A PRANK THAT
The Music USB is a small USB flash drive looking device that, when plugged in, will play a tune.
The modified and updated version used in my real prank uses a CR2032 watch battery for power. It periodically would play a 5-second snippet of “Never Gonna Give You Up” every ~30min or so. Apparently, it was quite annoying.
|Start – Completion||January 2017-|
|Languages & Technologies Used||ATTINY85, Arduino/C, Piezo elements, USB, Watchdog Timer Interrupts|
I was thinking of some ways to maybe pull off a funny high-school senior prank. I decided that since the computers at my school had a free USB port on the side facing away from the monitor, this would be a perfect place to hide and/or power a pranking device. To me, the idea of the media center’s computers sputtering out video game theme songs whilst frantic librarians and students rushed to find the source seemed quite hilarious.
Development & Challenges
Unfortunately after completing my design I realized I could barely hear the music the piezo was playing! No one would even notice it if they weren’t in a completely quiet room.
A few months later, I was on adafruit.com when I read about “differential drive” for piezo elements. This method used two I/O pins to swat the voltage levels back and forth between high and low that allowed the Music USB to be twice as loud. Alas, the school semester was already too close to ending to have enough time to pull off the prank.  (so I waited until freshman year of college, pictured right is the improved device)