411 posted 3 years ago by UncleHooly 3 years ago by UncleHooly +411 / -0 143 comments share 143 comments share save hide report block hide replies
IIRC it was just a harmonic resonator, that vibrated the support pillar it was attached to at the right frequency. Think people walking in lockstep on a swingbridge
You could always try lockwire.
https://www.youtube.com/watch?v=OwFjUX6SaY8