Audio Jack Reader - Signal Processing
Arduino-based signal processing experiment for phone-to-microcontroller communication via aux cable. Explores audio signal transmission, analog-to-digital conversion, and creative data transfer methods using standard audio interfaces.

Overview
The project was originally designed to allow iOS device to communicate with an Arduino through Audio Jack and therefore transmit radio signals to my first Spidy project. I customized my own display library so that all my projects with display has the cute spider startup logo.
Schematics
I’ve learned to sketch detailed schematics for the clarity of mind after my first radio controller project’s circuit ended up in mess and fried.
Soldering
I acquired some tools to help with circuit design and soldering. I soldered two Arduinos to test out the Arduino-to-Arduino communication systems through I2C. (also called Primary-Secondary, Leader-Follower, or Parent-Helper)
CAD Design
I designed and printed the project encase on Tinkercad. The battery slot seems to be a perfect fit.
Channel Testing
I played Uptown Funk to test if the channels work independently from each other. It seems to work as expected.
Sinusoidal Waves Testing
The Arduino is able to perceive precise raw data without much noise from my iPhone through audio jack and my partner’s app. I started working on building my own communication protocol. I attended Yale summer course Age of Digital Information for that purpose.
Links
Code: https://github.com/jiatinglu99/Arduino-Audio-Translate
3D: https://www.tinkercad.com/things/itZXyCotgia