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Creating a telegraph, quick question?

  1. Jan 16, 2012 #1
    Could someone tell me the fault in my design?

    Here is how I set it up:

    I am using 22 gauge hookup wire, all of the metal is steel (magnetic), and the nail in the electromagnet part is iron.

    Am I connecting the wires to the wrong metal parts, or doing so incorrectly? I found this set up at: http://w1tp.com/perbuild.htm

    Please help, I am so lost :(
  2. jcsd
  3. Jan 16, 2012 #2


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    The electromagnet should be farther out towards the end of the metal strip. Also, you should have the nail installed that prevents the metal strip from going up too high away from the electromagnet. The nail I refer to is the one that makes the 'clack' as described in your link. When you press the key is the electromagnet working? Is it magnetic at all?
  4. Jan 16, 2012 #3
    Yes further out toward the end and much closer to the nail. Maybe 1/16th of an inch or less.
  5. Feb 23, 2012 #4


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    You may have a lot of rather high resistance electrical connections also, such that you are unable to draw much current through your magnet. If you could solder all of your wire-to-nail and nail-to-metal strip connections, you might see significantly better performance.

    The previous comments about reducing the air gap over the magnet and placing the air gap closer to the end of the armature are extremely important as well.
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