The following experimental work shows the results of the relative humidity calculation of a raw ceramic material doped with (CuSO4(ZnO/SnO2 )+H2O), using its frequency response. Due to the ceramic behavior, the chosen frequency range in the experimental process was 1Hz to15 MHz. In the 1Hz to 170 Hz range the material behave as a band - reject filter with central frequency of 84 Hz and then, its behavior change to a band pass filter in the 170 Hz to 13 MHz range with central frequency of 400 kHz.
Key words: Bode diagram, cut frequency, band pass filter, transfer function, relative humidity.