IBM Selectric Typewriter & its digital to analogue converter

110816 Like and subscribe. This is an archive, check the link in the end if you are. Using slow motion video Bill Hammack, the engineer guy, shows how
IBM's revolutionary "golf ball" typewriter works. He describes the
marvelous completely mechanical digital-to-analogue converter that
translates the discrete impulse of the keys to the rotation of the
type element. (This is the typewriter featured on the television series Mad Men.)
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