Difference between magnetron and TWT

Discussion in 'General Electronics Chat' started by electronewb, Aug 19, 2012.

  1. electronewb

    Thread Starter Member

    Apr 24, 2012
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    I've been watching a bunch of videos on MOT and came across on the different ways of producing RF energy which led me to RF and radar system and RF transmission. What are the main differences between the 2 in regards to RF transmission?
     
  2. #12

    Expert

    Nov 30, 2010
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  3. electronewb

    Thread Starter Member

    Apr 24, 2012
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    So what amplifies the signal in a microwave oven?
     
  4. maanga

    New Member

    Aug 20, 2012
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    Magnetron is a high voltage diode (vacuum tube) with strong magnets attached to sides. As the electrons flow, the flow is bent on the sides because of the magnets. The electrons at the center flow straight. This causes a delay in the bent electrons reaching the anode. Delayed bombarding causes microwave to be generated.
    regards,
    Maanga
     
  5. #12

    Expert

    Nov 30, 2010
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    What amplifies the current in a flashlight? Nothing. The inherent properties of the parts are sufficient. When you build a magnetron oscillator that uses 1000 watts, it doesn't need an amplifier.
     
  6. electronewb

    Thread Starter Member

    Apr 24, 2012
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    So would it be possible to use a magnetron to transmit an audio and video signal?
     
  7. #12

    Expert

    Nov 30, 2010
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    Theoretically, yes. Problem is, I have never worked anywhere near that frequency. For all I know, they use magnetrons in communication satellites. (That's supposed to be funny.)

    But seriously, transmitting information means modulating the carrier wave, and modulating a kilowatt carrier isn't the best method. Modulate first, make kilowatts second.

    Anybody else know the answers?
     
  8. JMW

    Member

    Nov 21, 2011
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    It's difficult to modulate a maggie. Unless you consider pulsing it like a RADAR, using either a Morse or ASCII type of format on off or long pulse short pulse length as the mark space dictates. I would recommend a Klystron for AM/FM etc. At this point there are 21st century solutions, but the above served well in the 20th, if the parts are still available.
     
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