Electron Tubes, General Specification for FSC 5960 This specification covers the general requirements and ratings for electron tubes used by the military departments. Categories of tubes covered include, Beam Switching, Cathode Ray, Cathode Ray Charge Storage, Cold Cathode, Corona Voltage Regulator, Cross Field Amplifier, Electron Multiplier, Electron Ray Indicator, Gas Switching, Graphic Indicator, Gyrotron, Ignitron, Image Converter, Image Orthicon, Klystron, Magnetron, M-Type Backward Wave, Negative Grid (microwave), Noise Source, O-Type Backward Wave, Phototube, Power or Transmitting, Pulse Modulator, Radiation Counter, Receiving, Stabilotron, Thyratron, Traveling Wave (or forward wave), Vidicon, and Voltage Regulator.
http://www.dscc.dla.mil/Programs/MilSpec/ListDocs.asp?BasicDoc=MIL-PRF-1
