A portable tire prep detector is used to detect prep on a tire, when the tire is on a racing vehicle, and when the racing vehicle is on a race track. The stem has an upper end portion to face a proximal side and a backside to face a greater trochanter and is adapted for insertion into, and fixation to, a medullary space of a femur. In addition, a coil winding start end and winding finish end of the field coil are led out through a valley portion between first claw-shaped magnetic pole portions, and are respectively connected to projecting portions of the connecting terminals. An evaluation value input screen shows selected documents and permits the operator to enter an evaluation value to each of the displayed selected documents. A check is carried out to determine whether to output a first security note via the first terminal.