用锯齿扼流使微波炉的辐射泄露最小:The serrated choke provided the needed low impedance
at the circumferential, narrow-wall slots of two
coupled annular waveguide rings for a rotary joint.
This choke design was found to be
economical to manufacture, very reliable, and very tolerant of the
spacing between door and oven chamber.
实际的东西啊