Computation of nonreentrant CFA characteristics

The simplified theories of crossed-field interaction only apply to limited zones of the interaction space of practical, high-efficiency CFA\´s. More complete theories need long computer programs to implement them. The aim of this paper is to describe a "pencil and paper" method of computing the characteristics of an operational CFA. At the beginning of the interaction space the gain process is described very accurately by the so-called "small-signal" theories. At the other end of the delay line the energy exchange process and the absorption of the electrons bythe line can be described by a "large-signal" analysis. After calculation of the limits of the small-signal zone and application of Feinstein and Kino\´s theory, the author synthesizes these two aspects of the same phenomenon into a practical method of computation of nonreentrant CFA\´s, and compares the calculations with experiments. As the physical meaning is not lost during this process, a valuable understanding of CFA operation can be gathered by the application of the method. A numerical analysis of the result of the large-signal theory finally shows that in order to obtain the maximum overall efficiency the electronic efficiency has to be matched to the circuit efficiency.