Sometime back, All India Radio used to broadcast to U.K. between 1300 and 1400 IST (IST-GMT+ 5#xbd; hours). During the years 1953 and 1954, when the sunspot activity was at its minimum, the optimum bands worked out to be quite low. In actual practice, bands higher than OWP and even MUF for F2-layer transmission were found to provide reliable reception at the target area. This paper deals with the mechanism which might have been responsible for such reliable transmission on higher bands. It is observed that propagation through Esplayed an important part in providing a satisfactory service on bands higher than classical MUF.
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