Making a Ukulele Tuner with Javascript

)I just got a ukulele and I love it. I play it nonstop. Because of the temperature changes in my room and how often I play it, the instrument goes out of tune quite often. I wanted to write a simple tuning program that could play a solid sine wave at the frequencies I needed it to. I found it very easy to tune off of a loud sine wave instead of the sound of a ukulele string being plucked over and over again like most ukulele tuners. This one is going to be very short because this program is very simple and to the point.

DJ Hard Drive Turn Table Part 3 - Playing Audio

So now the turn table is writing output to the serial connection off of the Arduino. This is very good. But what good is it if we can't play audio with it? That's what this part is all about: translating the signals from the turntable into audio modulations that we can hear. In this case, we're speeding up and slowing down a audio track. Let's get started!

DJ Hard Drive Turn Table Part 2

Welcome back to this episode of "Why isn't this working?" This week, we have the DJ Hard Drive Turn Table. When we left off, we weren't getting accurate directional readings from the drive. Needless to say, that kinda sucked. So I took it to an oscilloscope to figure out what was going on with the output of the op amps. It turns out it was a really weird problem.

DJ Hard Drive Turn Table Part 1

There are tons of tutorials on how to do this on the internet. The hard drive is an amazing part to do this with because the motor and bearings are so smooth and provide very low resistance of rotation while still being light. It could also turn itself (having a motor and all) and, best of all, it was free because my roommate dropped it and it stopped working. Which is a shame because it was 2.5TB. Regardless, I knew what I wanted to do with it almost immediately.