On the Influence of Solar Activity on Radio Transmission

The paper describes further examination of the daylight long wave signal measurements of the Bureau of Standards for evidence of correlation with solar activity. It has already been shown that a probable correlation exists between signals and sunspots when the observations are continued for several years and are averaged in periods of a month or more. The present paper deals especially with observations averaged in shorter (5-day) periods. Here while the relationship is generally evident it is sometimes obscured by an apparent relative phase shift between the signal and sunspot curves.