dependent oscillations are the result of a competition between chemical pumping and radiative deactivation of the upper laser levels of HF due to lasing. The oscillations occur only if the medium is not strongly coupled to the optical fields diffractively or geometrically. Three new experiments were suggested to verify the proposed mechanism by varying the geometric and diffractive coupling of the optical field to the gain medium. 5,6 In this study, the proposed mechanism is tested by performing the three proposed experiments using the UIUC cw HF supersonic chemical laser. Time-dependent oscillations may decrease the average total power that may be extracted from high-energy chemical laser unstable resonators. The need to maximize performance of such systems motivates the study of the time-dependent oscillations.