http://www.theregister.co.uk/2017/08/16/engineers_show_how_to_construct_mak= eshift_acoustic_levitator/ Make an acoustic levitation chamber. I haven't checked out the referenced p= aper yet, but according to the article it tells you how to do it. --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .