US3867700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tone operated single side-band communication system
Assignee: Individual
•
Filing: 1973-11-21
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Granted: 1975-02-18
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Expires: 1993-11-21
Abstract
Abstract The system includes a transmitter in which is provided a tone generator having a first oscillator to generate a first signal of a fixed frequency and a second oscillator which is variable to generate a second signal of a selected frequency. A multiplier receives the signals and provides a pair of tones having frequencies respectively equal to the sum of and difference between their frequencies. A switch may be provided so that both inputs to the multiplier are received from the variable frequency oscillator, in which case the output of the multiplier will be a single tone having a frequency twice that of the signal produced by the variable frequency oscillator. In either event, the tones are modulated on an RF wave. The system further comprises a receiver which has processing apparatus to receive incoming single side-band signals and convert them into IF components. A product detector in conjunction with an IF carrier source is operated to detect the IF signal and provide an intelligence message contained therein. A loudspeaker converts the intelligence message into audio information. An AM detector mixes the single side-band components to provide a signal having a frequency equal to the difference in frequencies between the tones in the incoming single side-band signals. A tuned circuit is responsive to a difference frequency signal of a predetermined frequency to provide an output signal to operate an electronic switch. In the presence of the output signal, the electronic switch produces an enabling signal to render the audio circuit operative and also to render the product detector operative and to render the AM detector inoperative. In the absence of the enabling signal, the audio circuit is inoperative as is the product detector but the AM detector is operative.
Inventors
- 👤 Keith H Wycoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:32
CPC Classifications
H; H03; H03B; H03B21/00; H03B21/01; H04; H04B; H04B1/00; H04B1/68
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
284 words
A communication receiver for receiving incoming single sideband signals modulated by two simultaneous tones lasting for a predetermined duration and by a subsequent intelligence message, said receiver comprising processing means for receiving the incoming signals and providing an IF signal including single side-band components corresponding to the two simultaneous tones and to the intelligence message, circuit means including an IF carrier source and product detector means coupled to said IF carrier source and to said processing means and being operative to detect the IF signal and thereby provide the intelligence message, an audio circuit coupled to said product detector and including transducer means for converting the intelligence message, AM detector means coupled to said processing means for mixing the single side-band components in the IF signal to provide a difference frequency signal having a frequency equal to the difference in frequency between the tones, a tuned circuit coupled to said AM detector means for providing an output signal when the difference frequency signal has a predetermined frequency, electronic switching means coupled to said tuned circuit and responsive to the output signal for providing an enabling signal which extends beyond termination of the tones, first means coupled to said switching means for rendering said audio circuit operative to furnish an output in accordance with the intelligence message in the presence of the enabling signal and for rendering said audio circuit inoperative in the absence of said enabling signal, and second means coupled to said switching means for rendering said circuit means operative and said AM detector means inoperative in the presence of the enabling signal and for rendering said circuit means inoperative and said AM detector means operative in the absence of the enabling signal.
Claim 2
Dependent Claim
284 words
A communication receiver for receiving incoming single sideband signals modulated by two simultaneous tones lasting for a predetermined duration and by a subsequent intelligence message, said receiver comprising processing means for receiving the incoming signals and providing an IF signal including single side-band components corresponding to the two simultaneous tones and to the intelligence message, circuit means including an IF carrier source and product detector means coupled to said IF carrier source and to said processing means and being operative to detect the IF signal and thereby provide the intelligence message, an audio circuit coupled to said product detector and including transducer means for converting the intelligence message, AM detector means coupled to said processing means for mixing the single side-band components in the IF signal to provide a difference frequency signal having a frequency equal to the difference in frequency between the tones, a tuned circuit coupled to said AM detector means for providing an output signal when the difference frequency signal has a predetermined frequency, electronic switching means coupled to said tuned circuit and responsive to the output signal for providing an enabling signal which extends beyond termination of the tones, first means coupled to said switching means for rendering said audio circuit operative to furnish an output in accordance with the intelligence message in the presence of the enabling signal and for rendering said audio circuit inoperative in the absence of said enabling signal, and second means coupled to said switching means for rendering said circuit means operative and said AM detector means inoperative in the presence of the enabling signal and for rendering said circuit means inoperative and said AM detector means operative in the absence of the enabling signal.
