Applications of the cathode for millimeter wave tubes

The cathode discussed has been applied to millimeter wave tubes and yielded good results. There were two types of tubes, whose designed parameters were the pulse output power of 60 W and 80 W. Both types of tubes have achieved the output parameter. The tubes are appraised. The other two types of tubes required the pulse output power of 400 W and 4,000 W; the former reached 200 W, the latter reached 2,600 W, or 3,000W at low duty ratio. In the above tubes, the diameter of the electron beam is 0.8-1.2 mm. At present the transmissivity has reached 92-98% with a current density of 8A/cm²