Short-Wave Transmission to South America

The results of a year's survey of transmission conditions between New York and Buenos Aires in the short-wave radio spectrum are presented in this article. Surfaces showing the received field strength as a function of time of day and frequency are given. These show that frequencies between 19 and 23 megacycles were best for daytime transmission, and those between 8 and 10 megacycles for nighttime transmission. A transition frequency was required in the early morning, but the useful periods of the day and night frequencies overlapped in the evening. No variations that could definitely be traced to a seasonal effect were found. This path is much less affected by solar disturbances than the transatlantic. Frequencies above 30 megacycles appear to have but little commercial value over this path. Frequencies a few megacycles higher could not be received.