DID YOU KNOW? DTIC has over 3.5 million final reports on DoD funded research, development, test, and evaluation activities available to our registered users. Click HERE
to register or log in.
APPLIED RESEARCH ON EFFICIENCY IMPROVEMENT IN O-TYPE TRAVELING-WAVE TUBES.
HUGHES AIRCRAFT CO LOS ANGELES CALIF
A single velocity-step taper has been tested in the demountable apparatus. Improvements of the electronic efficiency of nearly 30 over that of the standard circuit were observed, while the depressed efficiency was about the same. A design evaluation of the taper section on the basis of a large-signal computer analysis for step tapers showed good qualitative agreement with predictions. The step-taper was estimated to be too large, while it had about the correct velocity step magnitude for the test conditions. Investigations indicate that at lower beam perveances the beam flow appears to change from a highly non-laminar to a much more laminar Brillouin flow. At low beam perveances and apparent laminar flow conditions the efficiency is significantly increased. At these conditions efficiencies up to 50 were observed. At frequencies near the lower cutoff a beam loading effect in the circuit properties was noted. The tube parameters are then considerably changed from those obtained with cold circuit measurements. An accurate spent beam velocity analyzer has been developed for detailed efficiency evaluations. The effects of the electrostatic potential distribution, the secondaries and the space charge on the accuracy of the analyzer are discussed. The beam analyzer also provides electron optical information about the beam. Author
Interim engineering rept. no. 2, 15 Oct 64-15 Jan 65.
See also AD-608 930.
AF33 615 1951