An astonishing old calculator - Numberphile
Why Hacker News recommends it
It is the go-to visual explanation of delay-line memory and early electronic calculators whenever the topic comes up.
What it is
Cliff Stoll shows and explains his two Friden EC-132 electronic calculators for Numberphile. The video covers how these early machines worked, including their unusual acoustic delay line memory.
Recommended by 1 HN commenters across 1 different months, 2017 to 2023.
What Hacker News said
Strong rec kdoherty · 2017-12 · on “Acoustic delay line memory (2014)”
There is also a fantastic video where Cliff Stoll describes the Friden EC-132 calculator and shows off its acoustic delay line here: [this video]
Cites major505 · 2020-10 · on “The Friden EC-130, one of the world's first electronic calculators”
Cool way to store the bits. I saw the other day a video about an old eletronic calculator that stores itens in memory usinglike a piano wire, and microfones, and small speakers, to make the cord vibrate, and store the value. It was the Friden ec-132 [this video]
Cites db48x · 2023-08 · on “111,111.1 meters is reliably 1 degree of latitude”
There were a lot of delay–line memories back in the day. It wasn’t just that they didn’t have memory chips; memory chips hadn’t been invented yet. [this video]