The invention discloses a blood analyzing device comprising a holder arranged for carrying a container having a cuvette containing a blood sample. The dental handpiece has a switching valve between the circumferential chip air channel and the chip air line in the handpiece body for selectively allowing and preventing communication. A first NMOS transistor is connected to the first PMOS transistor and the second PMOS transistor. Further, the communication device may comprise a bio-signal acquisition and amplifier component in communication with a user interface for providing the bio-signals as input to the user interface, the user interface controlling the setting or set of setting for operation of the communication device. Both doors pivot about horizontal axes to provide access to the warm compartment.