US3199028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual feedback direct frequency modulation system
Assignee: Collins Radio Co
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Filing: 1962-08-06
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Granted: 1965-08-03
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Expires: 1982-08-06
Abstract
No abstract record available.
Inventors
- 👤 Frank D Mclin
- 👤 Glenn W Sellers
- 👤 David B Hallock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:01
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/44; H04H20/46; H04H20/47; H04H20/48; H03; H03C; H03C3/00; H03C3/10; H03C3/12; H03C3/22; H03C3/222
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
138 words
A DIRECT FREQUENCY MODULATION SYSTEM INCLUDING CARRIER FREQUENCY STABILIZING MEANS, SAID SYSTEM COMPRISING: AN OSCILLATOR HAVING A VOLTAGE SENSITIVE OUTPUT FREQUENCY DETERMINING NETWORK THAT IS BIASED TO ESTABLISH A PREDETERMINED OPERATIONAL CARRIER FREQUENCY; MEANS ADAPTED TO RECEIVE MODULATING SIGNALS OVER A WIDE RANGE OF FREQUENCIES AND COUPLE THE SAME TO SAID FREQUENCY DETERMINING NETWORK TO CAUSE SAID OSCILLATOR TO BE FREQUENCY MODULATED THEREBY; AND FIRST AND SECOND FEEDBACK NETWORKS CONNECTED IN PARALLEL BETWEEN THE OUTPUT OF SAID OSCILLATOR AND SAID FREQUENCY DETERMINING NETWORK WHEREBY SAID CARRIER FREQUENCY, EXCLUSIVE OF MODULATION THEREON, IS MAINTAINED SUBSTANTIALLY CONSTANT, AND WHEREIN SAID FIRST FEEDBACK LOOP INCLUDES MEANS WHEREBY SAID RECEIVED MODULATING SIGNALS ARE FED BACK TO SUPPRESS OSCILLATOR DISTORTION, NOISE, AND SHORT TERM CARRIER FREQUENCY SHIFTS, AND WHEREIN SAID SECOND FEEDBACK LOOP INCLUDES MEANS WHEREBY LONG TERM CARRIER FREQUENCY SHIFTS ARE SUPPRESSED.
Claim 2
Dependent Claim
138 words
A DIRECT FREQUENCY MODULATION SYSTEM INCLUDING CARRIER FREQUENCY STABILIZING MEANS, SAID SYSTEM COMPRISING: AN OSCILLATOR HAVING A VOLTAGE SENSITIVE OUTPUT FREQUENCY DETERMINING NETWORK THAT IS BIASED TO ESTABLISH A PREDETERMINED OPERATIONAL CARRIER FREQUENCY; MEANS ADAPTED TO RECEIVE MODULATING SIGNALS OVER A WIDE RANGE OF FREQUENCIES AND COUPLE THE SAME TO SAID FREQUENCY DETERMINING NETWORK TO CAUSE SAID OSCILLATOR TO BE FREQUENCY MODULATED THEREBY; AND FIRST AND SECOND FEEDBACK NETWORKS CONNECTED IN PARALLEL BETWEEN THE OUTPUT OF SAID OSCILLATOR AND SAID FREQUENCY DETERMINING NETWORK WHEREBY SAID CARRIER FREQUENCY, EXCLUSIVE OF MODULATION THEREON, IS MAINTAINED SUBSTANTIALLY CONSTANT, AND WHEREIN SAID FIRST FEEDBACK LOOP INCLUDES MEANS WHEREBY SAID RECEIVED MODULATING SIGNALS ARE FED BACK TO SUPPRESS OSCILLATOR DISTORTION, NOISE, AND SHORT TERM CARRIER FREQUENCY SHIFTS, AND WHEREIN SAID SECOND FEEDBACK LOOP INCLUDES MEANS WHEREBY LONG TERM CARRIER FREQUENCY SHIFTS ARE SUPPRESSED.
References Cited (Backward Citations)
US2550519A
Cited
US2789211A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-08-02 | 1969-02-01 | 1969-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-08-02 | 1973-02-01 | 1973-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-08-02 | 1977-02-01 | 1977-08-03 | $7700.00 | Window Closed / Lapsed |