The Beyerdynamic Quinta MU 21 V delegate microphone unit is equipped with one microphone button in the housing with which the participant can switch the microphone on and off as well as two additional buttons, which can be activated for voting. When a voting takes place, the microphone unit is switched into the voting mode where the three buttons (Yes, No, Abstain) are available for parliamentary votings, Multiple Choice or Opinion Polls. The actual operating mode is displayed via colored backlit buttons. With the Automatic Channel Allocation function the transmitting channels of the microphone units are allocated automatically. When the microphone button is pressed in the manual operating mode the request-to-talk is received by the control unit (a possible external dual colour LED will illuminate red). Then the control unit checks which of the available receiving channels is free. Then the control unit informs the microphone unit which channel it should use for transmitting. When the channel of the microphone unit is set and checked by the control unit, the microphone is switched on. The ready-to-talk status of the microphone is also indicated by the red LED ring around the gooseneck microphone. In the Requestto-Talk-mode of the discussion system the request-to-talk is received, but the microphone is not switched on. The red LED indicates that the request-to-talk has been received. The microphone is switched on by the operator at the PC by using the "Quinta Conference" software or a media control system. When the microphone button is pressed once again, the delegate clears his/her request-to-talk.