The theory can readily be extended to other frequencies and waveguide dimensions. ...  K. Noda, K. Yamaguchi, and N. Suzuki, aquot;Circular electric wave transmission through helix waveguide, aquot; Review of the Electrical Communication Laboratory, vol. ... 115-211.  R.E. Collin, Field Theory of Guided IVaves. New York: McGn Hill, 1960.  S. B. Cohn, aquot;Determination of ...  A. Parrish, Instruction Manual for VLA Circular Waveguiit 7i Set, NRAO Report, Green Bank, WV, Sept. 1974.