+ Submit your article here

What is a Magnetron

11/18/2013 5:08:08 PM | by Anonymous


Magnetrons are basically devices that utilize the interaction of electrons that are guided by the magnetic field. The magnetic fields with cavities within the blocks of copper are to produce microwave radiation. The range of frequency of the radiation is highly dependent on the cavity size. The devices are usually used in radar and microwave ovens. The radiation would cause the molecules in food to vibrate. This leads to the rapid rise in temperature that is sufficient for it to cook the food.


A single magnetron would consist of a short cylinder that is made of copper with several cavities within it. They are left open into the central vacuum chamber containing the metal cathode. The magnet that is permanent provides a field that runs parallel through out the entire axis of the cylinder. The cathode is then heated by the high voltage current. This causes it to produce electrons that streams outwards of the cylinder wall. They are usually at right angles to the magnetic field.


The electrons usually results in being deflected by the filed into the curved paths. This allows them to set up circular currents within the different cavities. These currents would then produce radiation at different frequencies related to the size of the cavities. It is important that the microwaves are directed to wherever that is appropriate. This is done by the metal structure known as the waveguide of which the waves travel. They are normally extended on the outside of the main body from the primary cavity.


This captures the wave signals and guides them along the length. In the case of the magnetron that is used for radar, the waveguide connects to the antenna that is used to transmit the waves. In the case of microwaves, the waves are directed into the chambers of the oven so that they can be used for cooking.


The use of magnetrons is typically to generate microwaves for radar as they progress to achieving the required power output. The only down side is that despite the radar of frequencies produced is determined by the size of the cavities. There are also variations with the range that is caused by the fluctuation of the current and change in temperature.


These days, there are more familiar uses of magnetrons in the microwave ovens. They direct the waves into the small chambers in which the food gets cooked almost immediately. Some molecules in food are also polar. This refers that they have positive charges and negative on either sides. This molecule aligns themselves to the alternating electric and magnetic fields that are produced by the waves. This is due to the bombarding with the electromagnetic radiation that is within the microwave range. This would result in them vibrating extremely fast leading to faster heating. An example of such a case would by the molecule of water.


An employee for a well known company known as Albert Hull, he conducted various researches on vacuum tubes when he first created the magnetron way back in the 1920s. He first thought of the few uses for the invention which mostly stayed unused. Only in the later years, two other engineers joined his venture and explored the device more in depth.


The earlier versions consisted of using mainly a cathode and anode within the internal of the glass tube. However, the two other guys used copper instead. Copper being a good electrical conductor to form the casing of the cavity resulted in the device gaining more power and becoming more powerful. This enabled them to producing the output of 400 watts in the space that was smaller than what was four inches.

Are you sourcing for a product or service?

Do you need a quotation?