US4031329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time limited telephone paging employs a relay switch actuated by dual frequency tone
Assignee: Nokia of America Corp
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Filing: 1976-04-02
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Granted: 1977-06-21
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Expires: 1996-04-02
Abstract
Abstract There is disclosed an arrangement to enable control of a function at a remote location from a local location employing two audio control signals (tones) each having a different frequency. A short burst of the two tones are injected into a telephone line at the local location. These two tones when detected simultaneously at the remote location provides an output signal from logic circuitry. This output signal triggers a timer whose output controls the function for a given period of time.
Inventors
- 👤 B. Ronald Saxon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:15
CPC Classifications
H; H04; H04M; H04M11/00; H04M11/02; H04M11/022; H04M11/007
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
249 words
An arrangement to control a loud speaker system at a remote location from a local location comprising: a telephone line having a given operating frequency band interconnecting said local location to said remote location; said loud speaker system being normally disconnected from said telephone line; a first source of a first audio control signal disposed at said local location, said first audio control signal having a first given frequency; a second source of a second audio control signal disposed at said local location, said second audio control signal having a second given frequency different than said first given frequency; first means coupled between said first and second sources and said telephone line at said local location to inject a short burst of said first and second audio control signals simultaneously into said operating frequency band of said telephone line; second means coupled to said telephone line at said remote location to detect both said first and second audio control signals and provide only a logic "1" output signal only when both of said first and second audio control signals are detected simultaneously; and third means coupled to said second means responsive to said output signal to actuate a relay and a contact thereof which connects said loud speaker system to said telephone line for a given period of time after cessation of said first and second audio control signals to enable said loud speaker system to broadcast a page message transmitted on said telephone line from said local location.
Claim 2
Dependent Claim
249 words
An arrangement to control a loud speaker system at a remote location from a local location comprising: a telephone line having a given operating frequency band interconnecting said local location to said remote location; said loud speaker system being normally disconnected from said telephone line; a first source of a first audio control signal disposed at said local location, said first audio control signal having a first given frequency; a second source of a second audio control signal disposed at said local location, said second audio control signal having a second given frequency different than said first given frequency; first means coupled between said first and second sources and said telephone line at said local location to inject a short burst of said first and second audio control signals simultaneously into said operating frequency band of said telephone line; second means coupled to said telephone line at said remote location to detect both said first and second audio control signals and provide only a logic "1" output signal only when both of said first and second audio control signals are detected simultaneously; and third means coupled to said second means responsive to said output signal to actuate a relay and a contact thereof which connects said loud speaker system to said telephone line for a given period of time after cessation of said first and second audio control signals to enable said loud speaker system to broadcast a page message transmitted on said telephone line from said local location.
Claim 3
Dependent Claim
22 words
An arrangement according to claim 1, wherein each of said first and second sources includes a phase locked loop audio signal generator.
Claim 4
Dependent Claim
86 words
An arrangement according to claim 2, wherein said first means includes fourth means to combine said first and second audio control signals, a switching means coupled between said fourth means and said telephone line, and a first timer coupled to said switching means, said first timer being actuated by a calling party to actuate said switching means for a short period of time to inject said short burst of said first and second audio control signals simultaneously into said operating frequency band of said telephone line.
Claim 5
Dependent Claim
72 words
An arrangement according to claim 3, further including fifth means coupled to one of said first and second sources to produce an audio signal having a third given frequency different than said first and second given signals to be injected into said operating frequency band of said telephone line by said switching means to indicate said telephone line is in use even in the absence of communication traffic on said telephone line.
Claim 6
Dependent Claim
46 words
An arrangement according to claim 4, wherein said fourth means includes a low pass filter having a given cut-off frequency coupled between said first and second sources and said switching means to combine said first and second audio control signal for application to said switching means.
Claim 7
Dependent Claim
70 words
An arrangement according to claim 5, wherein said second means includes a first detector coupled to said telephone line to detect said first audio control signal, a second detector coupled to said telephone line to detect said second audio control signal, and logic circuitry coupled to said first and second detectors to provide said output signal only when both of said first and second audio control signals are detected simultaneously.
