Umar, LazuardiYanuarEmrinaldi, Tengku2013-04-162013-04-162013-04-16wahyu sari yenihttp://repository.unri.ac.id:80/handle/123456789/2877Abstract— This work present a low cost soil moisture sensor based on impedance spectroscopy by means of magnitude ratio and phase difference detection method. For this purpose, a probe which uses a simpliried impedance measuring system to determine soil water content has been designed. The circuit sweeps at pre-programmed frequencies from 10 KHz to lOMHz with lOmVac amplitude. A local inceptisol soil of East Sumatra was especially selected for this investigatioa because measurements of soil moisture in peat swamp area were generally reported as difficult ones. A sample at defined soil moisture of 2%, %"/», 15% measured using commercial soil sensor Lutron PMS-7i4 was characterized. A corrected model has been developed in order to reject the frequency influence upon the measurement. The results obtained by the sensor show good results with an overall mean error of0.207% in impedance.enSoil moisturesensorimpedancespectroscopyinceptisolmagnitude ratioUR e-Research