Claim 3
Dependent Claim
42 words
The communication receiver set forth in claim 1, wherein said processing means includes an antenna for receiving the incoming signals, an RF carrier source, and a converter coupled to said RF carrier source and to said antenna for providing the IF signal.
Claim 4
Dependent Claim
23 words
The communication receiver set forth in claim 1, wherein said transducer means is a loudspeaker for converting the intelligence message into sound waves.
Claim 5
Dependent Claim
21 words
The communication receiver set forth in claim 1, wherein said tuned circuit is tuned to a frequency in the voice spectrum.
Claim 6
Dependent Claim
36 words
The communication receiver set forth in claim 1, wherein the enabling signal provided by said electronic switching means continues indefinitely beyond the termination of the tones, and further comprising reset means for terminating said enabling signal.
Claim 7
Dependent Claim
31 words
The communication receiver set forth in claim 1, wherein said first and second means are pairs of contacts of a relay having a relay winding coupled to said electronic switching means.
Claim 8
Dependent Claim
30 words
The communication receiver set forth in claim 1, and further comprising alerting means coupled to said electronic switching means and responsive to the enabling signal to provide an alerting signal.
Claim 9
Dependent Claim
48 words
A communication receiver set forth in claim 1, wherein and further comprising third means coupled to said switching means for rendering said IF carrier source operative in the presence of the enabling signal and for rendering said IF carrier source inoperative in the absence of the enabling signal.
Claim 10
Dependent Claim
322 words
A communication receiver for receiving incoming single side-band signals modulated by two simultaneous tones lasting for a predetermined duration and by a subsequent intelligence message, said receiver comprising processing means for receiving the incoming signals and providing an IF signal including single side-band components corresponding to the two simultaneous tones and to the intelligence message, circuit means including an IF carrier source and product detector means coupled to said IF carrier source said to said processing means and being operative to detect the IF signal and thereby provide the intelligence message, an audio circuit coupled to said product detector and including transducer means for converting the intelligence message, AM detector means coupled to said processing means for mixing the single side-band components in the IF signal to provide a difference frequency signal having a frequency equal to the difference in frequency between the tones, audio amplifier means coupled to said product detector means and to said AM detector means for amplifying the intelligence message and the difference frequency signal, transducer means coupled to said audio amplifier means for converting the intelligence message, a tuned circuit coupled to said audio amplifier means for providing an output signal when the difference frequency signal has a predetermined frequency, electronic switching means coupled to said tuned circuit and responsive to the output signal for providing an enabling signal which extends beyond termination of the tones, first means coupled to said switching means for rendering said audio circuit operative to furnish an output in accordance with the intelligence message in the presence of the enabling signal and for rendering said audio circuit inoperative in the absence of said enabling signal, and second means coupled to said switching means for rendering said circuit means operative and said AM detector means inoperative in the presence of the enabling signal and for rendering said circuit means inoperative and said AM detector means operative in the absence of the enabling signal.
Claim 11
Dependent Claim
322 words
A communication receiver for receiving incoming single side-band signals modulated by two simultaneous tones lasting for a predetermined duration and by a subsequent intelligence message, said receiver comprising processing means for receiving the incoming signals and providing an IF signal including single side-band components corresponding to the two simultaneous tones and to the intelligence message, circuit means including an IF carrier source and product detector means coupled to said IF carrier source said to said processing means and being operative to detect the IF signal and thereby provide the intelligence message, an audio circuit coupled to said product detector and including transducer means for converting the intelligence message, AM detector means coupled to said processing means for mixing the single side-band components in the IF signal to provide a difference frequency signal having a frequency equal to the difference in frequency between the tones, audio amplifier means coupled to said product detector means and to said AM detector means for amplifying the intelligence message and the difference frequency signal, transducer means coupled to said audio amplifier means for converting the intelligence message, a tuned circuit coupled to said audio amplifier means for providing an output signal when the difference frequency signal has a predetermined frequency, electronic switching means coupled to said tuned circuit and responsive to the output signal for providing an enabling signal which extends beyond termination of the tones, first means coupled to said switching means for rendering said audio circuit operative to furnish an output in accordance with the intelligence message in the presence of the enabling signal and for rendering said audio circuit inoperative in the absence of said enabling signal, and second means coupled to said switching means for rendering said circuit means operative and said AM detector means inoperative in the presence of the enabling signal and for rendering said circuit means inoperative and said AM detector means operative in the absence of the enabling signal.
