Hi Zach, Thank you for the feedback, Im glad the blog inspires
experimentation. The PIP conversion should work for any permanently polarised
condenser, i.e an electret based mic. The spider in the bag is actually on
topic. I watched a show where they were trying to record insects with some
hydrophones but failed to consider the mass of the glass sheet vs the dynamics
of the movement. Optical is far better e.g with a small laser vibrometer "spy
scope" its possible to listen to the sound of pollen grains tumbling in a rain
drop. Small sighting telescope, laser behind the main objective, photodiodes
(pip powered) behind the eyepiece, line them up reflecting from the surface of
interest. simply shine it to mylar and capture the amplitude modulated (the
sheet) reflection. Range is limited to about 6" due to the main objective. Its
possible to bring the device in close to form a bright spot and analyse the
roughness of dust, pollen, feathers etc by moving the laser over them quickly.
BR
Mike.
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