A device (80) for reading a coded golf ball (40) comprises a helical track (82) on the inside or outside of a cylindrical housing (81), the track serving to change the orientation of the ball relative to an antenna coil (85) to ensure that the code is read. The track may be arranged horizontally and rotated by a motor; a flap (30) may be provided to avoid balls following each other too closely onto the helical track. Alternatively the track may be arranged vertically and the balls may fall under gravity.