
%0 Journal Article
%A Strohfeldt, M 
%A McNicol, RWE 
%A Gipps, G de V 
%T Ionospheric Measurements at Oblique Incidence over Eastern Australia
%J Australian Journal of Chemistry
%D 1952/09/01
%V 5
%N 3
%P 464-472
%K 
%R https://doi.org/10.1071/CH9520464
%U https://www.publish.csiro.au/paper/CH9520464 
%X An account is given of night observations of oblique-incidence pulse transmissions on 5.8 Mc/s. over a baseline of 763 km., using a responder technique. The experiment aimed at measuring apparent path lengths as a guide to the identification of the reflecting layer in the ionosphere. The characteristics of beacon triggering are discussed in relation to the echo system received after ionospheric reflection.   A correlation of Es occurrences as observed at oblique incidence and vertical incidence near the midpoint of the trajectory was effected, and certain characteristics of the Es layer are presented. Unusual records of Pedersen rays are reproduced and sudden height increases and diffuseness of F2 echoes are discussed.   A check on the oblique-incidence theory using a Millington transmission curve on vertical-incidence h'f records yielded reasonable agreement between measured and deduced reflection heights, although there is evidence of a tendency for the predicted obliquity factor to be too low. A rough analysis of oblique-incidence penetrations yielded an average value for the frequency separation of the magneto-ionic M.U.F.'s close to half the gyromagnetic frequency. 
