Emergency radio frequency warning device
OwnerWilliam S. Sadlerinventor
Life of this patent
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Abstract
An electronic whistle in the form of broad band radio frequency interference generator. A broad band generator generates a coherent or random noise signal which is modulated by an audio signal which corresponds to an audible warning signal such as a whistle or a siren. The modulated signal is then utilized to modulate a carrier signal and amplified and transmitted so that the radios in vehicles in the immediate area will receive an audible interference signal regardless of the particular channel to which the radio is tuned. The audible interference signal may be an intelligible reproduction of the input audio signal so that the driver of the vehicle can determine whether the warning signal is generated by a train whistle, a siren or a human voice.
Claims10
A radio frequency safety device comprising means for generating a noise signal having a broad frequency band, means for generating an RF signal, means responsive to an audio frequency signal for sweeping said RF signal generating means through a predetermined band at an audio rate, means for modulating said broad band noise signal with said RF signal, means for generating a carrier signal, and means for modulating said carrier signal with said modulated noise signal to thereby generate a broad band radio interference signal which generates an audible signal when received by a radio receiver, wherein said audible signal is a recognizable reproduction of said audio signal.
A radio frequency device comprising means for generating a signal having a broad frequency band, means for generating an RF signal, means responsive to an audio frequency signal for sweeping said RF signal generating means through a predetermined band at an audio rate, means for modulating said broad band signal with said RF signal, means for generating a carrier signal, and means for modulating said carrier signal with said modulated broad band signal to thereby generate a broad band radio interference signal which generates an audio signal when received by an audio receiver.
A radio frequency device comprising means for generating a signal having a broad frequency band, means for generating an RF signal, means responsive to an audio frequency signal for sweeping said RF signal generating means through a predetermined band at an audio rate, means for generating a carrier signal, means for amplitude modulating said carrier signal with said modulated broad band signal to thereby generate a broad band amplitude modulated radio interference signal for interfering with the commercial AM broadcast band, said interference signal generating an audible signal when detected by a radio receiver.
A radio frequency safety device comprising means for generating a signal having a broad frequency band, means for generating an RF signal, means responsive to an audio frequency signal for sweeping said RF signal generating means through a predetermined band at an audio rate, means for generating a carrier signal, means for frequency modulating said carrier signal with said modulated broad band signal to thereby generate a frequency modulated broad band radio interference signal for interference with the commercial FM broadcast band, said interference signal generating an audible signal when detected by a radio.
Dependencies are inferred from the claim text.