About 1965 Richard Smiley, a student at Carleton College in Minnesota, wrote a program that could play music (sort of) on an IBM 1620. You could listen to it on an AM radio placed near the machine. The 1620 was a variable word length machine, and the word length affected the time it would take to accomplish a task, thus changing the radio signal. Smiley exploited this variation to generate musical tones. IBM included this in the contributed program library that was available to all 1620 users.
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About 1965 Richard Smiley, a student at Carleton College in Minnesota, wrote a program that could play music (sort of) on an IBM 1620. You could listen to it on an AM radio placed near the machine. The 1620 was a variable word length machine, and the word length affected the time it would take to accomplish a task, thus changing the radio signal. Smiley exploited this variation to generate musical tones. IBM included this in the contributed program library that was available to all 1620 users.