Author: Naranjo, A.C.
Paper Title Page
THPPC069 Design, Test and Implementation of New 201.25 MHz Power Amplifier for the LANSCE Linac 3446
  • J.T.M. Lyles, Z. Chen, J. Davis, A.C. Naranjo, D. Rees, G. M. Sandoval, Jr.
    LANL, Los Alamos, New Mexico, USA
  • D. Baca, R.E. Bratton, R.D. Summers
    Compa Industries, Inc., Los Alamos, New Mexico, USA
  • N.W. Brennan
    Texas A&M University, College Station, Texas, USA
  Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
A new 201.25 MHz final power amplifier (FPA) has been designed, fabricated, and tested at Los Alamos Neutron Science Center (LANSCE). The prototype FPA has produced 3 MW peak and 250 kW of mean power with 15 dB of power gain and over 60% efficiency. It has been tested for several thousand hours with a load. A Thales TH628 Diacrode® electron tube is key to the performance of the new amplifier. It is configured with a full wavelength output circuit, having the lower main tuner situated ¾λ from the central electron beam region in the tube and the upper slave tuner ¼λ from the same point. The FPA is designed with input and output transmission line cavity circuits, grid decoupling circuits, an adjustable output coupler, DC blocking and RF bypassing capacitors, HOM suppressors, and a cooling system. A pair of production amplifiers are planned to be power-combined for up to 3.6 MW peak power at high duty factor. Three of these combined amplifiers will be installed in place of the original 1968-vintage amplifiers to return LANSCE operation to 12% beam duty factor with higher peak current than presently possible.