High power CW, octave bandwidth traveling wave tubes using brazed helices

The CW power level of octave bandwidth helix type traveling wave tubes can be increased by an order of magnitude by brazing the helix support rods to the helix and to the tube shell to obtain good thermal contact. Two traveling wave tubes utilizing such brazed helices will be described: a 2000-watt CW, solenoid focused, 2-4 GHz tube, and a 500-watt CW, PPM focused, 4-8 GHz tube. Features of the electrical and mechanical design and test results will be presented.