The invention relates to a handheld analyzer for testing a sample, in particular of a biological fluid, for a medically significant component. It comprises a test unit, which detects the correct positioning of an analytical consumable means in a conveyance pathway. According to this invention, the test unit has both an electric switch component which mechanically senses the positioning of the analytical consumable means and an optical sensor unit which optically senses the positioning of the analytical consumable means on the conveyance pathway. The handheld analyzer is controlled as a function of a comparison of the signals of the electric switch component and the optical sensor unit. It is possible in this way to reduce malfunctions or operating errors associated therewith.