Anonymous asked in Science & MathematicsEngineering · 1 decade ago

Getting voltage by manually turning the dc motor.?

I notice that on some simple dc motors used for dvd players, rc cars, audio cassette players, turning the rotating thing manually produces enough voltage (depending on how fast I turn it) on the battery input wires to light up a led (3 to 5v)while some of them don't even produce .10 v. Why the difference? Does it have to do with how thick the magnets are or the coil winding? Is there a universal way to distinguish between the two?

4 Answers

  • Anonymous
    1 decade ago
    Favorite Answer

    DC Motor speed control circuit

    United States Patent 4093901


    A DC motor speed control circuit in which the current to the motor is delivered in a series of pulses the width of which is variable in accordance with the setting on a throttle control potentiometer. The pulses are shaped to provide a fast turn on and slow turn off of the control transistor to avoid heat build up and lessen the inductive kickback of the motor. A novel feedback circuit senses excessive current draw and automatically shuts down the circuit and remains latched in that condition until the throttle control potentiometer is reduced to zero whereupon the circuit automatically resets itself. High efficiency is achieved by directing both the power current and the control current through the motor windings thus increasing the battery life.

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  • 1 decade ago

    Here are the sad tales of two people who ran into the same problem.

    One was told by Nintendo Careline they had to bring it to a service center (for on the spot service)

    This other one gets the advice that there *is* a paperclip-hole, but that it is behind the front panel plastic, which you would need to remove. I don't know if removing cosmetic aspects like that voids your warranty in your area. At your own risk :)

    I have the same player and I use either Windows Media player 11 or Yahoo Musicmatch Plus (cost of this is $19). I either upload a CD then transfer to Sandisk or I download songs from the web using MP3 Rocket 5.01. I paid for that some time ago but I THINK it might be free now, not sure about that.

    I am not real computer savy so if I can do it anyone can. Good Luck

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  • 1 decade ago

    If a motor has permanent magnets, it can produce voltage by spinning it with bare wires. If a motor gets its magnetism from coils of wire then the only voltage you will get out of it by spinning it is a slight result of residual magnetism. There is also a possibility that one would have a built in diode so it only turns in one direction even if connected with reverse polarity (unlikely.)

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  • 4 years ago

    if gas is there and a spark that is going to commence, could no longer run nicely in spite of if that is going to consistently commence. I presume you realize there's a spark on the plugs for the reason which you have taken the plug out, rested it on the block and seen a spark as you crank the motor? if the spark replaced into fat then that is going to be wonderful, attempt cleansing the physique of the plug in case the spark is going to floor in the previous it meets the gas? i assume you realize gas is there for the reason which you are able to scent it from plug hollow, terrific

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