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Electromagnet

Discussion in 'Electronics & Electrics' started by ][nfector, Nov 3, 2005.

  1. ][nfector

    ][nfector Member

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    im looking to build an electromagnet powerful enough to corrupt/erase the contents of a vhs tape (at very close proximity) so it's screwed enough not to play back properly. The problem is that it can only be powered of a 12 volts car battery and i don't have much of an idea about constructing electro-magnets other then wat i learnt in physics :(
     
    Last edited: Nov 3, 2005
  2. NoOzL

    NoOzL (Banned or Deleted)

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    if u wanna destroy it hammer does wonders :)
     
  3. OP
    OP
    ][nfector

    ][nfector Member

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    nah its more of a self destruct mechanism.
     
  4. OCMunkee

    OCMunkee Member

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    So his homemade porn videos can be erased quickly when his girlfriend tries to take them... :lol:
    --Nathan
     
  5. orbitaudio

    orbitaudio Member

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    just wrap some insulated wire around a metal rod. The more winds the, stronger the magnet.

    i wouldn't use a car battery though, caus you may draw too much current, and the wire will heat up too much. depends on the resistance of the coil, which depends on wire thickness + amount of turns.
     
  6. OCMunkee

    OCMunkee Member

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    Agreed, a car battery would probably melt the wire. Not a safe thing to do. I didn't really think about that one when I made my silly post. :p
    --Nathan
     
  7. dazzawul

    dazzawul Member

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    Set up the coil on a ferrous bar (Iron or steel rod, whatever) and wire an inverter up to the coil, run it off of a couple of 9 volt batteries in parallel so that it lasts a little longer.
    This'll make an oscillating magnetic field which would be great for wiping out any magnetic fields, and also as a degaussing wand :p.

    cheers lads.
     
  8. OP
    OP
    ][nfector

    ][nfector Member

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    so u mean wire an inverter to step up the voltage and then it would presumably be AC hence oscillating magnetic field?

    do u think having the electromagnet within the vcr (right near the tape but as far away as possible from the read/write heads, would cause damage to the VCR itself? I dont plan on operating the electromagnet whilst the VCR is on though.
     
  9. hlokk

    hlokk Member

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    re-edit: remembered what i was talking about. DC current means you will get a single direction magnetic field. AC will cause changing magnetic field which should stuff the tape up nicely.

    Why dont you either rip the tape out and burn it or use a neodymium or some other rare earth magnet?
     
    Last edited: Nov 4, 2005
  10. thydzik

    thydzik Member

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    what about just using those strong magnets found in hdd, a old hdd can be obtained for free
     
  11. OP
    OP
    ][nfector

    ][nfector Member

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    strong magnets IN hardrives??? are they electromagnets or just magnetic metal? :eek:
     
    Last edited: Nov 4, 2005
  12. OP
    OP
    ][nfector

    ][nfector Member

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    Because it's somewhat of an automatic self destruct mechanism. You seem to be missing the point a bit :)
     
  13. Goth

    Goth Grumpy Member

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    Neodymium-Iron-Boron permanant magnets. Very strong, and yes, they're IN the hard drive. And yet they dont affect it. Because the magnetic field is static as far as the discs are concerned.
     
  14. JaC

    JaC Member

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    Is there a specific need for electromagnetism? Could the job be accomplished with fire? Fire is good, y'know.....
     
  15. nux

    nux Member

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    Seems like he wants some sort of auto-destroy feature to delete his kiddy-porn when the cops show up.
     
  16. hlokk

    hlokk Member

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    I cant miss the point if you didnt ever say it.

    explain fully what you want to do.


    Sounds like u have some porn stash that you want erased if anyone finds it :lol: but then why wouldnt your porn be on the computer :p
     
  17. DeNs

    DeNs Member

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    Hah, the least likely thing I would have expected someone else to suggest has been suggested :p

    My friend really likes getting the magnets out of all the old dead drives i've got lying around at home. They're damn strong i'll tell ya. Dunno if they'd suit this situation, but you never know until you try!

    ---dens
     
  18. Captain-Nasty

    Captain-Nasty Member

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    ROFL all you guys are blind!

    Ok what he is saying (from what I can tell) is he wants to kill a VHS tape in a VCR that he has with an electromagnet if anyone tries to take it out without him knowing.

    Lol 2:1 I bet that he is trying to make homeporn with his girlfriend :lol:

    You bloody legend :thumbup:
     
  19. LethalCorpse

    LethalCorpse Member

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    If you want to totally bork the tape, as in completely non-recoverable, you're going to have a hard job of it. Magnetic field strength drops away with the cube of distance - ie, if it's more than a few mill away from the tape, you're not going to be able to totally destroy it. That's unless you produce the sorts of magnetic field found in an MRI machine, ie buckets of power. You could do it with a basic electromagnet, but you'd need to get the entire tape within the effective range of the field, so unless you're bending spacetime you'd need to run the entire tape from reel to reel past the electromagnet at short range. Dunno about your VCR, but in most I've seen the feds will have popped your tape by the time the first cheerleader is on her knees. A much more effective solution would be a small quantity of plastique explosive inserted into the tape, and an appropriate detonator solution. It'll neatly destroy any object in an easily defined radius - I believe there are lookup tables. And it won't require you to run 4gauge cable through your VCR.
     
  20. hlokk

    hlokk Member

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    He didnt even mention VCR, he just said that he wanted to destroy the contents of the tape, then later he told us he wanted to do it automatically
     

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