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Can we get Higher Frequencies from an Oven Magnetron?

  1. Mar 3, 2017 #1
    magnetron.gif
    Is it possible, and if so, how should we modify a typical oven magnetron so as to produce higher frequencies of EM radiation?
     
  2. jcsd
  3. Mar 3, 2017 #2

    davenn

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    no, they are designed to oscillate at a specific frequency

    and what dangerous things were you planning to do with 100's of Watts of microwave power ?


    Dave
     
  4. Mar 3, 2017 #3
    I know, but with modifications?

    change the frequency so as to resonate with the other components of food, besides the water in food.
     
  5. Mar 4, 2017 #4
    I guess you could decrease the Brownian motion by freezing it with liquid nitrogen and thus increase the photon energy aka frequency. It works with lasers and leds, I doubt it will with a magnetron, though.
     
  6. Mar 4, 2017 #5

    Baluncore

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    https://en.wikipedia.org/wiki/Microwave_oven#Principles
    https://en.wikipedia.org/wiki/Microwave_oven#Design
     
  7. Mar 4, 2017 #6
  8. Mar 4, 2017 #7

    Baluncore

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    What specifics ?
    The legal restriction on frequency is decided by licensing of radiation sources.

    Wavelength is set by the dimensions of the resonant cavity, if you make it bigger it will have a proportionally longer wavelength = lower frequency. Every time a magnetron is turned on it heats up and physically expands, so the frequency chirps slightly downwards in the ISM band.

    Magnetic field is unimportant as it simply sets the direction of curvature of the electron paths. Variation of field can give maybe a one percent change in frequency, but extreme changes will lead to higher internal losses and cooling problems.

    Internal “Pi strapping” effectively short circuits all modes, (except for the most efficient), by forcing the phase between cavities to be Pi radians = 180°. Only a small proportion of the circulating internal resonant energy is extracted per cycle so the frequency cannot be pulled by changing the external tuning to select another mode or harmonic at a different frequency.
     
  9. Mar 5, 2017 #8
    A microwave oven does not operate at a resonant frequency of water. Any frequency will do.
     
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