Patent US3120580A successfully refreshed from Google Patents.
US3120580A
Expired / Lapsed
US
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Stereo signal generator
Assignee: Calbest Engineering & Electron
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Filing: 1962-03-23
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Granted: 1964-02-04
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Expires: 1982-03-23
Abstract
No abstract record available.
Inventors
- 👤 Harold N Parker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:00
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/44; H04H20/46; H04H20/47; H04H20/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
IN A STEREO SIGNAL GENERATOR COOPERABLE WITH TWO AUDIO CHANNELS FOR TWO STEREO SIGNALS L AND R: CIRCUIT MEANS FOR DERIVING FROM SAID CHANNELS, A COMPOSITE SIGNAL CORRESPONDING TO THE ALGEBRAIC SUM OF L AND R, WHETHER DIFFERENTIAL OR CUMULATIVE; MEANS FOR PRODUCING A SUBCARRIER FOR MODULATION BY SAID COMPOSITE SIGNAL; A MODULATOR COOPERABLE WITH THE SUBCARRIER AND THE SAID COMPOSITE SIGNALS FOR PRODUCING SIDEBANDS OF SAID SUBCARRIER AS WELL AS FOR PASSING SAID COMPOSITE SIGNALS; MEANS FOR PRODUCING A SIGNAL FROM ONE OF SAID AUDIO CHANNELS CORRESPONDING TO TWICE ONE OF THE COMPONENTS OF SAID COMPOSITE SIGNAL, AND OF OPPOSITE PHASE; AND MEANS FOR COMBINING THE OUTPUT OF SAID MODULATOR WITH THE SIGNAL OF SAID SIGNAL PRODUCING MEANS.
Claim 2
Dependent Claim
119 words
IN A STEREO SIGNAL GENERATOR COOPERABLE WITH TWO AUDIO CHANNELS FOR TWO STEREO SIGNALS L AND R: CIRCUIT MEANS FOR DERIVING FROM SAID CHANNELS, A COMPOSITE SIGNAL CORRESPONDING TO THE ALGEBRAIC SUM OF L AND R, WHETHER DIFFERENTIAL OR CUMULATIVE; MEANS FOR PRODUCING A SUBCARRIER FOR MODULATION BY SAID COMPOSITE SIGNAL; A MODULATOR COOPERABLE WITH THE SUBCARRIER AND THE SAID COMPOSITE SIGNALS FOR PRODUCING SIDEBANDS OF SAID SUBCARRIER AS WELL AS FOR PASSING SAID COMPOSITE SIGNALS; MEANS FOR PRODUCING A SIGNAL FROM ONE OF SAID AUDIO CHANNELS CORRESPONDING TO TWICE ONE OF THE COMPONENTS OF SAID COMPOSITE SIGNAL, AND OF OPPOSITE PHASE; AND MEANS FOR COMBINING THE OUTPUT OF SAID MODULATOR WITH THE SIGNAL OF SAID SIGNAL PRODUCING MEANS.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-02-03 | 1967-08-05 | 1968-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-02-03 | 1971-08-05 | 1972-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-02-03 | 1975-08-05 | 1976-02-04 | $7700.00 | Window Closed / Lapsed |