How does a magnetron produce heat?

The microwave oven uses a magnetron to generate microwave energy. The microwave energy travels through a waveguide and is distributed into a metal cavity where the food is cooked. The waves are absorbed by the food and excite water molecules in the food. This heat then transfers throughout the food cooking it.

What is magnetron and its principle?

Magnetron is a grouping of a simple diode vacuum tube together with built in cavity resonators and an exceptionally powerful magnet. There are three types of magnetrons: Negative resistance type. Cyclotron frequency type. Travelling wave or Cavity type.

What is magnetron in microwave engineering?

Advertisements. Unlike the tubes discussed so far, Magnetrons are the cross-field tubes in which the electric and magnetic fields cross, i.e. run perpendicular to each other.

What is a magnetron do?

Magnetrons are capable of generating extremely high frequencies and also short bursts of very high power. They are an important source of power in radar systems and in microwave ovens.

What voltage does a magnetron use?

Operation of Magnetrons This supply can provide an AC or DC voltage, with typical voltages ranging from 2.5 V to 15 V, and currents ranging from a few A to 100 A and above. The filament voltage has to be applied some time before the cathode voltage so the filament has sufficient time to pre-heat.

What is the frequency range of magnetron?

A: A magnetron is a specialized vacuum tube which does one thing: it is a power oscillator source for frequencies of several hundred MHz to several GHz. Depending on size and other factors, it can produce tens and hundreds of watts to kilowatts.

Who invented magnetron?

A type of electron tube called a “magnetron” had been invented almost twenty years earlier by U.S researcher A. W. Hull. Hull’s tube had a hot filament wire that emitted and a cylindrical plate around the filament that collected them.

Is a magnetron AC or DC?

The magnetron requires DC to operate, not AC. DC current remains constant over time, maintaining a consistent positive value as shown in Figure 2. It is this type of consistency that the magnetron needs to operate.

How efficient are magnetrons?

Within these loose constraints, magnetrons have proven to be highly efficient and compact sources, often achieving efficiencies as high as 70% or more. Additionally, the conventional magnetron, among all vacuum devices, is exceedingly simple in design and construction, making it a cheap source of microwave power.

What is the difference between magnetron and klystron?

The magnetron used only as an oscillator. In a klystron, the electron is injected normally from the cathode. But in the case of magnetron, the electrons are forcefully injected. In a klystron, the electrons move linearly in the tube and in the magnetron, the electrons follow a spiral path from cathode to anode.