This week I integrated the interrupter circuit with the newly repaired gate driver and ran initial audio modulation tests. The LCR meter finally arrived, allowing me to verify the primary coil inductance and tune the interrupter frequency to match the resonant circuit. I tested the audio input with simple waveforms (sine, square) and confirmed the plasma arc responds to the modulation, though the audio quality needs improvement – higher frequencies (>10kHz) modulate better than bass frequencies. I also adjusted the duty cycle potentiometer range for finer control. Next week I’ll optimize the audio input circuit with better filtering and work on improving low-frequency response for clearer musical reproduction.
Carnegie Mellon ECE Capstone, Spring 2026 – Caleb Doan, Jayson Ma, Jack Wang