Patent US3083264A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3083264A Expired / Lapsed US ⏱️ 0.0 years remaining

Sum and difference stereophonic transmission with negative feedback

Assignee: AT&T Inc
•
Filing: 1959-12-10
•
Granted: 1963-03-26
•
Expires: 1979-12-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

No abstract record available.

Inventors

  • 👤 William T Wintringham

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 06:35
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)

US2062275A Cited
US2093540A Cited
US2845491A Cited
US2904632A Cited

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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag