A klystron has one or more special cavities around the axis of the tube that modulate the electric field. The diamond light source will be the first synchrotron to be operated using iots. Klystron characteristics free download as word doc. The reflex klystron another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron figure 29. Microwave ovens, all about the magnetron, the educational. Travelling wave tube basics, working and applications. The operation of reflex klystron is understood by some assumptions. Our sixpart series on math fact fluency, by explorelearnings vice president of research and development. The electron gun emits the electron beam, which passes through the gap in the anode cavity.
Klystron, thermionic electron tube that generates or amplifies microwaves by controlling the speed of a stream of electrons. Klystron tube article about klystron tube by the free. The reflex klystron operates in a different mode for each additional cycle that the electrons remain in the repeller field. The default filename for the programs installer is stockreflex. In this klystron, a single pair of grids does the functions of both the buncher and the catcher grids. After the focusing electrodes there is a cavity resonator which encircles the glass envelope. This year marks the 60th anniversary of the birth of the klystron at stanford university. Additional cavities serve to velocitymodulate the electron beam and produce an increase in the energy available at the output. Klystron tube, klystron power supply, klystron mount, isolator, frequency meter, variable attenuator, slotted section, tunable probe, vswr meter, waveguide stand, movable shortmatched termination. Microwave engineering cavity klystron tutorialspoint. High performance pulse modulater for 80mw sband klystron. Normally we use separate components in devices such as radio transmitters and receivers but as frequencies increase the two components merge into one structure and become a. The reflex klystron makes use of velocity modulation to transform a continuous electron beam into.
Klystron multi cavity klystron, reflex klystron, working. The most popular versions among filereflex users are 2. The electrons while passing through the anode cavity, gain some. Reflex klystron free download as powerpoint presentation. The shape of the capacitor in the middle of the cavity easily interacts with an electron beam. Piskunov, working as a group, and, independently, by the soviet engineer v. It consists of movable short at one end of the waveguide to direct the microwave energy generated by the klystron tube. Klystron oscillator reflex klystron traveling wave tube biological effect of microwaves. Inductive output tube based 300 kw rf amplifiers for the.
Electron beams are produced from a source and the cavity klystrons are employed to amplify the signals. Another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron figure 29. If you need an oscillator, a reflex tube will work fine, but it is old school technology. The filereflex installer is commonly called filereflex. To study the characteristics of the reflex klystron tube and to determine its electronic tuning range. All these components are enclosed in a glass envelope. Microwave engineering reflex klystron tutorialspoint. The first papers on the theory of the reflex klystron were published by the soviet physicists ia. The essential elements of klystron are electron beams and cavity resonators. The klystron power supply also provides all the other d. Cavity of a repeller klystron another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron repeller klystron. The software lies within business tools, more precisely investmenttools.
The conventional pulse modulator for 80mw klystron have been operated for 11,000hr in the past two years. Reflex klystron vacuum tube manufactured goods free. Observe beam current on the meter by changing meter switch to beam current position. Note in figure that the resonator potential is common to the resonator cavity, the accelerating grid, and the entire body of the tube.
The klystron tube was used for radar systems during the second world war and is still in use for radar systems today. In order to generate microwave frequencies we need amplifiers or oscillators,in this video we will learn how a reflex klystron oscillator works in generation. The reflex klystron contains a reflector plate, referred to as the repeller, instead of the output cavity used in other types of klystrons. The tube was the first practical source of microwaves and its invention initiated a search for increasingly more powerful sources, which continues to this day. The application for klystron with integral cavities is usually credited in the early 1939 to hahn and metcalf and to russell and sigurd varian, two brothers that. The simplest klystron tube is the reflex klystron klystron. They are velocitymodulated tubes that are used in radars as amplifiers or oscillators. A reflex klystron consists of an electron gun, a cavity with a pair of grids and a repeller plate as shown in the above diagram. Caryotakis, performance of a 150mw sband klystron, aip conf. It is of the same rugqedized construction as the bendix 6116tk62 the tube is, division, eatontown, new jersey publication.
