US3739283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of communicating warning information via the intermediate frequency of a superheterodyne radio and/or television receiver
Assignee: Individual
•
Filing: 1971-12-02
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Granted: 1973-06-12
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Expires: 1991-12-02
Abstract
Abstract A method of communicating warning information via the intermediate frequency of a superheterodyne radio and/or television receiver. A separate intermediate frequency signal bearing warning information, such as a tone, is transmitted and is received at a receiver simultaneously with reception of a conventionally modulated carrier signal. The separate intermediate frequency signal bypasses the mixer and the local oscillator of the receiver and is fed directly into the intermediate frequency amplifier of the receiver and through the intermediate frequency detector to provide the warning information in audio or visual form for the radio or television user.
Inventors
- 👤 F Colligan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:14
CPC Classifications
G; G08; G08B; G08B27/00; G08B27/008
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
151 words
In the method of operation of a communication system involving transmission of an information-bearing modulated carrier signal, reception of said modulated carrier signal, heterodyning of said modulated carrier signal by means of a mixer and a local oscillator to form an intermediate frequency signal, and amplifying and detecting of said intermediate signal by means of an intermediate frequency amplifier and detector to provide audio or visual information, the improvement of simultaneously communicating additional information comprising the steps of generating a separate and additional information-bearing signal at said intermediate frequency, transmitting said separate intermediate frequency signal, receiving said separate intermediate frequency signal simultaneously with said reception of said modulated carrier signal, bypassing said mixer and said local oscillator with said separate intermediate frequency signal, receiving said separate intermediate frequency signal at said intermediate frequency amplifier, and detecting said separate intermediate frequency signal to provide said additional information in audio or visual form.
Claim 2
Dependent Claim
151 words
In the method of operation of a communication system involving transmission of an information-bearing modulated carrier signal, reception of said modulated carrier signal, heterodyning of said modulated carrier signal by means of a mixer and a local oscillator to form an intermediate frequency signal, and amplifying and detecting of said intermediate signal by means of an intermediate frequency amplifier and detector to provide audio or visual information, the improvement of simultaneously communicating additional information comprising the steps of generating a separate and additional information-bearing signal at said intermediate frequency, transmitting said separate intermediate frequency signal, receiving said separate intermediate frequency signal simultaneously with said reception of said modulated carrier signal, bypassing said mixer and said local oscillator with said separate intermediate frequency signal, receiving said separate intermediate frequency signal at said intermediate frequency amplifier, and detecting said separate intermediate frequency signal to provide said additional information in audio or visual form.
Claim 3
Dependent Claim
40 words
A method of simultaneously communicating different information as in claim 1 furtheR including the step of passing said second intermediate frequency signal through an intermediate frequency filter prior to receiving said separate intermediate frequency signal at said intermediate frequency amplifier.
Claim 4
Dependent Claim
29 words
A method of simultaneously communicating different information as in claim 1 wherein said information-bearing modulated carrier signal and said additional information-bearing separate intermediate frequency signal are transmitted via cable.
Claim 5
Dependent Claim
22 words
A method as in claim 3 wherein said modulated carrier signal and said separate intermediate frequency signal are transmitted from separate locations.
Claim 6
Dependent Claim
26 words
A method as in claim 1 wherein said modulated carrier signal and said separate intermediate frequency signal are broadcast by transmission from at least one location.
Claim 7
Dependent Claim
27 words
A method as in claim 5 wherein said modulated carrier signal and said separate intermediate frequency signal are broadcast by transmission from separate antennas at different locations.
Claim 8
Dependent Claim
16 words
A method as in claim 1 wherein said separate intermediate frequency signal is a warning signal.
Claim 9
Dependent Claim
24 words
A method as in claim 1 wherein the frequency of said intermediate frequency signals is 262 kilocycles, 455 kilocycles, 10.7 megacycles, or 41.25 megacycles.
Claim 10
Dependent Claim
18 words
A method as in claim 1 wherein said separate intermediate frequency signal is modulated prior to its transmission.
References Cited (Backward Citations)
US3562650A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |