A rigid mount orbitor sprinkler assembly incorporates a deflector plate configuration that is configured for both spinning/rotating motion as well as orbital or wobbling motion around the center of a spool assembly. The sprinkler incorporates structure to reduce drool that may fall in a concentrated area below the sprinkler and to prevent debris from sandy water or the like from accelerating sprinkler component wear. With reduced vibration, the assembly may be rigidly mounted on a center pivot or other supporting structure while achieving the advantages associated with wobbling and rotating sprinkler assemblies.