Microwave Tubes and Circuits

Microwave Tubes and Circuits:

Cavity Magnetron Working : The Cavity Magnetron Working, which will be referred to as the magnetron, is a diode, usually of cylindrical construction. It employs a radial electric field, an axial magnetic field and an anode structure with permanent cavities. As shown in Figure 11-10, the cylindrical …


Crossed Field Amplifier : The Crossed Field Amplifier is a microwave power amplifier based on the magnetron and looking very much like it. It is a cross between the TWT and the magnetron in its operation. It uses an essentially magnetron structure to provide an interaction between …


Multicavity Klystron : The design of the multicavity klystron, together with all the remaining tubes described here, relies on the fact that transit time will sooner or later terminate the usefulness of any orthodox tube. They therefore use the transit time, instead of fighting it. The Multicavity …


Planar Triode Construction : Planar Triode Construction – A short transit time is essential if grid loss and noise are to be minimized, as is the reduction of internal capacitances and inductances. Also, since coaxial resonant lines and cavities are used as tuned circuits at these frequencies, …


Reflex Klystron Oscillator : It is possible to produce oscillations in a klystron device which has only one cavity, through which electrons pass twice. This is the Reflex Klystron Oscillator, which will now be described. The Reflex Klystron Oscillator is a low-power, low-efficiency microwave oscillator, illustrated schematically in …


Traveling Wave Tube Working : Like the multicavity klystron, the Traveling Wave Tube Working is a linear-beam tube used as a microwave amplifier. Unlike the klystron, however, it is a device in which the interaction between the beam and the RF field is continuous. The TWT was …


Triode Equivalent Circuit : Triode Equivalent Circuit – As frequency is raised, vacuum tubes suffer from two general kinds of problems. The first is concerned with interelectrode capacitances and inductances, and the second is caused by the finite time that electrons take to travel from one electrode …


Types of Magnetron : The Various Types of Magnetron are 20-kW Conventional Metal Ceramic Magnetron 5-MW Long Anode Coaxial Magnetron Frequency agile or Dither tuned Magnetron Voltage Tunable Magnetron The Magnetron, perhaps more than any other microwave tube, lends itself to a variety of types, designs and arrangements. Magnetrons using hole-­and-slot, vane …


Types of Travelling Wave Tubes : The TWT is the most versatile and most frequently used microwave tube. Four Types of Travelling Wave Tubes, each with particular applications and performance requirements. These are now described. TWT Types: The most fruitful method of categorizing traveling-wave tubes seems to be according …