Development program for a 200 kW, c-w gyrotron. Quarterly report No. 8, April-June 1981

The objective of this program is the design and development of a millimeter wave device to produce 200 kW of continuous-wave power at 60 GHz. The device, a gyrotron oscillator, will be compatible with power delivery to an electron-cyclotron plasma. Smooth control of RF power output over a 17 dB range is required, and the device should be capable of operation into a severe time-varying load mismatch. The first tube was assembled and vacuum processed during this quarter. However RF evaluation was postponed because of a superconducting solenoid malfunction. The emission quality of a gun tester was confirmed. The gun tester was then used to check out a cathode modulated pulser and resistor grid divider. The first phase of the Gyrotron Test Facility was completed when the vacuum processing equipment and short pulse modulator were brought on-line. The second Facility phase was started with the reassembly of the medium pulse (100 ms) modulator