Telecommunications – Transmitter and receiver at separate stations
Patent
1995-11-13
1998-01-13
Eisenzopf, Reinhard J.
Telecommunications
Transmitter and receiver at separate stations
455 79, 455 89, 455212, 455352, 340539, 340573, 340692, H04Q 902
Patent
active
057089701
ABSTRACT:
In a wireless sound monitoring system, ambient sounds are monitored by a microphone and transmitted over a phase or frequency modulated transmitter to a receiver. A sound actuated switch responsive to ambient sounds louder than a predetermined level turns the transmitter on and causes a hidden tone to be generated. A delay circuit caused the hidden tone to be terminated before the transmitter is turned off when the sound level decreases. In the receiver, a mute circuit responds to the hidden tone to control the output of a loudspeaker, and thus, the hidden tone prevents a squelch tail from being heard. The monitoring unit also includes a pulse generator to cause the hidden tones to be generated at regular intervals, but with short pulse widths. In the receiver, a mute delay circuit prevents the un-muting of the loudspeaker in response to these short pulses, but as long as the hidden tone pulses are detected within a predetermined period of time, a visual indicator, an LED, will light to show the proper operation of the system. Each hidden tone detected will cause the LED to blink momentarily; however, if the hidden tones are not detected, the LED will be extinguished and a distinctive audio tone will be generated to alert the user.
REFERENCES:
patent: 3810023 (1974-05-01), Crowley et al.
patent: 4101872 (1978-07-01), Pappas
patent: 4103105 (1978-07-01), Akiyama et al.
patent: 4484355 (1984-11-01), Henke et al.
patent: 4598272 (1986-07-01), Cox
patent: 4622544 (1986-11-01), Bially et al.
patent: 4785291 (1988-11-01), Hawthorne
patent: 4899135 (1990-02-01), Ghahariiran
patent: 4996717 (1991-02-01), Koening
patent: 5119072 (1992-06-01), Hemingway
patent: 5307051 (1994-04-01), Sedlmayr
patent: 5534851 (1996-07-01), Russek
Freese Theodore B.
Lindenberger Gary C.
Newman Perran V. L.
Crouch Robert G.
Eisenzopf Reinhard J.
Gerry Baby Products
Sobutka Philip J.
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