- Joined Oct 28, 2011
Hi everyone! The building I live in has doors which open only when i touch my " key fob " to a special box attached to the door. The key fob is a tiny oval grey device the size of a tootsie roll. My question is how does the key fob work? I broke open one of them and didnt see any battery. Nor did i see any antenna to communicate. how exactly do these things work? can some one explain to me please.thank you.