Field Strength Measurements at Ahmedabad of Short Wave Radio Signals from ‘Radio Sri Lanka’, Colombo, on 11·8 MHz

Abstract

In this paper, results are reported on the studies of the variations in the field intensity of short wave radio signals. An automatic equipment was set up at Ahmedabad (23°01'N, 72°36E; I = 34°N) in July 1966 for recording field strength of short waves transmitted on 11·8 MHz from Colombo (06°54'N, 79°52'E; I = 5°S). The aims of this experiment were to obtain an average diurnal and seasonal variation of the short wave field intensity for a transequatorial propagation over a distance of about 2000 km and to report on some events like SID and SWF. Some typical day-time and night-time records of signal strength are presented, and the results obtained for the two years 1966–68 are discussed.