Reflex klystron article about reflex klystron by the. The reflex klystron another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron figure 29. What is probably the primary advantage of the reflex klystron over the twocavity klystron is the mechanism used to tune the device. The velocities of electrons emitted from the cathode are modulated to produce a densitymodulated electron beam. A klystron is a specialized linearbeam vacuum tube, invented in 1937 by american electrical engineers russell and sigurd varian, which is used as an. These include the two cavity amplifier or oscilator, the reflex klystron, and the multicavity high power amplifier. Study of the characteristics of the klystron tube objective to study the characteristics of the reflex klystron tube and to determine the its electronic tuning range equipments klystron power supply, klystron with mount, isolator, frequency meter, variable attenuator, xband detector, bnctobnc cable and oscilloscope theory. To study the mode characteristics of the reflex klystron tube and to determine. This is the reflex klystron oscillator, which will now be described.
Twystron is a hybrid amplifier which uses a combination of klystron and slow wave structures. After the focusing electrodes there is a cavity resonator which encircles the glass envelope. The reflex klystron contains a reflector plate, referred to as the. It is known by this name due to its reflex action of electron beam. The reflex klystron makes use of velocity modulation to transform a continuous electron beam into. Typical operational problems with a klystron input drive power is too low and klystron is not saturated although this is required if the tube is included in a feedback loop reduced output power, efficiency, and increased output power amplitude jitter wrong cathode filament current wrong perveance. Microwave engineering ece questions and answers page 2. It was used as a local oscillator in some radar receivers and a modulator in microwave transmitters the 1950s and 1960s, but is now obsolete, replaced by semiconductor microwave devices. The average power output of this tube is about 70 mw. The dependence of these characteristics on the beam current, beam voltage, re flector voltage, load, and other klystron design factors. Reflex klystron free download as powerpoint presentation.
A singlecavity klystron in which the electron beam is reflected back through the cavity resonator by a repelling electrode having a negative voltage. Now understand the concept of reflex klystron in microwave engineering in details through following questions and answers. An electron beam is formed in an electron gun and passed through the gaps associated with the two cavities fig. Microwave engineering reflex klystron tutorialspoint. Ph0101 unit 2 lecture 6 2 reflex klystrons the reflex klystron has been the most used. View and download powerpoint presentations on two cavity reflex klystron ppt. 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. Reflex klystron oscillator operation application of.
As shown in the given diagram it is composed of heater, cathode, focusing electrodes and repeller anode. Microwave engineering cavity klystron tutorialspoint. The brothers russell and sigurd varian of stanford university are the. Figure 9 shows a reflex klystron commonly used in microwave equipment. Reflex klystron used as a lowpower microwave oscillator 2. What is the difference between the two cavity klystron. This microwave generator, is a klystron that works on reflections and oscillations in a single cavity, which has a variable frequency. All these components are enclosed in a glass envelope. It is possible to produce oscillations in a klystron device which has only one cavity, through which electrons pass twice. The 2k28 reflex klystron has a lead protruding through the top of the glass envelope which is used to connect the reflector voltage to the tube. Find powerpoint presentations and slides using the power of, find free presentations research about reflex klystron. On this channel you can get education and knowledge for general issues and topics. It has two microwave cavity resonators the catcher and the buncher. Reflex klystron working, oscillator and applegate diagram.
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. It is given the name reflex klystron because of its reflex action of electron beam. The reflex klystron utilizes velocity modulation to convert regular electron beam energy into microwave power. Difference between two cavity klystron and reflex klystron. A reflex klystron is oscillating at the frequency of its resonant cavity. Microwave communication questions and answers pdf free download for ece mcqs objective type interview questions lab viva manual gate cat syllabus. Reflex klystron working free download as powerpoint presentation. For proper working as an oscillator the output voltage needs to be fed back to the input and if positive feedback is taken then only the klystron will oscillate. This name is given by the name of its inventor robert sutton, it allow the passage of electron beam through a single resonant cavity. Optimization of micromachined reflex klystrons for operation at. A klystron is a specialized linearbeam vacuum tube evacuated electron tube the name klystron comes from the stem form.
Slow wave structures are also otype but have nonresonant periodic structures for electron interactions. Reflex klystron working, oscillator and applegate diagram youtube. The reflex klystron oscillator is a lowpower, lowefficiency microwave oscillator, illustrated schematically in figure 118. In this klystron, a single pair of grids does the functions of both the buncher and the catcher. Microwave engineering cavity klystron for the generation and amplification of microwaves, there is a need of some special tubes called as microwave tubes. Klystron multi cavity klystron, reflex klystron, working. Twocavity klystron amplifier 62801 circuit and wiring. Series attempts to cover the basic principles underlying the operation of klystrons and planar grid tubes as oscillators and amplifiers.
Reflex klystron consists of an electron gun, a cathode filament, an anode cavity, and an electrode at the cathode potential. So basically what was the need for reflex klystron when we had multicavity klystron. Yenkapally, moinabad mandal himayathnagar post, hydreabad75. The difference between reflex and twomulti cavity klystron is that, reflex klystron uses single cavity for modulationdemodulation. Reflex klystron amplifier, microwave klystron amplifier slideshare. Different characteristics of reflex klystron can be determined using the whole associated package for reflex klystron experiments. The conventional vacuum tubes, such as triodes, tetrodes, and pentodes, are.
Find powerpoint presentations and slides using the power of, find free presentations research about two cavity reflex klystron ppt. The reflex klystron contains a reflector plate, referred to as the repeller, instead of the output cavity used in other types of klystrons. Klystron power supply, klystron tube, isolator, frequency meter, variable attenuator, detector mount, waveguide stand, vswr meter and bnc cable. Pdf study of a reflex klystron emmanuel markoulakis. Important question and answers on reflex klystron with. Home communication systems reference and training manuals figure 8.
If the reflector voltage is made slightly less negative, the. Klausst 72fvm 36betwixt 22 reflex klystron, volker muehlhaus 21asdf44 the process is referred to as modulation. Reflex klystron reduced power from the bunches, in reflex klystron, reduces the reflex klystron of the cavity oscillations and causes a decrease in output power. And the another difference is that in twocavity klystron at this place there is a collector which is used to collect the electron beam coming from the output cavity. Reflex klystron oscillators ieee xplore a reflex klystron oscillator.
View and download powerpoint presentations on reflex klystron ppt. Reflex klystron amplifier, microwave klystron amplifier. A loop coupling is used inside the cavity to get the output. To study the characteristics of the reflex klystron tube and to determine its electronic tuning range. To study the characteristics of reflex klystron to study the characteristics of reflex klystron.
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