Microwave Engineering Cavity Klystron – Learn Microwave Engineering in simple and Amplification of such two-cavity Klystron is low and hence multi-cavity. Klystron Amplifiers: Description of the function of the Two-Cavity Klystron and the Reflex (Repeller) Klystron. Two-cavity klystron: electron tube: Klystrons: explained in terms of a two-cavity klystron amplifier.
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Additional “buncher” cavities added between the first “buncher” and the “catcher” may be used to increase the gain of the klystron, or to increase the bandwidth. Electrons entering when the entrance grid is negative and the exit grid is positive encounter an electric field in the same direction as their caviry, and are accelerated by the field.
There are frequently numerous regions of ampliifier voltage where the reflex klystron amplifier will oscillate; these are denoted with modes. Some klystrons have cavities that are tunable.
The electrons in this amplifier are excited by an electron gun into one end of the tube. For the generation and amplification of Microwaves, there is a need of some special tubes called as Microwave tubes. Based on the resonant cavities, klystron amplifiers are classified into cavuty types. The electron beam is modulated as it was in the other types of klystrons by twi it through an oscillating resonant cavity, but here the similarity ends.
As the electrons are negatively charged, they are accelerated if moved opposite to the direction of the electric amplifirr. At one end of the tube is the hot cathode which produces electrons when heated by a filament. Retrieved from ” https: The reflex klystron also known as a Sutton tube after one of its inventors, Robert Sutton was a low power klystron tube with a single cavity, which functioned as an oscillator.
If the capacitor is charged with reverse polarity, then the direction of the field is also reversed.
But, these devices are replaced by semiconductor microwave devices. The place is determined by the transit time of the bunches at the cavihy RF of the cavities.
His resonator was called a “rhumbatron” by the Varian brothers. Also, if the electrons move in the same direction of the electric field, they get decelerated. The central part of the structure acts like a capacitor with a hole in it which is where the electron beam can pass through.
Crossed-field klytsron Electromagnetic radiation Free electron laser Gyrotron Inductive output tube Linear accelerator Magnetron Backward wave oscillator Particle accelerator Traveling wave tube Waveguide Extended interaction oscillator. This beam passes through an input cavity resonator.
The buncher grids have an oscillating AC potential across them, produced by standing wave oscillations within the cavity, excited by the input signal at the cavity’s resonant frequency applied by a coaxial cable or waveguide.
Two-cavity klystron | electronics |
The electrons in the beam are velocity-modulated before the beam passes through the cavity the second time and will give up the energy required to maintain oscillations. First let us try to understand the constructional details and the working of a cavity resonator. With the signal applied in the first cavity, we get weak bunches in the second cavity.
A reflex klystron is an obsolete type in which the electron beam was reflected back along its path by a high potential electrode, used as an oscillator. Of them all, Klystron is an important one. The prototype and the demonstration of this amplifier is finished successfully on 30th august and published in the year Here is a question for you, what is the function of Klystron Amplifier? The electrons are focused into a beam by the electrostatic fields set up by the resonator potential U 2 in the body of the tube.
The electrons thus do work on the electric field, and are decelerated, their kinetic energy is converted to electric potential energyincreasing the amplitude of the oscillating electric field in the cavity. Tuning a klystron is delicate work which, if not done properly, can cause damage to equipment or injury to the technician due to the very high voltages that could be produced.
If, however, there exists a structure along the path that can oppose the movement of the electrons, it can cause some of them to reduce their velocity. The displacement of electrons in the tube, constitutes an alternating cavityy.
July 31, by Mark Mitchell Klystron amplifiers are used in a variety of industries, including satellite systems, television broadcasting, radar, particle accelerators, and in the medical field. A whole bunch of electrons behind you got accelerated to a higher velocity and now they are catching up to you as you slow down into them!
At sections far from the optimum voltage, no oscillations are found at all. These bunches enter the second resonator, with a frequency corresponding to the frequency at which the klytsron resonator oscillates. A klystron amplifier is a specific linear-beam vacuum tube, which is used as an amplifier for smplifier resonant frequencies. Electron beam Microwave technology Accelerator physics Vacuum tubes American inventions.
The following figure shows the charge deposition on the capacitor. The reflex klystron contains a reflector plate, referred to as the repeller, instead of the output cavity used klydtron other types of klystrons. Klystron amplification, power output, and efficiency can be greatly improved by the addition of intermediate cavities between the input and output cavities of the basic klystron.
As you have probably surmised being the uber-clever engineer that you arethe alternating signal read: The signal of the amplifier can be amplified amplifieer the energy of the electron beam and the amplified signal can be received from a cavity at the other end of the tube. The field direction changes with the frequency of the Buncher cavity.
It is the interaction of the cavities with the beam that provides the high levels wmplifier amplification that the device can produce. Klystron amplifiers are velocity modulated and high power microwave vacuum tubes which are used as an amplifiers in some radar devices.