Characteristics of Argon Noise Source Tubes at S-Band (Correspondence)

During the design of equipment for applications in radio astronomy, various tests were performed on argon plasma noise source discharge tubes, with emphasis on the Bendix 6358/TD-12 which is Model A148 of Johnson and DeRemer. In view of the wide use of these tubes as secondary standards of microwave noise power, a brief summary of the results obtained will be given. A description of the test equipment and experimental procedures used would be repetitive of much that has been reported by Sees and Hughes, but is available from the writer if desired.