95 GHz gyrotron with water cooled magnet and high average power

A 95 GHz gyrotron with water cooled copper magnet delivering high average power was assembled. The cavity interaction mode is TE 02 at the second cyclotron harmonic. Internal mode converter is used to convert the interaction mode to quasi-Gaussian mode at the gyrotron output window. $\mathrm {A}\sim 1.8\mathrm {T}$ magnetic field is produced by water cooled copper electromagnet. The magnet and the gyrotron have immediate turn on and off time when the cathode is worm $( \lt 1\mathrm {s})$. Initial results will be presented.