Punched tape is a form of data storage developed in the Nineteenth Century from weavers' loom cards and used in various forms through the 1980s. The location of holes in a roll of paper indicate code. YouTube user 256byteram made this synthesizer that uses a punched tape reader as his/her entry in a contest for creative uses of the 555 timer integrated circuit:
It is a three channel music synthesiser, capable of four octaves per chanel. The 555's are used to generate each octave for each voice (or channel). There are twelve 555 timer IC's used for the synthesiser section and two more for tempo control and paper speed. It is sequenced by a Heathkit H-10 paper tape unit and programmed with a 486 PC running QBasic (seriously, it's easier).
The musical piece is Bach's Invention #8.
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