Why do earbuds ring when going through electronic detectors?



Whenever I walk into the library I am more often than not listening to music with either earphones or AirPods as do my friends. Whenever walking through the anti-theft gate a high pitched ringing emanates from the audio device. Just wondering why the gate causes this to happen.

In: Technology

Those detectors work by sending an electromagnetic pulse, and listening for feedback which occurs when an activated anti theft tag enters their field. It’s likely the Bluetooth antenna being vibrated.

The gates themselves use radio waves to detect the anti theft tags, using a very basic form of radio frequency identification. The signal or sends out is tuned to a specific frequency, which is what activates the tags in a library or in a shop. What is most likely happening is that this signal is being picked up and the bit of the ear pods that is making the sound reproduces it, so you hear it as a ringing sound.