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Modified Nasa Chordcharts and Lessons
Why “Modified Nasa”? Is it in fact modified Alpha-dot1)? No, but they seem to have happened around the same time. I don't in fact know the origin of this chording system. InfoGrip used it for years on their now discontinued BAT chording keyboard, but early on I was told that NASA developed it. If you know more or can provide a footnote, please let me know.
Greg