This supplement was written for the purpose of extending the scope of the original paper, by providing a more complete set of system-performance design equations, which apply to the Frequency Division Multiplex--Frequency Modulation type of multichannel telecommunication systems; these equations may be used for various types, and combinations of types, of message signals. The page numbers of this paper correspond to the pages in "The National Bureau of Standards Technical Note 100", on the topic of FDM-FM systems-performance calculations, based primarily on the FM radio receiver transfer function. The referenced page numbers and equation numbers in this paper refer, of course, to NBS Technical Note 100.

A survey of some of the advances in the field of synoptic radio meteorology is presented. The development of representative refractive index profiles for major air mass types is reviewed. Included is a description of several refractive index parameters currently in use by radio meteorologists. Two reduced-to-sea-level index forms developed at the National Bureau of Standards are used to illustrate the three-dimensional structure of a broad-scale storm system traversing the North American continent.

This supplement was written for the purpose of extending the scope of the original paper, by providing a more complete set of system-performance design equations, which apply to the Frequency Division Multiplex--Frequency Modulation type of multichannel telecommunication systems; these equations may be used for various types, and combinations of types, of message signals. The page numbers of this paper correspond to the pages in "The National Bureau of Standards Technical Note 100", on the topic of FDM-FM systems-performance calculations, based primarily on the FM radio receiver transfer function. The referenced page numbers and equation numbers in this paper refer, of course, to NBS Technical Note 100.