Electrical Engineering
GDX2 Stereo Speakers
GDX2 is a 2-way speaker set I designed and built for my own personal and professional use. I designed the crossover filter for these relatively small speakers to have an F3 (frequency dropoff of 3 dB) of 80 Hz and a flat frequency response with deviation of plus or minus 1.5 dB for the entirety of the passband. This flat response allows for accurate reproduction of music for mixing applications, or for just general listening and enjoyment.
Features:
2-way system
F3 of 80 Hz
Ported for low frequency extension
Flat response curve. (Deviation of plus/minus 1.5 dB)
3/4" 11-ply birch exterior with 1/2" MDF interior
SEAS Prestige drivers
For more information, including design statements, and testing results, click the button below.
NES Arcade Joystick
A closeup of the final circuit
The prototype circuit for testing purposes.
The final circuit inside its temporary enclosure.
As a personal project, I wanted to have an arcade-style joystick for my vintage Nintendo Entertainment System. I did some research and reverse engineering to figure out how the NES gamepad works, and then began designing mine. Recreating the basic functionality was easy, as it requires wiring a 4021 shift register to the buttons and cable correctly. I also wanted to implement turbo buttons with adjustable speed. To do that, I built two identical 555 timer circuits with potentiometers to adjust the frequency between 1 and 20 Hz. Since the shift register uses pull-up resistors, and the timer outputs either 0 or 5 volts, I decided to have the outputs of the timers activate transistors, which would act as switches, grounding the necessary pins to register as button presses. The turbo buttons themselves provide power to the timer circuits. This project is a work-in-progress, but I have assembled the final circuit in a cardboard box as a temporary enclosure.
Bluetooth Earrings
My senior design project was sponsored by startup company, Teqnizan. They are developing Bluetooth-connected earrings, and it was my team’s responsibility to evaluate the performance of the prototype earrings and compare it to the performance of various other Bluetooth headsets currently on the market. We tested performance and comfort using a standardized protocol we developed that involved listening to the same thing in settings of various background noise, on all of the different products. In a lab setting, we then disassembled the products and tested the power usage.
Using our results, we determined which components should be used to improve the prototype. We wanted to maximize battery life, keep the earrings withing a certain weight limit, and make sure the volume was sufficient, all while staying within budget.
