This technique goes back to the early days of computers. Here's a video of the IBM 1401 punch card computer (1959) at the Computer History Museum playing music

This technique goes back to the early days of computers. Here's a video of the IBM 1401 punch card computer (1959) at the Computer History Museum playing music on an AM radio: https://www.youtube.com/watch?v=EPk8MVEmiTI https://www.youtube.com/watch?v=EPk8MVEmiTI The same computer could also play music using the line printer: https://www.youtube.com/watch?v=Lu4SxJqU9I4 https://www.youtube.com/watch?v=Lu4SxJqU9I4 I discuss how the line printer music worked here: http://www.righto.com/2019/09/risky-line-printer-music-on-vintage-ibm.html http://www.righto.com/2019/09/risky-line-printer-music-on-vi...