1 HN user recommended this explainer1 month2017–2023score 1.5
Years with an HN recommendation, 2007–2026
It is the go-to visual explanation of delay-line memory and early electronic calculators whenever the topic comes up.
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.
“There is also a fantastic video where Cliff Stoll describes the Friden EC-132 calculator and shows off its acoustic delay line here” (HN, 2017)
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]
Shows Friden EC-132 storing bits in vibrating wire.
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]
Illustrates delay-line memory from before memory chips.
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