Coaxial cavity microwave oscillator with manually adjustable capacitive feedback element

In a microwave oscillator of the type including an active device in a coaxial package comprising an input coaxial RF resonator and an output coaxial RF resonator with a common conductive wall separating the input and the output resonators, said active device including an input, an output and a common electrode with the common electrode coupled to the common wall, the input electrode coupled to the center conductor of the input resonator and the output electrode coupled to the center conductor of the output resonator, the improvement therewith for providing adjustable feedback comprising:

• a wire-like coupling member of rigid conductive material connected at one end to the center conductor of the input resonator and extending in insulative manner through said common wall to a point closely spaced from the center conductor of the output resonator,
• a sheet of conductive material fixed to the free end of said wire-like coupling member with said sheet closely spaced from the center conductor of said output resonator to provide capacitive coupling therewith, said sheet being thin and of a deformable material to permit the ends of said sheet to be easily bent toward and away from the center conductor of said output resonator to easily adjust the capacitive coupling provided by the sheet without disturbing the support provided by the wire-like coupling member.