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A 1977 Time Capsule, Voyager 1 runs on 69 KB of memory and an 8-track tape recorder
(techfixated.com)
This is a most excellent place for technology news and articles.
The Commodore 64 came out in 1982 and famously had 64KB of memory.
Commodore VIC-20 came out in 1980 with 20KB as well.
20KB of ROM and 5KB of RAM, though that was expandable!