What is klystron oscillator?
The Klystron is a vacuum tube which used as an oscillator and amplifier of microwave signals. The magnetron is different from the klystron tube. The magnetron used only as an oscillator. In a klystron, the electron is injected normally from the cathode.
Are klystrons still used?
It was used as a local oscillator in some radar receivers and a modulator in microwave transmitters in the 1950s and 1960s, but is now obsolete, replaced by semiconductor microwave devices. In the reflex klystron the electron beam passes through a single resonant cavity.
How do klystrons produce microwaves?
klystron, thermionic electron tube that generates or amplifies microwaves by controlling the speed of a stream of electrons.
Who invented the klystron?
Sigurd Fergus Varian
Russell Harrison Varian
Klystron/Inventors
What is cavity in klystron?
A focused beam of electrons is thus produced. In the case of the two-cavity klystron, the electron beam passes through a central hole in the first toroid-shaped cavity and through a similar second cavity, terminating at the collector.
What is velocity modulation in klystron?
In the reflex Klystron tube, velocity modulation takes place near the accelerating grid. Velocity modulation is a variation of velocity of the electron beam. It allows the passage of an electron beam through a resonant cavity.
What is two cavity klystron?
The two-cavity klystron utilizes an electron source (heater), an anode, and a cathode like a conventional vacuum tube. It also utilizes a collector element at the end of the electron stream.
What is bunching in klystron?
The klystron utilizes a phenomenon called electron bunching which goes as follows: Electrons in a beam leaving a source at high velocity all have a roughly equal velocity in the direction of travel.
What is the frequency range of klystron?
At frequencies between about 100 and 1000 MHz, a hybrid tube, part triode, part klystron, has promise. Called a Klystrode™, it was invented in 1939 and demonstrated at low power levels, but lay dormant for over 40 years.
What are the applications of klystrons in local oscillators?
smaller repeller klystrons (as shown in Figure 8) have been used as stable local oscillators in measuring amplifiers and receivers because they can be easily tuned in frequency in a small range. Applications of W-Band klystrons are currently the subject of laboratory research.
How is an electronic oscillator made from klystron tubes?
An electronic oscillator can also be made from a klystron tube when the second cavity resonator is fed back to the first one with a coaxial cable or waveguide. This connection must have a defined delay so that the oscillations are in phase.
What is the power output of a klystron?
The average output power is up to 500 kW and pulsed power is up to 30 MW at 10 GHz. The power amplification is up to 30 dB. 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.
How does a klystron amplifier work?
Klystron amplifiers amplify the Rf signal. It converts the kinetic energy of the signal in a DC electron beam into the RF power. Inside a vacuum, an electron gun emits a beam of electrons, and the high-voltage electrodes accelerate the electron beam.