Schematic for creating a modulated electrostatic field (300 Vpp, 50mA)

Discussion in 'The Projects Forum' started by Southrend, Apr 12, 2016.

  1. Southrend

    Thread Starter New Member

    Dec 28, 2015
    Hi all,

    I've seen a device that can create a modulated electrostatic field to transport sound through a human body. More details about this device can be found here:

    The following is en exerpt from the text:
    This amplification driver converts the sound loop into a high voltage, low current (~300 Vpp, ~50 mA) inaudible signal which is applied to the conductive metallic casing of the microphone via an additional connector. When holding the microphone, the visitor comes in contact with the inaudible, high voltage, low power version of the recorded sound. This creates a modulated electrostatic field around the person’s body. When touching and sliding hand on an object such this modulated electrostatic field creates a very small vibrations. As a result, both the finger and the object together form a speaker, that makes the signal audible.
    I want to create a similar device to deliver a very import message to my relatives in a way that will blow them away (both message and delivery ;)). However I'm at a total loss on how to build this thing.

    The only thing I know is I need a power source, a sound source (I will go with a prerecorded sound), an amplifier and basicly a wire connected to my skin. Could anyone of you help me with this project?

    For one thing, I'm kinda scared of touching wires with 300V on them.
  2. OBW0549

    Distinguished Member

    Mar 2, 2015
    Don't do this. Just don't. The only message it will send to your relatives, at your funeral, is "don't play around with high voltage."
  3. Southrend

    Thread Starter New Member

    Dec 28, 2015
    You see, that is exactly the same thing I was worried about. I guess I should listen to my instinct and the expert
  4. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    I suspect that the current is a misprint.

    I could see this working if the current was in the MICROAMP range instead of the 1000 fold higher milli amp range.
  5. Alec_t

    AAC Fanatic!

    Sep 17, 2013
    :eek: It probably will!! A current of 50mA through the human body can be LETHAL.
    Don't trust everything written by journalists!
  6. bertus


    Apr 5, 2008

    50 mA will be lethal:


    This image is taken from the factsheet book I posted.
    Here is the complete book: fakta55.pdf

  7. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    There is more going on with this tech. Much more than a low current high voltage audio signal.
    The effect, it is stated, "creates a speaker".
    The signal is probably a much higher freq that is modulated by an audio waveform. My guess would be something around 80 to 100 kilohertz, like the old bose amplifiers used, with an audio signal modulating the sinewave. Exactly like AM radio but at a lower frequency.