Fig. 8. Bulk permittivity of Millville silt loam and sand determined using scatter function fitting (SFF) in the frequency domain and travel time analysis (TTA) in the time domain given as a function of soil solution electrical conductivity. To illustrate the effect of signal attenuation on permittivity determination, probe lengths of 2, 3, 6, 10, and 15 cm were used (note: 10-cm probe was not used in sand).