Patent US3171891A successfully refreshed from Google Patents.
US3171891A
Expired / Lapsed
US
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Amplifier output circuit
Assignee: GTE Sylvania Inc
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Filing: 1960-12-15
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Granted: 1965-03-02
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Expires: 1980-12-15
Abstract
No abstract record available.
Inventors
- 👤 Amos Bernard
- 👤 Jesse H Lofton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:23
CPC Classifications
H; H04; H04S; H04S3/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
IN A MULTI-CHANNEL AMPLIFIER THE COMBINATION COMPRISING A SERIES COUPLED PAIR OF SIMILAR SPEAKER UNITS HAVING AN INTERMEDIATE TERMINAL, SAID SPEAKER UNITS PROVIDING MID AND HIGH RANGE AUDIO REPRODUCTION AND HAVING A RELATIVELY LOW IMPEDANCE TO FREQUENCIES ACROSS THE LOW END OF THE AUDIO RANGE, A FIRST AND SECOND CHANNEL OUTPUT CIRCUIT COUPLED IN SERIES AND HAVING A SECOND INTERMEDIATE TERMINAL, MEANS COUPLING SAID SERIES CONNECTED OUTPUT CIRCUITS IN PARALLEL WITH SAID SERIES CONNECTED SPEAKER UNITS, A THIRD SPEAKER PROVIDING AUDIO SIGNALS OVER THE LOW AND MIDDLE PORTION OF THE AUDIO RANGE, A VARIABLE RESISTANCE-CAPACITANCE IMPEDANCE COUPLED ACROSS SAID THIRD SPEAKER TO FORM A PARALLEL CIRCUIT, SAID CAPACITANCE HAVING A RELATIVELY LOW IMPEDANCE FOR MIDDLE AUDIO FREQUENCIES, AND MEANS COUPLING SAID LAST MENTIONED PARALLEL CIRCUIT BETWEEN SAID TWO INTERMEDIATE TERMINALS.
Claim 2
Dependent Claim
130 words
IN A MULTI-CHANNEL AMPLIFIER THE COMBINATION COMPRISING A SERIES COUPLED PAIR OF SIMILAR SPEAKER UNITS HAVING AN INTERMEDIATE TERMINAL, SAID SPEAKER UNITS PROVIDING MID AND HIGH RANGE AUDIO REPRODUCTION AND HAVING A RELATIVELY LOW IMPEDANCE TO FREQUENCIES ACROSS THE LOW END OF THE AUDIO RANGE, A FIRST AND SECOND CHANNEL OUTPUT CIRCUIT COUPLED IN SERIES AND HAVING A SECOND INTERMEDIATE TERMINAL, MEANS COUPLING SAID SERIES CONNECTED OUTPUT CIRCUITS IN PARALLEL WITH SAID SERIES CONNECTED SPEAKER UNITS, A THIRD SPEAKER PROVIDING AUDIO SIGNALS OVER THE LOW AND MIDDLE PORTION OF THE AUDIO RANGE, A VARIABLE RESISTANCE-CAPACITANCE IMPEDANCE COUPLED ACROSS SAID THIRD SPEAKER TO FORM A PARALLEL CIRCUIT, SAID CAPACITANCE HAVING A RELATIVELY LOW IMPEDANCE FOR MIDDLE AUDIO FREQUENCIES, AND MEANS COUPLING SAID LAST MENTIONED PARALLEL CIRCUIT BETWEEN SAID TWO INTERMEDIATE TERMINALS.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-03-01 | 1968-08-31 | 1969-03-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-01 | 1972-08-31 | 1973-03-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-01 | 1976-08-31 | 1977-03-02 | $7700.00 | Window Closed / Lapsed |