Abstract: A receiver 700 having an audio output device 326 is disclosed. The receiver 700 receives a carrier signal modulated with data, voice, or a combination of both. The receiver 700 includes a demodulator 708 for demodulating the received carrier signal. The demodulated audio signal 302 is coupled to a delay circuit 300 where it is delayed and coupled to a detector 318. The detector 318 detects the presence of data or voice in the demodulated audio signal 302 and mutes or unmutes the audio output device 326 respectively. The delay circuit 300 stops any portion of the data signal to reach the audio output device 326.

Abstract: A method (200) and apparatus (100)is provided for a radio having adjustable operating parameters to adjust at least one such adjustable operating parameter based on the current location of the radio. Operating parameters which may be so adjusted include, but are not limited to, the following: transmitting power, operating channel, operating band, modulation type, modulation index, frequency deviation, squelch setting, channel spacing, control channel (for trunked communications), noise blanker characteristic, and receive bandwidth. In another embodiment, transmissions by the radio can be inhibited as a function of the location when it is determined that the location is within a hazard area.

Abstract: A communication system 100 comprising a dispatch sub-system 100A, a plurality of transmitters 100B, and a plurality of mobile transceivers 100C is disclosed. An antenna coupler 410 and a location sensor 414 are coupled to one another via a coax cable 412. The bias current to the coupler is supplied by the location sensor 414 via the resistor 406. A detector 200 measures the voltage across the resistor 406 which is relative to the current flowing in to the antenna coupler 410. The detector 200 compares the measured voltage via comparators 218 and 238 and determines if the measured voltage is beyond a certain boundary. The NOR gate 244 routes the comparison result to a MPU 250. The MPU 250 processes the result and transmits a signal to a base station 104 via the mobile transceiver 118. The base station 104 decodes the received signal and presents it to a dispatch center 106.