A new H10-to-H20 mode transducer

Using a general method of mode-transducer design previously described, a simple H10-to-H20 mode transducer was constructed. The reflection coefficient is calculated, and it is shown that for a transducer a few wavelengths in length the reflections are insignificant. The power transferred to the spurious modes was measured by the resonance method on two experimental models, 2 and 8 guide-wavelengths long. The longer transducer transforms 92% of the power into the required mode. The power in unwanted modes can be greatly reduced by the use of a simple absorptive mode filter.