In order to increase a service life of a microwave generator, a resonator configuration for a microwave generator has a hollow cylindrical electrical conductor positioned inside a housing, a first electrode, and a second electrode. Two electrodes are spaced apart from one another and form a spark gap in the region of the conductor. A contact element is provided for making electrical contact between the conductor and the first electrode. The position of the first electrode can be adjusted to modify a length of the spark gap. Furthermore, the contact element is electrically connected to the first electrode or its holder so as to resist movement so that the opposing contact surfaces remain in contact even when the position of the first electrode is adjusted with respect to the second electrode. The contact element is configured to be deformable, preferably elastically deformable, for this purpose.