Claim 8
Dependent Claim
40 words
An arrangement according to claim 6, wherein said third means includes a second timer coupled to said logic circuitry responsive to said output signal to control said loud speaker system at said remote location for said given period of time.
Claim 9
Dependent Claim
26 words
An arrangement according to claim 7, wherein said second means further includes a coupling network coupled between said telephone line and said first and second detectors.
Claim 10
Dependent Claim
64 words
An arrangement according to claim 8, wherein said coupling network includes a series circuit having a first resistor and a first capacitor coupled between said telephone line and said first and second detectors, and a parallel circuit coupled between the junction of said first resistor and said first capacitor and ground, said parallel circuit having a second capacitor, a second resistor and a varistor.
Claim 11
Dependent Claim
22 words
An arrangement according to claim 6, wherein each of said first and second detectors includes a phase locked loop audio signal detector.
Claim 12
Dependent Claim
14 words
An arrangement according to claim 10, wherein said logic circuitry includes a NOR gate.
Claim 13
Dependent Claim
40 words
An arrangement according to claim 11, wherein said third means includes a second timer coupled to said NOR gate responsive to said output signal to control said loud speaker system at said remote location for said given period of time.
Claim 14
Dependent Claim
26 words
An arrangement according to claim 12, wherein said second means further includes a coupling network coupled between said telephone line and said first and second detectors.
Claim 15
Dependent Claim
64 words
An arrangement according to claim 13, wherein said coupling network includes a series circuit having a first resistor and a first capacitor coupled between said telephone line and said first and second detectors, and a parallel circuit coupled between the junction of said first resistor and said first capacitor and ground, said parallel circuit having a second capacitor, a second resistor and a varistor.
Claim 16
Dependent Claim
70 words
An arrangement according to claim 1, wherein said second means includes a first detector coupled to said telephone line to detect said first audio control signal, a second detector coupled to said telephone line to detect said second audio control signal, and logic circuitry coupled to said first and second detectors to provide said output signal only when both of said first and second audio control signals are detected simultaneously.
Claim 17
Dependent Claim
33 words
An arrangement according to claim 15, wherein said third means includes a timer coupled to said logic circuitry responsive to said output signal to actuate said relay for said given period of time.
Claim 18
Dependent Claim
26 words
An arrangement according to claim 16, wherein said second means further includes a coupling network coupled between said telephone line and said first and second detectors.
Claim 19
Dependent Claim
64 words
An arrangement according to claim 17, wherein said coupling network includes a series circuit having a first resistor and a first capacitor coupled between said telephone line and said first and second detectors, and a parallel circuit coupled between the junction of said first resistor and said first capacitor and ground, said parallel circuit having a second capacitor, a second resistor and a varistor.
Claim 20
Dependent Claim
22 words
An arrangement according to claim 15, wherein each of said first and second detectors includes a phase locked loop audio signal detector.
Claim 21
Dependent Claim
14 words
An arrangement according to claim 19, wherein said logic circuitry includes a NOR gate.
Claim 22
Dependent Claim
33 words
An arrangement according to claim 20, wherein said third means includes a timer coupled to said NOR gate responsive to said output signal to actuate said relay for said given period of time.
Claim 23
Dependent Claim
26 words
An arrangement according to claim 21, wherein said second means further includes a coupling network coupled between said telephone line and said first and second detectors.
Claim 24
Dependent Claim
64 words
An arrangement according to claim 22, wherein said coupling network includes a series circuit having a first resistor and a first capacitor coupled between said telephone line and said first and second detectors, and a parallel circuit coupled between the junction of said first resistor and said first capacitor and ground, said parallel circuit having a second capacitor, a second resistor and a varistor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-06-20 | 1980-12-20 | 1981-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-20 | 1984-12-20 | 1985-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-20 | 1988-12-20 | 1989-06-21 | $7700.00 | Window Closed / Lapsed |