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US3136864A Expired / Lapsed US ⏱️ 0.0 years remaining

Loudspeaking telephone with electronic voice switching

Assignee: Automatic Electric Laboratories Inc
•
Filing: 1959-10-05
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Granted: 1964-06-09
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Expires: 1979-10-05
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Abstract

No abstract record available.

Inventors

  • 👤 Robert T Cleary

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-22 22:30
CPC Classifications
H; H04; H04M; H04M9/00; H04M9/08; H04M9/10

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 119 words
IN A TELEPHONE SYSTEM HAVING A TRANSMITTING CHANNEL AND A RECEIVING CHANNEL, A CONTROL CIRCUIT HAVING AN INPUT END AND AN OUTPUT END, TWO INPUT CONNECTIONS RESPECTIVELY EXTENDING FROM SAID TWO CHANNELS AND DIFFERENTIALLY CONNECTED TO SAID INPUT END, AND TWO OUTPUT CONNECTIONS RESPECTIVELY EXTENDING TO SAID CHANNELS FROM SAID OUTPUT END, SAID CONTROL CIRCUIT COMPRISING A DIODE-CAPACITANCE BRIDGE ARRANGEMENT INCLUDING A PAIR OF CAPACITANCE LEGS COMMON TO BOTH SAID CHANNELS AND TWO PAIRS OF DIODE LEGS FOR CONTROL OF SAID TRANSMITTING CHANNEL AND SAID RECEIVING CHANNEL RESPECTIVELY, SAID TWO PAIR OF DIODE LEGS RESPECTIVELY CAUSING THE SERIES IMPEDANCE OF ONE OF SAID CHANNELS AND THE SHUNT IMPEDANCE OF THE OTHER SAID CHANNEL TO VARY IN THE SAME SENSE.

References Cited (Backward Citations)

GB509613A Cited
US2282405A Cited
US2332430A Cited
US2468205A Cited
GB665274A Cited
US2885478A Cited
GB858678A Cited
US3022379A Cited
US3046354A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1967-06-09 1967-12-09 1968-06-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1971-06-09 1971-12-09 1972-06-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1975-06-09 1975-12-09 1976-06-09 $7700.00 Window Closed / Lapsed

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