US3110868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistor hearing aid amplifier
Assignee: Sonotone Corp
•
Filing: 1959-06-16
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Granted: 1963-11-12
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Expires: 1979-06-16
Abstract
No abstract record available.
Inventors
- 👤 Harry A Pearson
- 👤 Frank A Herrmann
- 👤 William H Greenbaum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:06
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/181; H03F3/183; H03F3/50; H04; H04R; H04R25/00; H03F2200/00; H03F2200/03; H03F2200/534; H03F2200/537; H03F2200/541; H04R2225/00; H04R2225/59; H04R2225/61
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
202 words
IN A TRANSISTOR AMPLIFIER OF A DEVICE SUCH AS A HEARING AID WORN ON THE BODY OF THE USER, HAVING A PLURALITY OF TRANSISTOR AMPLIFIER STAGES AND A BATTERY SUPPLY HAVING TWO SUPPLY TERMINALS FOR ENERGIZING SAID AMPLIFIER STAGES: A FIRST STAGE HAVING A FIRST TRANSISTOR, CIRCUIT MEANS FOR CONNECTING AN ELECTROMAGNETIC SIGNAL SOURCE TO THE INPUT SIDE OF SAID FIRST TRANSISTOR; A SECOND STAGE HAVING A SECOND TRANSISTOR AND AN INTERSTAGE COUPLING TRANSFORMER HAVING ITS PRIMARY WINDING CONNECTED TO THE OUTPUT SIDE OF SAID FIRST TRANSISTOR AND ITS SECONDARY WINDING CONNECTED TO THE INPUT SIDE OF SAID SECOND TRANSISTOR; THE EMITTERS OF SAID TWO TRANSISTORS BEING CONNECTED TO ONE SUPPLY TERMINAL AND THE COLLECTORS OF SAID TWO TRANSISTORS BEING CONNECTED TO THE OTHER SUPPLY TERMINAL; SAID SECOND TRANSISTOR BEING CONNECTED TO SAID SECONDARY WINDING THROUGH A SERIES CIRCUIT SECTION INCLUDING AT LEAST TWO SERIALLY CONNECTED CAPACITORS; AND CONTROL MEANS INCLUDING AT LEAST A PORTION OF SAID SERIES CIRCUIT SECTION AND OPERATIVE TO SELECTIVELY EFFECT PREDETERMINED FREQUENCY RESPONSE CHANGES FOR BELOW THE MID-BAND FREQUENCIES OF THE AUDIO-FREQUENCY RANGE; SAID CONTROL MEANS INCLUDING A CONTROL RESISTANCE SELECTIVELY CONNECTIBLE ACROSS AT LEAST ONE CAPACITOR OF SAID SERIES CIRCUIT SECTION AND CONSTITUTING THEREWITH A FILTER
Claim 2
Dependent Claim
202 words
IN A TRANSISTOR AMPLIFIER OF A DEVICE SUCH AS A HEARING AID WORN ON THE BODY OF THE USER, HAVING A PLURALITY OF TRANSISTOR AMPLIFIER STAGES AND A BATTERY SUPPLY HAVING TWO SUPPLY TERMINALS FOR ENERGIZING SAID AMPLIFIER STAGES: A FIRST STAGE HAVING A FIRST TRANSISTOR, CIRCUIT MEANS FOR CONNECTING AN ELECTROMAGNETIC SIGNAL SOURCE TO THE INPUT SIDE OF SAID FIRST TRANSISTOR; A SECOND STAGE HAVING A SECOND TRANSISTOR AND AN INTERSTAGE COUPLING TRANSFORMER HAVING ITS PRIMARY WINDING CONNECTED TO THE OUTPUT SIDE OF SAID FIRST TRANSISTOR AND ITS SECONDARY WINDING CONNECTED TO THE INPUT SIDE OF SAID SECOND TRANSISTOR; THE EMITTERS OF SAID TWO TRANSISTORS BEING CONNECTED TO ONE SUPPLY TERMINAL AND THE COLLECTORS OF SAID TWO TRANSISTORS BEING CONNECTED TO THE OTHER SUPPLY TERMINAL; SAID SECOND TRANSISTOR BEING CONNECTED TO SAID SECONDARY WINDING THROUGH A SERIES CIRCUIT SECTION INCLUDING AT LEAST TWO SERIALLY CONNECTED CAPACITORS; AND CONTROL MEANS INCLUDING AT LEAST A PORTION OF SAID SERIES CIRCUIT SECTION AND OPERATIVE TO SELECTIVELY EFFECT PREDETERMINED FREQUENCY RESPONSE CHANGES FOR BELOW THE MID-BAND FREQUENCIES OF THE AUDIO-FREQUENCY RANGE; SAID CONTROL MEANS INCLUDING A CONTROL RESISTANCE SELECTIVELY CONNECTIBLE ACROSS AT LEAST ONE CAPACITOR OF SAID SERIES CIRCUIT SECTION AND CONSTITUTING THEREWITH A FILTER
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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) | 1966-11-11 | 1967-05-13 | 1967-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-11-11 | 1971-05-13 | 1971-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-11-11 | 1975-05-13 | 1975-11-12 | $7700.00 | Window Closed / Lapsed |