Comparison of Tropospheric Reception at 44.1 Mc with 92.1 Mc over the 167-Mile Path of Alpine, New Jersey, to Needham, Massachusetts

In a previous work (1947) the authors rendered an account of field intensity measurements of W2XMN at 42.8 Mc made at the Cosmic Terrestrial Research Laboratory at Needham, Mass., during 1945 and a part of 1946, and exhibited certain relations found with meteorological conditions. On January 24, 1947, the frequency of W2XMN was changed from 42.8 Mc to 44.1 Mc, and in the summer of that year a higher frequency was transmitted from the same tower at Alpine as station W2XEA at a frequency of 92.1 Mc, with substantially equal power on both frequencies. This gave an opportunity for making comparative measurements on both the higher and lower frequencies over the same path of Alpine, NJ, to Needham, Mass., 167 miles in length, or 270 kilometers. Plotted values of relative fields in log microvolts/meter are exhibited in weekly means on the accompanying diagram for both W2XMN and W2XEA together with the calculated surface refraction over the interval from August, 1947, to December, 1948.