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Modulating a dc current

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Wagaloo, Mar 7, 2018.

  1. Wagaloo

    Wagaloo New Member

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    Hi, i am learning electronic, and i can't figure that one out.

    I know that "when a fluctuating electric current flow through a wire, it generates a magnetic field", is the reverse true. Can you use a magnetic field to modulate an electric current. If it's the case, can i use this in a circuit with a constant load like a class A amplifier?

    I'll appreciate if you could help, thanks.
     
  2. crutschow

    crutschow Well-Known Member Most Helpful Member

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    Yes, that's how transformers work.
    But to do it in a single wire generally requires a large magnetic field for even just a small voltage deviation (the current deviation from this voltage depends upon the resistance of the wire and its load).
     
  3. dknguyen

    dknguyen Well-Known Member

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    It's also how generators work. They use a steam power (or a gas engine) to turn a giant rotor with magnets on it and the magnets move past coils of wire which produces current in the wire.
     
  4. dave miyares

    Dave New Member

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  5. crutschow

    crutschow Well-Known Member Most Helpful Member

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    Technically it produces voltage.
    The current depends upon the impedance (load) of the wire.
    Thus a generator with no load still produces voltage, but no current.
     
  6. dknguyen

    dknguyen Well-Known Member

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    Yeah, but I chose to say current so as not to confuse the OP since that's the way he phrased it and there seems to be a language barrier.
     
  7. crutschow

    crutschow Well-Known Member Most Helpful Member

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    Okay.
    But I think it's better to be technically correct than to be concerned about a possible language barrier or confusing the OP. ;)
    If the OP doesn't learn the correct terms, then he will continue to perpetrate his incorrect understanding.
     
    • Informative Informative x 1
  8. dave miyares

    Dave New Member

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  9. dknguyen

    dknguyen Well-Known Member

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    My leniency varies from day to day depending on how charitable I'm feeling
     
    Last edited: Mar 7, 2018
  10. alec_t

    alec_t Well-Known Member Most Helpful Member

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    Magnetic tape heads and dynamic microphones are other examples where a changing magnetic field produces electrical changes.
     

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