Abstract: A key mechanism is disclosed. A base plate includes a first pivoting portion and a second pivoting portion opposing the first pivoting portion. A keycap is disposed on the base plate and includes at least one engaging portion. A linking bar is connected between the base plate and the keycap and includes a first body portion, two second body portions, and two curved portions. The first body portion is rotatably engaged in the engaging portion of the keycap. The second body portions are connected to the first body portion and oppose each other. The curved portions are connected to the second body portions and pivot to the first and second pivoting portions of the base plate, respectively.

Abstract: A loop antenna system. The loop antenna system for a wireless transmission device having a signal end and a ground end, includes a loop antenna having a toroidal helix wire with a first end coupled to the signal end and a second end coupled to the ground end.