The fold-away MCS-D 3821 built-in delegate microphone unit provides a microphone button and a two-way loudspeaker system. The operating mode of the microphone unit can be configured through the MCS-D 200 control unit or using iCNS software. In the standard mode (free switching on possible) the participant can use the microphone button to switch the microphone on and off. The LED on the microphone button signals that the microphone is ready to be used. If the maximum number of active microphones has been reached, the LED will only flash for a short time and the delegate must press the button once more. In the conference system's activation mode, the microphone button is used for entering a request to speak. This request is visually displayed by the flashing LED near the microphone button. Once the microphone has been enabled by the PC/media controller user or the president microphone unit, the LED stops flashing and is continuously lit. The delegate can deactivate the unit again by pressing the microphone button once more. If the maximum number of active microphones has been reached, the LED will only flash for a short time and the delegate must activate their microphone once again.