depicted above) being the most premium – fitted with a punched tape reader, tape punch, and keyboard. The KSR version featured only the keyboard, while the RO model was the cheapest read-only alternative.


Since the Model 33 is such a lovely piece of history, it's no wonder that, similarly to e.g. ballpoint typewriters and plotters, it still has an active fan base.

Hugh Pyle runs @33asr, a Twitter channel dedicated to the ASR33, and he also maintains a GitHub repo with his Model 33 related hacks, projects and resources.

Pic: Teletype Model 33 art

Teletype Model 33 art

Thanks to his efforts, beside ASCII art and punch tape art, it seems you can play even Wordle on these relics. (For posterity after the span of millennia, Wordle was a word-guessing game and Internet phenomenon in early 2022.)

Finally, here is a close-up of a key, which happens to be Hugh's profile picture on GitHub:

Pic: Teletype Model 33 key

Teletype Model 33 key

Published on Thu 24th Feb 2022. Featured in KBD #67 (source).

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