A Christmas tree, PCB ornament

It is soon Christmas and I am facing the very same, yearly recurring problem: What gifts to buy! I generally prefer gifts to have a personal touch and was always fascinated by some personalized keychains I would receive from my uncle who has a milling machine. This Christmas, I did some timely planning and created a bunch of interactive electronic ornaments, shaped like Christmas trees! These gadgets are perfect for the occasion: They are festive, easy to make, special and with the help of my newly acquired 3D printer, they can be personalized! Before beginning, I compiled a set of requirements the system should satisfy”

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