60 GHz Gyrotron Development Program. Quarterly report No. 18, October-December 1983

The objective of this program is to develop a microwave oscillator capable of producing 200 kW of CW power at 60 GHz with high purity of the output mode. Power density measurements on the extended 2-1/2 in. collector used in X-8 showed that better magnetic spreading of the beam is necessary to make it a reliable CW collector. This collector was shown to have excellent output mode purity. Work continued on a low-power-density, low-mode-conversion 4 in. collector with satisfactory results. The double-disc window was tested successfully in relatively pure mode TE/sub 02/ at CW power levels up to 76 kW.