A wireless data communication apparatus having a tamper resistant hardware package which includes a reconfigurable logic device which can be reconfigured in accordance with downloaded program, and a security check device for checking a software program. The external capture structure surface and retainer ring internal bore surface are both threaded for rotatable attachment within a cavity of the head. Still other advantages are made possible by the described technology. The measured data obtained with the first measurement is analyzed, and at least one parameter of the structure is thereby determined.