US3117186A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compatible stereophonic broadcast system
Assignee: Individual
•
Filing: 1960-02-17
•
Granted: 1964-01-07
•
Expires: 1980-02-17
Abstract
No abstract record available.
Inventors
- 👤 Richard W Burden
- 👤 William S Halstead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:37
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/86; H04H20/88
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
58 words
IN A STEREOPHONIC TRANSMISSION SYSTEM, MEANS FOR PRODUCING ONE STERO SIGNAL ON A FREQUENCY MODULATED MAIN CARRIER, MEANS FOR PRODUCING ANOTHER STEREO SIGNAL ON A FREQUENCY MODULATED SUBCARRIER, MEANS INCLUDING A DIFFERENTIAL AMPLIFIER FOR DERIVING FROM SAID STEREO SIGNALS A PAIR OF DIFFERENCE SIGNALS, AND MEANS FOR COMBINING EACH OF SAID DIFFERENCE SIGNALS WITH SAID ORIGINAL STEREO SIGNALS.
Claim 2
Dependent Claim
58 words
IN A STEREOPHONIC TRANSMISSION SYSTEM, MEANS FOR PRODUCING ONE STERO SIGNAL ON A FREQUENCY MODULATED MAIN CARRIER, MEANS FOR PRODUCING ANOTHER STEREO SIGNAL ON A FREQUENCY MODULATED SUBCARRIER, MEANS INCLUDING A DIFFERENTIAL AMPLIFIER FOR DERIVING FROM SAID STEREO SIGNALS A PAIR OF DIFFERENCE SIGNALS, AND MEANS FOR COMBINING EACH OF SAID DIFFERENCE SIGNALS WITH SAID ORIGINAL STEREO SIGNALS.
References Cited (Backward Citations)
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Cited
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Cited
US2352696A
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Cited
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Cited
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-01-06 | 1967-07-08 | 1968-01-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-01-06 | 1971-07-08 | 1972-01-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-01-06 | 1975-07-08 | 1976-01-07 | $7700.00 | Window Closed / Lapsed |