An interpretation of vertical incidence equivalent height versus time recordings on 150 kc/s

Results of virtual height versus time vertical incidence pulse recordings, obtained on 150 Kc/s, are presented and discussed. Monthly median values of the reflection heights are shown in a series of graphs. The coupling echo, predicted by current wave theory, is definitely shown to exist. The results of measurements during undisturbed and disturbed days are discussed. It is concluded that one form of echo regularly noticed during magnetically disturbed nights must be due to one type of sporadic E. Recorded group and phase heights are compared and the differences checked against those predicted theoretically. Finally, the results are given of a preliminary investigation of the effects of solar flares.