Short-wave radio 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 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 was found.