Wadley, T. L.2015-07-102015-07-102015-07-10http://hdl.handle.net/10539/18064Thesis (D.Sc.)--University of the Witwatersrand, Faculty of Science, 1959.enRadio--Equipment and suppliesRadio--Receivers and reception--Heterodyne receptionTellurometerIonospheric radio wave propagationHeterodyne techniques in specialised radio instrumentationThesis