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Anyone for project ideas for microwave? and maybe some help while you're at it

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Mishael, Feb 27, 2010.

  1. Mishael

    Mishael Member

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    I just took apart a microwave and i would love to just build something(s) out of the sweet-looking parts i just got. i have a magnetron, an AC/AC transformer, capacitor the size of my fist, a 6 RPM 21 VAC motor, and a fan id say that is about 5-6 inches. any ideas?

    also, i took this apart and i found a transformer as i said. its huge and heavy and coated in polyurethane. how can i tell its output voltage? that capacitor i was talking about earlier i need some help with too. i read it, and it was saying its only .8 µF but something like 2100WVAC. is that watts? or just a model number. it also says no PCB i guess for obvious reasons.

    on a final note, can anyone explain to me how a microwave works? i mean, i know i could just go to wikipedia or something, but here i can ask questions. i know what it does to food but how does the magnetron works, how does capacitor fit in and why doesnt the metal enclosure catch fire when the magnetron is powered (im assuming a charge of sorts)?
     
  2. MikeMl

    MikeMl Well-Known Member Most Helpful Member

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    The transformer will kill you. The magnetron will blind you. Use it only as a paperweight.
     
  3. Dick Cappels

    Dick Cappels Member

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    I echo MikeMl's warning: That transformer is very dangerous, even for those who are experienced in working with high voltage. It is capacble of high voltage and high current at the same time. Deadly.

    it would make an excellent doorstop.

    You can make a stand, frame, and enclousre for the fan and with the appropriate precautions, use it as a desk fan.

    The six RPM motor can (probably) be powered from a doorbell transformer and used to turn a turntable holding some sort of display.

    Please don't hook the transformer to anything. If you can take it apart without hurting yourself, it would be a valuable source of magnet wire.

    Here is a web page with more ideas:

    Salvage Parts and Sources - Open Circuits
     
  4. dave

    Dave New Member

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  5. Hero999

    Hero999 Banned

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    The motor is probably used to turn the plate of food.

    In my experience the motor tends to be rated at the mains voltage, are you sure it's 21VAC?

    The motor is normally synchronous permanent magnet type which means it can be used as a generator, if you turn the shaft and hold the wires it will give you a shock. There was a project on the Internet which showed you how to use the motor to power a small wall wart to charge a battery or power a small appliance but I'm doubtful you'll get that much power unless you turn the sharf really fast.
     
  6. Mishael

    Mishael Member

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    MikeML: There was a reason i wanted to ask before i did anything. The trasformer is very heavy, the magnetron is too light but bulky. I dont think i will be weighting papers with those anytime soon.
    Dick Capples: the transformer is coated in polyurethane and welded. I dont think i will ever get it apart. Id say it weighs a good 10-15 pounds. I like the turntable idea though.
    Hero999: yes it is 21 because it screams it at you on the bottom of it. Unfortunately the motor spins much faster than around 6 RPM but i took it apart and its got something like a 1000:1 gear reduction

    Can anyone help with the capacitor or the transformer's output voltage?
     
  7. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I repair microwave ovens, I've never seen one that didn't use a mains turntable motor - and I see a lot of the motors, because people strip the gearboxes in them :D

    The halfwave rectified output from the transformer is about 3000V at a considerable current - it's pretty well guaranteed to kill you. Don't mess with it! - it's the most dangerous home electrical item there is.
     
  8. Hero999

    Hero999 Banned

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    Try turning the shaft and measuring the voltage produced, unless it's an induction motor, you'll measure a voltage near that of the voltage supplied to it.

    That's normal, the actual motor normally rotates at the mains frequency 50Hz = 3000rpm in the EU, 60Hz = 3600rpm in the US.
     

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