Claim 12
Dependent Claim
50 words
The communication receiver set forth in claim 9, wherein the output of said processing means is continuously applied both to said product detector means and to said AM detector means, and the outputs of said product detector and said AM detector means are continuously applied to said audio amplifier means.
Claim 13
Dependent Claim
330 words
A communication receiver for receiving incoming single side-band signals modulated by two simultaneous tones lasting for a predetermined duration and by a subsequent intelligence message, said receiver comprising processing means for receiving the incoming signals and providing an IF signal incluDing single side-band components corresponding to the two simultaneous tones and to the intelligence message, circuit means including an IF carrier source and product detector means coupled to said IF carrier source and to said processing means and being operative to detect the IF signal and thereby provide the intelligence message, an audio circuit coupled to said product detector and including transducer means for converting the intelligence message, AM detector means coupled to said processing means for mixing the single side-band components in the IF signal to provide a difference frequency signal having a frequency equal to the difference in frequency between the tones, a tuned circuit coupled to said AM detector means for providing an output signal when the difference frequency signal has a predetermined frequency, electronic switching means coupled to said tuned circuit and responsive to the output signal for providing a first enabling signal which extends indefinitely beyond termination of the tones and a second enabling signal which extends a predetermined duration beyond termination of the tones, first means coupled to said electronic switching means for rendering said audio circuit operative to furnish an output in accordance with the intelligence message in the presence of the first enabling signal and for rendering said audio circuit inoperative in the absence of said first enabling signal, second means coupled to said switching means for rendering said circuit means operative and said AM detector means inoperative in the presence of the first enabling signal and for rendering said circuit means inoperative and said AM detector means operative in the absence of the first enabling signal, and alerting means coupled to said electronic switching means for producing an alerting signal for said predetermined duration in response to said second enabling signal.
Claim 14
Dependent Claim
330 words
A communication receiver for receiving incoming single side-band signals modulated by two simultaneous tones lasting for a predetermined duration and by a subsequent intelligence message, said receiver comprising processing means for receiving the incoming signals and providing an IF signal incluDing single side-band components corresponding to the two simultaneous tones and to the intelligence message, circuit means including an IF carrier source and product detector means coupled to said IF carrier source and to said processing means and being operative to detect the IF signal and thereby provide the intelligence message, an audio circuit coupled to said product detector and including transducer means for converting the intelligence message, AM detector means coupled to said processing means for mixing the single side-band components in the IF signal to provide a difference frequency signal having a frequency equal to the difference in frequency between the tones, a tuned circuit coupled to said AM detector means for providing an output signal when the difference frequency signal has a predetermined frequency, electronic switching means coupled to said tuned circuit and responsive to the output signal for providing a first enabling signal which extends indefinitely beyond termination of the tones and a second enabling signal which extends a predetermined duration beyond termination of the tones, first means coupled to said electronic switching means for rendering said audio circuit operative to furnish an output in accordance with the intelligence message in the presence of the first enabling signal and for rendering said audio circuit inoperative in the absence of said first enabling signal, second means coupled to said switching means for rendering said circuit means operative and said AM detector means inoperative in the presence of the first enabling signal and for rendering said circuit means inoperative and said AM detector means operative in the absence of the first enabling signal, and alerting means coupled to said electronic switching means for producing an alerting signal for said predetermined duration in response to said second enabling signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |