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New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

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EMF detection using a multimeter

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    EMF detection using a multimeter

    Does anyone know where I can find the circuit for a emf detector using a multimeter?? I have tons of parts, and I wanna use some of them. I also have a multimeter. I know there is some kind of probe to be made from bits and pieces, and I have lots of those, too. Any help???


    Nathan
    The ancients knew *more* than us...
    http://www.legendarytimes.com/forum/index.php They're baaaack!

    Come and see http://www.gamegavel.com for all your gaming needs! We have Zero-ohm resistors!

    #2
    Which definition of EMF are you referring to, electro-motive force, or electro-magnetic force (or field)? electro-motive force, IIRC, is just an old obsolete term for voltage, which the multimeter already has the capability to measure. Therefore, I'm assuming you're trying to measure electro-magnetic force, right? Try this one:

    http://www.mitedu.freeserve.co.uk/Ci...ar/emmeter.htm

    --T
    Teach your children how to think, not what, and hold 'em close, not tight.
    _____________________________________________

    Please visit the Vintage-Computer Wiki. Contributers welcome.

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      #3
      Yes, electromagnetic force. Kinda tired to build anything at the moment but the circuit diagram or plans would be helpful after I get some shut-eye.
      The ancients knew *more* than us...
      http://www.legendarytimes.com/forum/index.php They're baaaack!

      Come and see http://www.gamegavel.com for all your gaming needs! We have Zero-ohm resistors!

      Comment


        #4
        The disign on that web page says it is limited to only about 100KHz. That is pretty low frequency response. Do have any specific sensitivity frequency requirements? A multimeter can be pressed into RF sensing by putting a 0.01 to 0.001 mFd capacitor across the terminals, connecting one terminal to one end of a germaniun diode (1N34A is a good one) and connecting the other end of the diode to a short length of wire. The wire acts as a pickup and the meter will read like a field strength meter.
        --Wayne

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          #5
          No specific requirements. Just as wide a range as I can get. I had the thing described to me a while back, and I had in mind a kind of coiled antenna setup on a long pole. Guess the person waa thinking about something different. Just free enough to post this, no time as yet to scrounge through parts I have to put this(these) together yet. I was actually thinking of a large rig that canbe mounted on top of a car, but I guess it isn't necessary. I love this stuff.
          The ancients knew *more* than us...
          http://www.legendarytimes.com/forum/index.php They're baaaack!

          Come and see http://www.gamegavel.com for all your gaming needs! We have Zero-ohm resistors!

          Comment


            #6
            I'm still here, but my phone lin eat home got cut off cause of a large bill. I should be back up and communicatin' this week though. I was thinking of getting cable and making everything in the house communicate, but whatever. I'll be back online soon. I wanted to drop a note here from the public library computer and let everyone know whom I have been talking to that I didn't disappear, just lost my line for a little while.

            Nathan
            The ancients knew *more* than us...
            http://www.legendarytimes.com/forum/index.php They're baaaack!

            Come and see http://www.gamegavel.com for all your gaming needs! We have Zero-ohm resistors!

            Comment

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