Book contents
- Microwave and RF Vacuum Electronic Power Sources
- Reviews
- The Cambridge RF and Microwave Engineering Series
- Microwave and RF Vacuum Electronic Power Sources
- Copyright page
- Dedication
- Contents
- Preface
- Principal Roman Symbols
- Principal Greek Symbols
- Abbreviations
- 1 Overview
- 2 Waveguides
- 3 Resonators
- 4 Slow-Wave Structures
- 5 Thermionic Diodes
- 6 Triodes and Tetrodes
- 7 Linear Electron Beams
- 8 Electron Flow in Crossed Fields
- 9 Electron Guns
- 10 Electron Collectors and Cooling
- 11 Beam-Wave Interaction
- 12 Gridded Tubes
- 13 Klystrons
- 14 Travelling-Wave Tubes
- 15 Magnetrons
- 16 Crossed-Field Amplifiers
- 17 Fast-Wave Devices
- 18 Emission and Breakdown Phenomena
- 19 Magnets
- 20 System Integration
- Appendix: Mathcad Worksheets
- Index
- References
5 - Thermionic Diodes
Published online by Cambridge University Press: 27 April 2018
Book contents
- Microwave and RF Vacuum Electronic Power Sources
- Reviews
- The Cambridge RF and Microwave Engineering Series
- Microwave and RF Vacuum Electronic Power Sources
- Copyright page
- Dedication
- Contents
- Preface
- Principal Roman Symbols
- Principal Greek Symbols
- Abbreviations
- 1 Overview
- 2 Waveguides
- 3 Resonators
- 4 Slow-Wave Structures
- 5 Thermionic Diodes
- 6 Triodes and Tetrodes
- 7 Linear Electron Beams
- 8 Electron Flow in Crossed Fields
- 9 Electron Guns
- 10 Electron Collectors and Cooling
- 11 Beam-Wave Interaction
- 12 Gridded Tubes
- 13 Klystrons
- 14 Travelling-Wave Tubes
- 15 Magnetrons
- 16 Crossed-Field Amplifiers
- 17 Fast-Wave Devices
- 18 Emission and Breakdown Phenomena
- 19 Magnets
- 20 System Integration
- Appendix: Mathcad Worksheets
- Index
- References
Summary
The basis of nearly all types of vacuum tube is the diode in which the electrons emitted by thermionic emission from a cathode are attracted to a positively charged anode. The current through the diode increases as the emitted current increases until it is limited by the negative space-charge of the electrons. The properties of planar, cylindrical and spherical space-charge limited diodes are discussed including the effects of relativity and of the initial thermal velocities of the electrons. When the voltage applied to the anode varies rapidly with time a static solution is no longer valid and transit-time effects must be considered. The properties of diodes in which the electrons are injected with a finite velocity and those in which the electron flow is two-dimensional are reviewed.
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- Microwave and RF Vacuum Electronic Power Sources , pp. 190 - 223Publisher: Cambridge University PressPrint publication year: 2018
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