OKI, N.; http://lattes.cnpq.br/1525717947689076; OKI, Nobuo.
Resumo:
This work develops a harmonic distortion meter for measurement in the audio-frequency range (20 Hz - 20 kHz). This instrument includes a low-distortion sine wave oscillator and a reject-band filter that works in tune with the oscillator frequency. Also, a comparative study of sensitivities regarding the frequency and selectivity of several active filter configurations for rejection of the fundamental component of the test signal was performed. Low-pass and high-pass active filters are developed and implemented to eliminate high frequency noise and 60 Hz network interference.