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how to make a circiut that senses and responds to megnetic fields? Answered

I need to make a circuit to power an overunity generater

6 Replies

normj (author)2011-11-04

Here are a couple of links that give good examples of how to manufacture a gauss-probe.


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Jack A LopezBest Answer (author)2011-11-04

There are a couple of tricks for detecting magnetic field. The two I have seen most often are pick-up coils, and Hall effect sensors.

A pick-up coil gives you voltage proportional to the time-rate change of the magnetic flux through the coil, and proportional to the number of turns, and this is just Faraday's law of induction.
Note this kind of sensor requires a magnetic field that is changing, and gives a response proportional to this time-rate of change.

If you want a sensor that responds to magnetic field directly, and that will also work with DC magnetic fields, then you want a Hall effect Sensor.

There are a couple of different kinds of Hall effect sensor.  If you want a response that's proportional to magnetic field strength, then they call this kind a linear hall effect sensor. 

There are other kinds of Hall effect sensor that just sort of switch on (or off) depending on the magnitude of the field they're detecting.  These switchy kind of Hall effect sensors get used a lot in position sensors in brushless motors; i.e. a magnet moves by the sensor, and then the sensor switches, and this tells the controller the position of the rotor.

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seandogue (author)2011-11-04

Several loops of wire, connected through a resistor, will sense a magnetic field.

Basically, it's using a solenoid in reverse, and it's the basis for metal detectors, among other uses (like current sensors...)

As a sensor, fine gauge wire can be used to increase the sensitivity with minimal size. The larger in diameter you make the loop(s), the more sensitive it will be. The more loops you use the more sensitive it will be.

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seandogue (author)seandogue2011-11-04

(measure the voltage across the resistor to detect the field).

It can get more complex depending on what you want to do, (for instance, in commercial metal detectors, the system is active rather than passive as in my example and more complicated than I care to outline right now) but that's the basics.

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lemonie (author)2011-11-04

Far too vague.
Have you tried praying or sacrifices?


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kelseymh (author)2011-11-04

You could do just about anything you want for your "overunity generater" [sic]. Just make sure you include a carefully hidden battery so people will believe it actually works.

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