US3231822A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency modulation feedback receiver
Assignee: AT&T Inc
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Filing: 1961-12-22
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Granted: 1966-01-25
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Expires: 1981-12-22
Abstract
No abstract record available.
Inventors
- 👤 Le Roy C Tillotson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:17
CPC Classifications
H; H03; H03D; H03D3/00; H03D3/001; H03D3/003; H03D3/004
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
91 words
IN A RECEIVER FOR FREQUENCY MODULATED WAVES, A VARIABLE FREQUENCY LOCAL OSCILLATOR, MEANS FOR COMBINING THE OUTPUT OF SAID LOCAL OSCILLATOR AND SAID FREQUENCY MODULATED WAVES TO PRDUCE AN INTERMEDIATE FREQUENCY SIGNAL, MEANS FOR AMPLIFYING AND DEMODULATING SAID INTERMEDIATE FREQUENCY SIGNAL, FEEDBACK MEANS INCLUDING A FREQUENCY RESTRICTIVE ELEMENT FOR APPLYING A PORTION OF THE DEMODULATED SIGNAL TO PRODUCE CORRESPONDING VARIATIONS IN THE FREQUENCY OF SAID LOCAL OSCILLATOR, AND MEANS FOR VARYING THE CLOSED LOOP BANDWITH OF THE FEEDBACK CIRCUIT AS A FUNCTION OF THE LEVEL OF THE APPLIED FREQUENCY MODULATED WAVES.
Claim 2
Dependent Claim
91 words
IN A RECEIVER FOR FREQUENCY MODULATED WAVES, A VARIABLE FREQUENCY LOCAL OSCILLATOR, MEANS FOR COMBINING THE OUTPUT OF SAID LOCAL OSCILLATOR AND SAID FREQUENCY MODULATED WAVES TO PRDUCE AN INTERMEDIATE FREQUENCY SIGNAL, MEANS FOR AMPLIFYING AND DEMODULATING SAID INTERMEDIATE FREQUENCY SIGNAL, FEEDBACK MEANS INCLUDING A FREQUENCY RESTRICTIVE ELEMENT FOR APPLYING A PORTION OF THE DEMODULATED SIGNAL TO PRODUCE CORRESPONDING VARIATIONS IN THE FREQUENCY OF SAID LOCAL OSCILLATOR, AND MEANS FOR VARYING THE CLOSED LOOP BANDWITH OF THE FEEDBACK CIRCUIT AS A FUNCTION OF THE LEVEL OF THE APPLIED FREQUENCY MODULATED WAVES.
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) | 1969-01-24 | 1969-07-26 | 1970-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-01-24 | 1973-07-26 | 1974-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-01-24 | 1977-07-26 | 1978-01-25 | $7700.00 | Window Closed / Lapsed |