The work has been mainly concerned with the construction and R. F. testing of Design no. 1 and no. 2 magnetrons. R. F. operation has been obtained in both designs over good bandwidths, but frequency of operation is on the low end of the desired range. Circuit work has also been initiated and used in conjunction with the two designs under investigation. The successful operation of a Design 2 tube over a wide frequency range is of major consequence to this program. It represents confirmation of the basic ideas of the novel approach that has been used, particularly in the coupling scheme. The R. F. operation also means that the technology is also becoming resolved for this new approach. Refinements in technology and design are the main area for emphasis and these follow analysis of experimental models. Operation of Design 1 and previous 8 vane anode tubes in comparison with 7 vane tubes and lower frequency tubes indicates that further research effort into the higher vane tubes is warranted, particularly in the areas of injection and transition.