Ultrasonics refers to signals that are above the human hearing span (>20 kHz), and usually in the 40- to 70-kHz range. These signals are used like radar—they’re radiated toward a target and reflected ...

Zac has been writing about Android as a hobby since he was a teenager and fulfilled his ambition of doing so professionally when he joined Android Police as a Reviewer in 2020. Zac specializes in ...