Transmission lines power measurements for the 110 GHz electron cyclotron heating system on DIII-D and gyrotron operational performance

Operational trends for the six-gyrotron electron cyclotron heating system on DIII-D are presented. Losses in the transmission lines were measured and values close to theoretical were attained for one of the lines with the existing components. Improved alignment and reduction of the number of miter bends in the lines will increase the power transmitted through the waveguide to the DIII-D tokamak.