Operation of Magnetron
The magnetic fields of the moving electrons interact with the strong field supplied by the magnet. The result is that the path for the electron flow from the cathode is not directly to the anode, but instead is curved. By properly adjusting the anode voltage and the strength of the magnetic field, the electrons can be made to bend such that they rarely reach the anode and cause current flow. The path becomes circular loops. Eventually , the electrons do reach the anode and cause current flow. By adjusting the dc anode voltage and the strength of the magnetic field, the electron path is made circular. In making their circular passes in the interaction chamber, electrons excite the resonant cavities into oscillation. A magnetron, therefore, is an oscillator, not an amplifier. A takeoff loop in one cavity provides the output.
Magnetros are capable if developing extremely high levels of microwave power. Thousand and even millions of watts of power can be produced by a magnetron. When operated in a pulse modo, magnetron can generate several megawatts of power in the microwave region. Pulsed magnetron are commonly used in radar systems. Continuous-wave magnetrons are also used and can generate hundreds and even thousands of watts of power. A typical application for a continuous magnetron is for heating purposes in microwave ovens.