Havana Syndrome.tech

No single ultrasonic tone would do this, but as with musical combination tones, combining more than one can create audible byproduct sounds, including by accident.

3/1/2018 Electrical engineering and computer science professors Wenyuan Xu from Zhejiang University and Kevin Fu from the University of Michigan explain their research, which suggests a more likely scenario of sloppy engineering, and what ultrasound frequencies (which can be used to transmit information gathered by listening devices) traveling through the air can – and…