The NCS-C250 is an interoperability controller designed especially for mobile installations such as mobile command posts, incident command vehicles and other emergency response vehicles. The unit provides a single point interface that allows the radio operator to control the transmit audio, receive audio, and the push-to-talk function of up to four radio transceivers. A single microphone or headset can be used to communicate through all radios eliminating the need for multiple microphones. Separate speaker outputs for selected and unselected audio along with individual volume controls and mute buttons reduce operator fatigue and confusion. Features include a PA function, built-in cross band repeater/range extender and flexible muting functions.