The Great Search: Miniature Ferrite Core Ring (Toroid) #TheGreatSearch #DigiKey @digikey @Adafruit

(Video) We were flipping through a cool old book on how computers were made and there was a section on ‘core memory’. This is how data was stored dynamically on computers before capacitive-based RAM. Instead of storing a charge on a transistor’s gate, the flip of a ferromagnetic core in a grid could store a single bit. Some folks make core memory for fun now – you just need some enameled wire and miniature ferrite cores! While the ultra-tiny rings of yore are no longer made, you can still get some pretty small toroids. Let’s see what’s available at Digi-Key!

Computers: Their History and how They Work by Richard B. Rusch (1969)

See on Digi-Key here!

See other episodes of The Desk of Ladyada in the playlist here and other Great Searches in the playlist here.


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1 Comment

  1. 80 mil to 14 mil diameter in 18 years gives a density doubling time of 2.4 years. (7.2 years for halving 1-dimension)

    Since 1972 that extrapolates to 21 density doublings (2M) or 7 linear doublings and cores should be 2^7 times smaller in diameter, or under 3 microns.

    Current hard drives use about 1 nm diameter domains, so a factor of 3000 in 1-dimension. The 1D doubling time since 1972 was 2.7 years instead of 7.2

    Things sped up.

    Unfortunately we only got the increase in 2 dimensions, so we don’t have hard disks with hundreds of thousands of platters, yet.

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