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Secret Knock Detecting Lock

  1. Nov 8, 2009 #1
    How great would this be for a club house :tongue2:

    https://www.youtube.com/watch?v=zE5PGeh2K9k
     
  2. jcsd
  3. Nov 8, 2009 #2

    Danger

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    As a former professional locksmith, I think that the base technology is very cool. From a security standpoint, however, it is far too susceptible to spy-hacking. Once someone realizes that the lock is sonically activated, it will never be secure after one use. Having to change the code every time that it's opened sort of defeats the purpose of convenience.
     
  4. Nov 8, 2009 #3

    turbo

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    Neat!
     
  5. Nov 8, 2009 #4

    turbo

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    When I was in college around 1970, the school required people to follow procedures during vacations. One thing that campus security would do (I knew people on staff) is to select students' rooms and toss them, since they had master keys for every floor of every dorm. I made a neat work-around. I bent a coat-hanger so that it would fit around the inside of the door-knob, and had a narrow V of wire that pressed against the locking button. From that apparatus, I hung a long piece of nylon string and laid it on the floor inside the room. There was no way that you could use a key to open that lock, due to the pressure from the coat-hanger on the button. To open the door, you'd have to twist a couple of open coat-hangars together, slide that long contraption under the door, fish out the string, and pull on the string to pop the coat-hanger off the knob on the inside. Then the key would turn easily. Room didn't get tossed, nothing turned up "missing" with no recourse.
     
  6. Nov 8, 2009 #5

    Danger

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    That is one of the sneakiest, most appealing things that I've ever heard of, Turbo. Hats off to you.
     
  7. Nov 8, 2009 #6

    turbo

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    Thanks. Everything I owned was in that room, and I didn't want to get robbed, especially in an inside job. I financed a lot of my college expenses by buying and selling guitars, amplifiers, etc, and I couldn't afford to lose my stock to some creep with a master key and no ethics.
     
  8. Nov 8, 2009 #7

    Danger

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    You might then appreciate the first security system that I came up with, way back in the near-Detroit days before I ever thought of becoming a locksmith. I don't want to go into details due to the nature of this forum, but leave it suffice to be said that it involved a steel-wool welcome mat, a brass doorknob, and an 280 A arc welder. :biggrin:
     
  9. Nov 8, 2009 #8

    turbo

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    Eek!
     
  10. Nov 9, 2009 #9
    it also had a built in siren that sounded suspicously like some one screaming bloody murder. and probably smelled and sounded like bacon frying
    jezzz, it hurts just thinking about that

    dr
     
  11. Nov 9, 2009 #10

    Danger

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    Yeah... it doubled quite well as a doorbell...
     
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