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R.F. Oscill'motor'

  1. Oct 11, 2012 #1

    PhysicoRaj

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    Gold Member

    Hi,
    Can you turn an electric (DC) motor into a powerful R.F. oscillator? I see that an ordinary motor is already an oscillator which produces noises in the receiver, but One that produces a sharp, distinct, recognizable signal (or noise) (of any frequency) in a receiver? I just don't want to use any electronic components bcuz I can just take to those simple a.m transmitters if I used transistors and condensers.. an 'electrical' method would do.
    Thanks.
     
    Last edited: Oct 11, 2012
  2. jcsd
  3. Oct 11, 2012 #2

    berkeman

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    Staff: Mentor

    No, not really. The electrical noise you hear is from the sparks from the brushes making and breaking contact.
     
  4. Oct 11, 2012 #3

    davenn

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    But on the other hand ... you can use an AC generator to produce a RF signal. This was done in the very early days of radio when there were few transmitters like that around.
    Now days it would be strongly frowned upon without the output of the generator being well filtered to stop harmonics etc that would cause interference noise right across the spectrum upsetting other legit users

    Dave
     
  5. Oct 12, 2012 #4

    PhysicoRaj

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    But it would need some turning to go on with.. so I think of only inductor... some capacitors and resistances( 1 or 2 transistors would do). A simple oscillator that can be modulated by a signal from a microphone.
     
  6. Oct 12, 2012 #5

    davenn

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    the generator itself IS the oscillator. This is the way it was done back in the early days of radio. Nowhere near as stable as today's crystals, VCO's and PLL's etc but it worked :)


    Dave
     
  7. Oct 13, 2012 #6

    PhysicoRaj

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    Thanks..
     
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