1. Operational Problems
       a. RF System Vacuum Trips
       b. Tuner Vacuum Leaks
       c. Overheated Tuner Flanges
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2. Internal Evidence
       a. Arc Track Marks on Tuner Piston
       b. Arc Track Marks on Cavity Port
      c. Damaged Tuner Piston Braze Joints
   --
3. Causes
       a. Poorly Aligned Tuner Piston
       b. Non-Uniform Piston-Housing Gap
   --
4. Solutions
       a. Mechanically Align Tuner Piston
       b. Remachine Housing/Piston Gap
       c. Ti-Coat Tuner Piston to Reduce Multipactor
   --
5. Modular Tuner Redesign Implementation
       a. No Welding in Final Assembly
       b. Align Tuner Piston Within Housing
       c. Continue Ti-Coating Tuner Piston
       d. Contact Fingers Under Development,
           (Presently Using Ag-Plated Be-Cu Fingers)

Damaged RF Cavity Port

Damaged Ti-Coated Tuner
(Piston not centered)