Metal detector made from a radio and calculator.


Let me explain: when working, the calculator emits its own radio carrier frequency. Our task is to catch it with an AM radio. And with the CD box we adjust the signal level - making it barely audible, so that when a metal object is brought in, the generation frequency of the calculator changes or is weakened.


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Comments (4)
  1. purgen2013
    #1 purgen2013 Guests 25 November 2011 19:59
    1
    I'll take note!
  2. qwert
    #2 qwert Guests 11 September 2013 13:25
    2
    It won't work.The calculator frequency is stabilized by a quartz resonator.
    1. BENDER39
      #3 BENDER39 Guests 25 April 2018 07:19
      2
      The frequency of the oscillator does not change, it’s just that when you bring the calculator to the piece of hardware, the receiver wheezes louder, because the piece of hardware works like an antenna. Here’s a canoe
  3. Vasya
    #4 Vasya Guests 16 February 2016 20:52
    1
    Yeah, he can smell a coin 10 cm away, but the ring isn’t even close to his finger?