General Atomics offers Waveguide Dummy Loads rated for up to 1.2 MW CW (continuous power) input. These loads typically absorb 75%-80% of the power. They are made from a copper-chromium-zirconium alloy and have a stainless-steel water jacket. These compact loads have an extremely low time constant, important for tuning and conditioning the microwave source. These loads have about a 5% bandwidth and have been made for 84 GHz, 110 GHz, 117.5 GHz, 140 GHz and 170 GHz.
Following the waveguide load is a tank load rated for 250-300 kW CW input power. This load absorbs the residual power exiting the waveguide load. These loads are fabricated in aluminum alloy, and can also be supplied in a copper alloy. They are relatively broadband. With optimum input polarization, they can handle up to 400 kW CW.
These loads can also be operated with short pulses. The tank load is rated for 1 MW 0.2 second and 0.5 MW 0.5 second operation as well as 250-400 kW CW.
John Doane, GA-MFE Technologies