Anti-theft tags contain a tiny mechanical oscillator that is activated by a magnetic field. The detectors at a shop's doorway can detect the oscillation magnetically. The tag can be activated and deactivated by magnetizing or demagnetizing it, respectively.
Posted 4 years ago by boyt in category: geeky   Comments (0)

Daddy interrogates daughter to determine who is her favourite parent
Posted 8 years ago by boyt in category: funny   Comments (1)

Reducing the size of the travel box.
Posted 5 years ago by Chrissie10 in category: animals   Comments (0)