RECONFIGURABLE ANTENNAS AND RF FRONT ENDS FOR PORTABLE WIRELESS DEVICES

A reversible sprocket assembly for a chain and sprocket drive system includes a sprocket body having an inner hub portion with a central bore and an outer sprocket drive unit including teeth for engaging a drive chain. A coupling, such as mating splines, is provided along the bore for coupling the sprocket in driving relationship with the drive shaft. The coupling is reversible so that the bore of the hub may be received on the shaft with either end first. A counterbore is provided at each end of the hub adjacent the coupling so as to form end portions of the bore. When mounted on the shaft, one counterbore mates with a first shoulder on the shaft. A removable annular spacer forms a second shoulder to mate with the other counterbore. In this way, the sprocket body is securely supported in driving relationship on the shaft. By reversing the sprocket drive unit as a whole, the trailing faces of the teeth become the new drive faces and the life of the sprocket assembly is essentially doubled.