| 摘要 |
<p>A transmitter/receiver system (2) for the simultaneous transmission and reception of plural audio signals over the air for a short range using carrier signals of frequencies over 900 MHz. A combined signal (100) having a plurality of carrier signals, each modulated by a different audio signal, is transmitted. The receiver (6), separated from the transmitter by a distance of 10 to 300 feet, receives the combined signal (100) and the listener then selects one of the frequency modulated carrier signals in the combined signal (100) at the receiver (6) with a selector switch (18). One of a set of combined signals is selected at the transmitter (4), allowing for a choice of different frequencies for transmission, to avoid interference with other systems in the vicinity. Moreover, where predetermined, e.g., fault, conditions occur in the transmitter (4) and/or receiver (6), muting circuits (158) within the receiver (6) are activated for the duration of the predetermined, e.g. fault, condition.</p> |
