This database table is the Dixon Master List of Radio Sources (Version 43, dated November 1981) which contains flux densities for known radio sources detected at a variety of frequencies. The Master List of Radio Sources was prepared by combining about thirty catalogs of radio sources that were available as of that date into a common format. Notice that this is a list of observations, not of individual sources, and that an entry in this table corresponds to an observation of a radio source at a particular frequency from a particular source catalog: also, no attempt was made by the author to use the same name for the same source, e.g., the source 3C 273 appears more than a dozen times under a variety of names such as PKS 1226+02, NRAO400, CTA 53, etc. This database table was recreated at the HEASARC in June 2005 after it was discovered that the positions had been incorrectly precessed. The original input table used for both the previous and current HEASARC Dixon tables was the 43rd version of the Master List, dated November 1981. It was obtained from the Colorado node of the Astrophysics Data System (ADS), the now-defunct HTTP link <adswww.colorado.edu/catalogs/rad_msl43.html>, and apparently was provided by D. E. Harris on or after 1991. Notice that the version of this table that is currently available at CDS (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/2A">https://cdsarc.cds.unistra.fr/ftp/cats/VII/2A</a>) is, according to Andernach (1989, Bull. Inf. Centre Donnees Stellaires, 37, 139), the 42nd edition (dated 1976) and has only 79493 entries compared to 84510 entries in the HEASARC table. 49 duplicate entries were removed from the HEASARC table in June 2019. This is a service provided by NASA HEASARC .