Abstract: An apparatus for communicating using multiple channels. The apparatus includes a first radio receiver and a controller. The first radio receiver is configured to produce a first receive signal in response to a first radio frequency signal in a first frequency band. The controller has a first receive input for receiving the first receive signal, an audio input for receiving an audio in signal, a selector input for receiving a selector signal, an audio output for producing an audio out signal and a first transmitter output for producing a first transmitter signal. The first transmit output is configured for communication with a radio transmitter operable to transmit a second radio frequency signal in a second frequency band different from the first frequency band.

Abstract: A method of facilitating communicaons for a wearer of a mask, such as a firefighter's breathing apparatus, involves receiving a removable transmitter apparatus in a receptacle in the mask, to permit the transmitter apparatus to receive acoustic utterances made by the wearer of the mask and to transmit electromagnetic radiation representing the utterances for reception by a receiver. The receiver receives the electromagnetic radiation and broadcasts an audible reproduction of the acoustic utterances. The receiver may be supported by a wearer of the mask so that listeners in the vicinity of the wearer can hear the utterances. A plurality of wearers of masks may each have the apparatus described above to create a mobile public address system in which the utterances of a plurality of wearers may be broadcast from each wearer to other people in the vicinity of the wearers.