Patent US4395995A successfully refreshed from Google Patents.
Patent US3103635A successfully refreshed from Google Patents.
US3103635A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transistor tone control circuit
Assignee: Packard Bell Electronics Corp
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Filing: 1959-05-11
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Granted: 1963-09-10
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Expires: 1979-05-11
Abstract
No abstract record available.
Inventors
- 👤 Richard E Campbell
- 👤 Melvin H Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:12
CPC Classifications
H; H03; H03G; H03G5/00; H03G5/02; H03G5/04; H03G5/10; H03G5/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
389 words
A TRANSISTOR TONE CONTROL CIRCUIT FOR AUDIO FREQUENCY SIGNALS, INCLUDING, A FIRST TRANSISTOR AMPLIFIER INCLUDING A FIRST TRANSISTOR HAVING AN EMITTER AND A COLLECTOR, FIRST ADJUSTABLE IMPEDANCE MEANS CONNECTED TO THE COLLECTOR OF THE TRANSISTOR IN SAID FIRST TRANSISTOR AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE LOWER FREQUENCIES OF THE AUDIO FREQUENCY SIGNALS TO SELECTIVELY ADJUST THE FREQUENCY RESPONSE OF SAID FIRST TRANSISTOR AMPLIFIER TO THE AUDIO FREQUENCY SIGNALS, A DEGENERATING CIRCUIT CONNECTED TO THE EMITTER OF THE TRANSISTOR IN SAID FIRST TRANSISTOR AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE LOWER FREQUENCIES OF THE AUDIO SIGNALS TO SET THE GAIN OF SAID FIRST AMPLIFIER AT A PARTICULAR VALUE AT A PARTICULAR FREQUENCY BETWEEN THE LOWER AND THE HIGHER FREQUENCIES OF THE AUDIO SIGNALS AND COOPERATIVE WITH THE ADJUSTABLE IMPEDANCE MEANS TO PROVIDE A PARTICULAR GAIN AT A PARTICULAR CUT-OFF FREQUENCY AND TO COMPENSATE FOR CHANGES IN THE IMPEDANCE PRESENTED TO THE FIRST TRANSISTOR AMPLIFIER AND TO PROVIDE A VARIABLE IMPEDANCE IN ACCORDANCE WITH THE ADJUSTMENT OF THE FIRST IMPEDANCE MEANS AND IN ACCORDANCE WITH THE PARTICULAR FREQUENCY OF THE SIGNALS, A SECOND TRANSISTOR AMPLIFIER COUPLED TO SAID FIRST TRANSISTOR AMPLIFIER AND INCLUDING A SECOND TRANSISTOR HAVING AN EMITTER AND A COLLECTOR, THE SECOND TRANSISTOR AMPLIFIER BEING CONSTRUCTED TO PROVIDE A VARIABLE AMPLIFICATION IN ACCORDANCE WITH THE VARIABLE IMPEDANCE PROVIDED BY THE FIRST TRANSISTOR AMPLIFIER, SECOND ADJUSTABLE IMPEDANCE MEANS CONNECTED TO THE COLLECTOR OF THE TRANSISTOR IN SAID SECOND TRANSISTOR AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE UPPER FREQUENCIES OF THE AUDIO FREQUENCY SIGNALS TO SELECTIVELY ADJUST THE FREQUENCY RESPONSE OF SAID SECOND TRANSISTOR AMPLIFIER OF THE AUDIO FREQUENCY SIGNALS, AND A DEGENERATING EMITTER CIRCUIT CONNECTED TO THE EMITTER OF THE TRANSISTOR IN SAID SECOND AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE LOWER FREQUENCIES OF THE AUDIO SIGNALS AND COOPERATIVE WITH THE SECOND ADJUSTABLE IMPEDANCE MEANS TO PROVIDE THE PARTICULAR GAIN AT THE PARTICULAR CUT-OFF FREQUENCY AND TO COMPENSATE FOR CHANGES IN THE IMPEDANCE PRESENTED TO THE SECOND TRANSISTOR AMPLIFIER AND TO PROVIDE A VARIABLE IMPEDANCE IN ACCORDANCE WITH THE ADJUSTMENT OF THE SECOND IMPEDANCE MEANS AND IN ACCORDANCE WITH THE PARTICULAR FREQUENCY OF THE SIGNALS, SAID DEGENERATING CIRCUIT IN SAID SECOND AMPLIFIER BEING PROVIDED WITH CHARACTERISTICS FOR A GREATER DEGENERATION AT SAID PREDETERMINED FREQUENCY THAN THAT PROVIDED BY SAID DEGENERATION CIRCUIT IN SAID FIRST AMPLIFIER.
Claim 2
Dependent Claim
389 words
A TRANSISTOR TONE CONTROL CIRCUIT FOR AUDIO FREQUENCY SIGNALS, INCLUDING, A FIRST TRANSISTOR AMPLIFIER INCLUDING A FIRST TRANSISTOR HAVING AN EMITTER AND A COLLECTOR, FIRST ADJUSTABLE IMPEDANCE MEANS CONNECTED TO THE COLLECTOR OF THE TRANSISTOR IN SAID FIRST TRANSISTOR AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE LOWER FREQUENCIES OF THE AUDIO FREQUENCY SIGNALS TO SELECTIVELY ADJUST THE FREQUENCY RESPONSE OF SAID FIRST TRANSISTOR AMPLIFIER TO THE AUDIO FREQUENCY SIGNALS, A DEGENERATING CIRCUIT CONNECTED TO THE EMITTER OF THE TRANSISTOR IN SAID FIRST TRANSISTOR AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE LOWER FREQUENCIES OF THE AUDIO SIGNALS TO SET THE GAIN OF SAID FIRST AMPLIFIER AT A PARTICULAR VALUE AT A PARTICULAR FREQUENCY BETWEEN THE LOWER AND THE HIGHER FREQUENCIES OF THE AUDIO SIGNALS AND COOPERATIVE WITH THE ADJUSTABLE IMPEDANCE MEANS TO PROVIDE A PARTICULAR GAIN AT A PARTICULAR CUT-OFF FREQUENCY AND TO COMPENSATE FOR CHANGES IN THE IMPEDANCE PRESENTED TO THE FIRST TRANSISTOR AMPLIFIER AND TO PROVIDE A VARIABLE IMPEDANCE IN ACCORDANCE WITH THE ADJUSTMENT OF THE FIRST IMPEDANCE MEANS AND IN ACCORDANCE WITH THE PARTICULAR FREQUENCY OF THE SIGNALS, A SECOND TRANSISTOR AMPLIFIER COUPLED TO SAID FIRST TRANSISTOR AMPLIFIER AND INCLUDING A SECOND TRANSISTOR HAVING AN EMITTER AND A COLLECTOR, THE SECOND TRANSISTOR AMPLIFIER BEING CONSTRUCTED TO PROVIDE A VARIABLE AMPLIFICATION IN ACCORDANCE WITH THE VARIABLE IMPEDANCE PROVIDED BY THE FIRST TRANSISTOR AMPLIFIER, SECOND ADJUSTABLE IMPEDANCE MEANS CONNECTED TO THE COLLECTOR OF THE TRANSISTOR IN SAID SECOND TRANSISTOR AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE UPPER FREQUENCIES OF THE AUDIO FREQUENCY SIGNALS TO SELECTIVELY ADJUST THE FREQUENCY RESPONSE OF SAID SECOND TRANSISTOR AMPLIFIER OF THE AUDIO FREQUENCY SIGNALS, AND A DEGENERATING EMITTER CIRCUIT CONNECTED TO THE EMITTER OF THE TRANSISTOR IN SAID SECOND AMPLIFIER AND PROVIDED WITH CHARACTERISTICS FOR ATTENUATING THE LOWER FREQUENCIES OF THE AUDIO SIGNALS AND COOPERATIVE WITH THE SECOND ADJUSTABLE IMPEDANCE MEANS TO PROVIDE THE PARTICULAR GAIN AT THE PARTICULAR CUT-OFF FREQUENCY AND TO COMPENSATE FOR CHANGES IN THE IMPEDANCE PRESENTED TO THE SECOND TRANSISTOR AMPLIFIER AND TO PROVIDE A VARIABLE IMPEDANCE IN ACCORDANCE WITH THE ADJUSTMENT OF THE SECOND IMPEDANCE MEANS AND IN ACCORDANCE WITH THE PARTICULAR FREQUENCY OF THE SIGNALS, SAID DEGENERATING CIRCUIT IN SAID SECOND AMPLIFIER BEING PROVIDED WITH CHARACTERISTICS FOR A GREATER DEGENERATION AT SAID PREDETERMINED FREQUENCY THAN THAT PROVIDED BY SAID DEGENERATION CIRCUIT IN SAID FIRST AMPLIFIER.
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) | 1966-09-09 | 1967-03-11 | 1967-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-09-09 | 1971-03-11 | 1971-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-09-09 | 1975-03-11 | 1975-09-10 | $7700.00 | Window Closed / Lapsed |