Total Harmonic Distortion (THD) Test Procedure

Total Harmonic Distortion (THD) Test Procedure

equipment list

Suggested

  • A signal generator with the low phase noise option
  • A spectrum analyzer with low phase noise
  • Variable attenuators

Optional

  • Low distortion power amplifier

Test procedure

Bandpass Filters

  • Set the signal generator to the center frequency
  • Adjust the signal level
  • Connect the output of the signal generator to the input of the filter
  • Connect the output of the filter into the variable attenuator (do not overload the input of the spectrum analyzer)
  • Connect the output of the variable attenuator to the spectrum analyzer

Notch Filters

  • The procedure is the same as it is for the Bandpass Filters with the exception of setting the test frequency in the passband of the filter.

Lowpass Filters

  • As above. Use any frequency of interest up to the passband edge.

Highpass Filters

  • As above. Use any frequency of interest up to the passband edge.