Humanbody- deadbody: electricity?

Discussion in 'General Electronics Chat' started by onlyvinod56, Dec 26, 2013.

  1. onlyvinod56

    Thread Starter Senior Member

    Oct 14, 2008

    When an oscilloscope probe terminal is touched with hand, some kind of disturbance signal is observed.

    an audio amplifier (tested with TBA810) is powered and a small speaker is connected. When its input terminal is touched with hand a large hissing noise is produced.

    What does these indicate? What can you explain the human body in this context?

    If these things are repeated with a dead body do we get the same results?
  2. MrChips


    Oct 2, 2009
    We are surrounded with EMI, electromagnetic interference.
    What you observe on the scope or hear on an audio amplifier is this EMI, particularly AC line frequency and its harmonics.
    A human body alive or dead acts as a pickup antenna.
  3. strantor

    AAC Fanatic!

    Oct 3, 2010
    The human body does generate its own electrical signals. If your probes are in the right spot, you can read them. Google EMG signals. But if you aren't deliberately looking for those signals then you're probably experiencing EMI as mrchips said.
  4. ian field

    AAC Fanatic!

    Oct 27, 2012
    If the dead body is laying on a grounded stainless steel autopsy table - probably not.