A klystron is a vacuum tube that can be used either as a generator or as an amplifier of power, at microwave frequencies klystron types there are two basic configurations of klystron tubes 1. Multi cavity klystron two cavity klystronused as lowpower. In this tube, electrons emitted from the heated cathode travel through the cavity grids toward the repeller plate, then are repelled and returned back the way they came, magnetron tubes. The electrons are fired into one end of the tube by an electron gun.
It is assumed that oscillations already exist in the tube and they are sustained by its operation. Reflex klystron article about reflex klystron by the. Reflex klystron consists of an electron gun, a cathode filament, an anode cavity, and an electrode at the cathode potential. A klystron tube is a special type of vacuum tube invented in 1937 by the varian brothers. 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. Lowpower klystrons are used as oscillators in terrestrial microwave relay. Lowpower klystrons are used as oscillators in terrestrial microwave relay communications links, while highpower klystrons are used as output tubes in uhf television. This software was originally produced by karya technologies, inc. It is a line type pulser because of its wellestablished technology and reliability. As shown in the given diagram it is composed of heater, cathode, focusing electrodes and repeller anode. Reflex klystron oscillator pdf source of an electronbeam and the radiofrequency por tion of the klystron is independent of the electron source. To understand the operation of a reflex klystron i think you need to start with a basic understanding of a tuned circuit made up from a capacitor c and inductor l. The electron beam is modulated as it was in the other types of. Klystron an ultrahighfrequency electronic vacuum device in which a steady stream.
A vacuum tube is a piece of electronic equipment, usually a tubular glass structure, from which most of the air has been removed. Mode 1 is obtained when the repeller voltage produces an electron transit time of 34 cycle. The klystron tube uses electrons in place of air which vibrate on specific frequency inside the glass tube to produce the microwave energy. First, you need to determine what your need for a klystron is. The main difference between two cavity reflex klystron amplifier. The most popular versions among the program users are 9. Single reentrant cavity as a resonator the electron beam.
A microwave source of surprising range and endurance pdf. Since all intermediate cavities in a multicavity klystron operate in the same manner, a. Reflex klystron oscillators have been built which give useful output at frequencies greater than 100,000 mc, or 100 gc. Our antivirus scan shows that this download is clean. A klystron is a specialized linearbeam vacuum tube, invented in 1937 by american electrical engineers russell and sigurd varian, which is used as an amplifier for high radio frequencies, from uhf up into the microwave range. For the generation and amplification of microwaves, there is a need of some special tubes called as microwave tubes. In tv broadcasting on the other hand, inductive output tubes iot are replacing the classical klystron based systems in all new high power uhf transmitters since more than ten years. The principle of velocityvariation, first used in heil oscillators, was also used in other microwave amplifying and oscillating tubes. Voltages required for operation of reflex klystron tube such as beam, heater and reflector voltage. Starting with working memory, we detail the factors involved in developing fluency, its critical role in academic achievement, and how reflex uses this research to great effect. Reflex klystron used as a lowpower microwave oscillator 2. Cathode voltage knob at minimum position gives a beam voltage of 235v. The electron beam is velocity modulated when it first passes through the cavity.
The term velocity modulation refers to change in velocity of electrons as per change in the rf signal. Our software library provides a free download of stockreflex 9. The electrons are originally accelerated to high velocity by a potential of several hundred volts and enter a narrow gap that forms part of a cavity resonator system see figure, where they are acted upon by a radiofrequency field, which causes a bunchingup effect. The brothers russell and sigurd varian of stanford university are the. Reflex klystrons were developed in 1940 by the soviet engineers n. A small hole in the broad wall of the waveguide is provided, through which output coupling pin of klystron tube enters into the waveguide. The magnetic field is only used to focalize the electron beam. In the reflex klystron, the electron beam passes through a single resonant cavity. Sprehn, rettig, peebles and luhmann, of ucla, described experiments in phase locking a 280 ghz backwardwave oscillator and a 140 ghz reflex klystron to a 35 ghz reference. This hole is exactly located in the center of broad wall. Multicavity klystron two cavity klystron amplifier principle velocity modulated tube high velocity electron beam is generated by an electron gun and sent down along a gas tube through an input cavity buncher, drift space field free and an output cavity catcher to a collector electrode anode.