Household noise primarily originates from AC lines, fluorescent lights, and appliances, with significant frequency components at 60Hz and its harmonics, including 120Hz, 180Hz, and higher multiples. Modern electronics often incorporate input filters to minimize harmonic distortion, which helps reduce the overall noise impact on electrical distribution systems. The third harmonic in three-phase systems returns via neutral conductors, necessitating conductor sizing to match line conductors in buildings. Additionally, switching frequencies from power supplies can introduce noise in the tens to hundreds of kilohertz range, which is often not synchronized with the line frequency. Observations indicate that electronic devices, like TVs and computers, can interfere with each other, highlighting the pervasive nature of household electrical noise.
