Experiments involving mirror transponders in rotating frames

Abstract
Two experiments are described in which mirrors were mounted on rotating turntables and measurements were made of the frequency of the reflected radiation. The order of accuracy was one part in 1017, which exceeded that required to detect second-order relativistic phenomena. It is shown that the mirrors are equivalent to transponder systems and that the application of logical arguments to the telemetered observations confirms earlier theoretical predictions of the radius and angular velocity of a rotating system measured entirely from a point within that system.