Author: Naranjo, A.C.
Paper Title Page
TUP135 RF Design and Operating Results for a New 201.25 MHz RF Power Amplifier for LANSCE 1091
 
  • J.T.M. Lyles, N.K. Bultman, 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 prototype VHF RF Final Power Amplifier (FPA) for Los Alamos Neutron Science Center (LANSCE) has been designed, fabricated, and tested. The cavity amplifier met the design goals producing 3.2 MW peak and 480 kW of average power, at an elevation of 2.1 km. It was designed to use a Thales TH628 Diacrode®, a state-of-art tetrode power tube that is double-ended, providing roughly twice the power of a conventional tetrode. The amplifier is designed with tunable input and output transmission line cavity circuits, a grid decoupling circuit, an adjustable output coupler, TE mode suppressors, blocking, bypassing and decoupling capacitors, and a cooling system. The tube is connected in a full wavelength output circuit, with 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. We summarize the design processes and features of the FPA along with significant test results. A pair of production amplifiers are planned to be power-combined and installed at the LANSCE DTL to return operation to full beam duty factor.
 
 
TUP133 Mechanical Design and Fabrication of a New RF Power Amplifier for LANSCE 1085
 
  • Z. Chen, M.J. Borden, N.K. Bultman, C.A. Chapman, J. Davis, J.L. Ferris, T.S. Gomez, J.T.M. Lyles, A.C. Naranjo
    LANL, Los Alamos, New Mexico, USA
  • D. Baca, R.E. Bratton, R.D. Summers
    Compa Industries, Inc., Los Alamos, New Mexico, USA
 
  Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
A Full-scale prototype of a new 201 MHz RF Final Power Amplifier (FPA) for Los Alamos Neutron Science Center (LANSCE) has been designed, fabricated, assembled and installed in the test facility. This prototype was successfully tested and met the physics and electronics design criteria. With a goal to produce 3.2 MW peak power at 15% duty factor, at the elevation of over 2 km in Los Alamos, The team faced design and manufacturing challenges. The mechanical design of the final power amplifier was built around a Thales TH628 Diacrode®, a state-of-art tetrode power tube*. The main structure includes Input circuit, Output circuit, Grid decoupling circuit, Output coupler, Tuning pistons, and a cooling system. Many kinds of material were utilized to make this new RF amplifier. The FPA is nearly 1000 kg and installed in a beam structural support stand. In this paper, we summarize the FPA design basis and fabrication, plating, and assembly process steps with necessary lifting and handling fixtures. In addition, to ensure the quality of the FPA support structure a finite element analysis with seismic design forces has also been carried out.
* J. Lyles, S. Archuletta, N. Bultman, Z. Chen, et al., “Design of a New VHF RF Power Amplifier System for LANSCE”, IPAC’10, Kyoto, Japan, May 24-28, 2010.