AbstractsBiology & Animal Science


by D. J. Barney

Institution: Central Queensland University
Year: 0
Keywords: Penetrometer.; Soil penetration test.; Soils Testing.; Electromagnetic waves.; Thesis
Record ID: 1052465
Full text PDF: http://hdl.cqu.edu.au/10018/939439


The report presents a discussion on the problems associated with a low frequency carrier system being considered as an alternative to the cable currently used to convey information from the penetrometer cone tip to the surface. Electromagnetic propagation was considered the only feasible alternative to the cable and the main criterion for selecting a frequency of 100 kHz was the attenuation of the signal propagating through the soil. A late decision was made to examine the possibility of a VHF system only when all efforts to produce a low frequency tuned antenna to satisfy the physical space requirements had failed. Further work is required on the VHF antenna as an alternative, as time did not permit tests to be carried out with the antenna 20 m or more below the surface.