Abstract: A variable absorptive/reflective high power attenuator for attenuating microwave signals in a communication system is formed from a circulator connected to a section transmission line such as a waveguide, having at least one adjustable tuning element connected thereto. The transmission line itself is terminated with a microwave energy absorbing load. A signal injected into the circulator is partially reflected by the tuning element(s), and partially absorbed in the load. The reflected portion is routed to an output port of the circulator. The non-reflected portion is dissipated as heat by the load. The amount of output of signal attenuation is selectively controlled by the location and penetration of the tuning elements. In another embodiment, a latching type circulator is utilized to allow selective switching of the attenuation level insitu. More than one such switching type attenuator can be cascade connected to form a single customizable and variable attenuator design.