A high power waterload was developed for use with Gaussian mode gyrotrons p
roducing output powers up to 1.25 megawatt (MW) CW between 70-170 GHz. This
paper describes the electrical and mechanical design and provides the resu
lts of initial tests on a gyrotron at 110 GHz. The load uses a rotating ref
lector and a tapered dielectric loss coating to control the power absorptio
n within the cylindrical structure. Test results indicate that the load may
be capable of significantly higher power levels than anticipated and that
the load may be able to reliably dissipate power levels approaching 2 MW CW
.