US3083264A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sum and difference stereophonic transmission with negative feedback
Assignee: AT&T Inc
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Filing: 1959-12-10
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Granted: 1963-03-26
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Expires: 1979-12-10
Abstract
No abstract record available.
Inventors
- 👤 William T Wintringham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:19
CPC Classifications
H; H04; H04S; H04S1/00; H04S1/002; H03; H03F; H03F1/00; H03F1/34; H03F1/36
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
139 words
IN A TWO-CHANNEL STEROPHONIC SYSTEM FOR AUDIBLY REPRODUCING A LEFT SOUND WAVE AND A RIGHT SOUND WAVE FROM RECEIVED SUM AND DIFFERENCE SIGNALS, A FIRST AMPLIFIER FOR AMPLIFYING AN INCOMING SUM SIGNAL, A SECOND AMPLIFIER FOR AMPLIFYING AN INCOMING DIFFERENCE SIGNAL, A LEFT REPRODUCER AND RIGHT REPRODUCER, EACH OF SAID REPRODUCERS HAVING TWO ELECTRICALLY INDEPENDENT DRIVING COILS THAT ARE MECHANICALLY COUPLED TOGETHER, CONNECTIONS FOR FEEDING SAID SUM SIGNAL AND SAID DIFFERENCE SIGNAL TO THE COILS OF SAID LEFT REPRODUCER IN A PREASSIGNED PHASE RELATION, AND CONNECTIONS FOR FEEDING SAID SUM SIGNAL AND SAID DIFFERENCE SIGNAL TO THE COILS OF SAID RIGHT REPRODUCER IN OPPOSITE PHASE RELATION, WHEREBY THE MOVEMENTS OF THE DIAPHRAGMS OF SAID REPRODUCERS IN RESPONSE TO THE CURRENTS IN THEIR COILS ACT TO RECOMBINE SAID SIGNALS AND TO REPRODUCE LEFT SOUND WAVES AND RIGHT SOUND WAVES, RESPECTIVELY.
Claim 2
Dependent Claim
139 words
IN A TWO-CHANNEL STEROPHONIC SYSTEM FOR AUDIBLY REPRODUCING A LEFT SOUND WAVE AND A RIGHT SOUND WAVE FROM RECEIVED SUM AND DIFFERENCE SIGNALS, A FIRST AMPLIFIER FOR AMPLIFYING AN INCOMING SUM SIGNAL, A SECOND AMPLIFIER FOR AMPLIFYING AN INCOMING DIFFERENCE SIGNAL, A LEFT REPRODUCER AND RIGHT REPRODUCER, EACH OF SAID REPRODUCERS HAVING TWO ELECTRICALLY INDEPENDENT DRIVING COILS THAT ARE MECHANICALLY COUPLED TOGETHER, CONNECTIONS FOR FEEDING SAID SUM SIGNAL AND SAID DIFFERENCE SIGNAL TO THE COILS OF SAID LEFT REPRODUCER IN A PREASSIGNED PHASE RELATION, AND CONNECTIONS FOR FEEDING SAID SUM SIGNAL AND SAID DIFFERENCE SIGNAL TO THE COILS OF SAID RIGHT REPRODUCER IN OPPOSITE PHASE RELATION, WHEREBY THE MOVEMENTS OF THE DIAPHRAGMS OF SAID REPRODUCERS IN RESPONSE TO THE CURRENTS IN THEIR COILS ACT TO RECOMBINE SAID SIGNALS AND TO REPRODUCE LEFT SOUND WAVES AND RIGHT SOUND WAVES, RESPECTIVELY.
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) | 1966-03-25 | 1966-09-24 | 1967-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-03-25 | 1970-09-24 | 1971-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-03-25 | 1974-09-24 | 1975-03-26 | $7700.00 | Window Closed / Lapsed |