Heineken speaker crate

[rollatorwieltje]

So someone gave me this Heinkeken speaker crate. It claims to be a "near field audio amplifier". You basically play some audio on your phone and then place it on top of the box, with the phone speaker over the music note symbol. It actually works surprisingly well. Could actually be useful for conference calls if your phone doesn't have a reasonable speaker.

At first I thought it was just a microphone, but it wouldn't actually respond to any audio at all, except my phone. So it turns out it doesn't use a microphone, it actually amplifies magnetic fields detected by those 2 coils. Not just music of course, it can also detect mains wiring in walls and other magnetic fields

The USB port is just for charging, there's a small LiPo pack inside.