Deviations of Short Radio-Waves from the London-New York Great Circle Path

Abstract

THE propagation of short radio-waves from England to New York has been found to involve many anomalous effects. Studies have been made of transmissions from Rugby, directed toward New York, and of broadcasts from Daventry using various transmitting arrays. Three multiple unit steerable antennæ (musas) located at the Holmdel, N.J. experimental receiving station of the Bell Telephone Laboratories have been used. One of these is the end-on musa described in a recent paper¹. The other two are broadside musas steerable horizontally to permit explorations in azimuth. The British Broadcasting Corporation has kindly provided details of the transmitting antennæ in use during the various transmissions. These B.B.C. antennæ, together with the British Post Office transmitting antennæ in use on the London–New York radio telephone circuits, have provided simultaneous comparisons, which are, to a limited degree, representative of the effects of steerable transmitting directivity. Employment of the above facilities during the past eight months has disclosed the following characteristics: (1) During âall-daylightâ path conditions, the usual multiplicity of waves distributed in or near the great circle plane, which constitutes normal propaga tion, has invariably been predominant. Neither ionosphere storms nor the catastrophic disturbances associated with short-period fade-outs seem to affect the mode of propagation.