View single post by Jeff
 Posted: Mar 6th, 2008 02:21 PM
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Jeff

 

Joined: Nov 7th, 2007
Location: Alabama USA
Posts: 127
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 Interesting thought Mark.  Here is one way to approach that.  To capture vibrations of non-ferrous material, a transducer is necessary:

Place the hair in a tuning fork arrangement, such that the hair is pulled taught (just short of breakage) across the top of the tines.  I would recommend a fine-threaded vernier for this.  Then there would be two ways to pickup the vibrations:

1.  Simply place a highly sensitive condensor microphone against the fork, and amplify the mic's outputs.  Or,

2.  Glue magnets on the sides of the fork, and wind a coil of fine transformer wire around the magnets to pickup vibrations.  Set the impedance of the coil to match the microphone input of an audio mixer (Hi-Z, > 10k ohms, or Low-Z, <200 ohms).  Build a low-loss cable that will carry the voltages produced to the mixer.  Voila!

Jeff