I used an Arduino to generate sin waves of the appropriate frequency which are then triggered by the keypad.This project uses an external speaker to play the tones. The arduino sends audio data via AUX cable.Features-Plays the basic notes SA, RE, GA, MA, PA, DHA, NI, SA, as well as the komal and teevra notes re, ga, teevra ma, dha and a note of the next octave for total 13 distinct notes.A test button which plays all these notes in succession when pressed.A record feature: Press this button to begin recording. The led attached to pin 13 will blink while it records.Play feature: Play the recorded sound.”

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