I got one of the parts I’ll be repurposing for the bracelet in the mail today: a Proxgrind ChameleonTiny Professional, supplied by the good people at KSEC Solutions.
Why that thing you ask?
Well, it has everything I need: it’s not much bigger than a piece of candy, it’s extremely light, it runs on battery, it can output an unmodulated 13.56 MHz carrier wave with a decent amount of power, the field can be turned on and off, it can be controlled over BLE, and the firmware is open-source. It really has all the features I need right out of the box.
Check out its performances. Not too shabby for a sugar lump:
All it needs is an external antenna and some code from yours truly, to transmit messages from a cellphone.
As for the bracelet proper, I’m waiting for a batch of PCL plastic to start shaping that - hopefully nice-looking, but I wouldn’t be too hopeful, as I’m not a very artsy kind of person.