US3077519A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stereophonic phonograph
Assignee: Wurlitzer Co
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Filing: 1959-11-17
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Granted: 1963-02-12
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Expires: 1979-11-17
Abstract
No abstract record available.
Inventors
- 👤 John H Riggs
- 👤 Robert D Barry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:51
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
209 words
IN A PHONOGRAPH FOR PLAYING STEREOPHONIC RECORDS AND AUTOMATICALLY COMPENSATING FOR THE INHERENT LOUDNESS OF INDIVIDUAL RECORDS, THE COMBINATION OF TWO SIGNAL AMPLIFIERS, AN ELECTRICAL PICK-UP UNIT HAVING TWO SEPARATE ELECTRICAL OUTPUTS CONNECTED TO SAID RESPECTIVE AMPLIFIERS TO CONTROL THE LATTER, TWO SIGNAL ATTENUATING RESISTORS COUPLED TO THE OUTPUTS OF SAID RESPECTIVE AMPLIFIERS, AN AVERAGING CIRCUIT COUPLED TO THE OUTPUT OF ONLY ONE OF SAID SIGNAL AMPLIFIERS AHEAD OF THE COACTING RESISTOR, SAID AVERAGING CIRCUIT INCLUDING CIRCUIT MEANS FOR PRODUCING AN INSTANTANEOUS ELECTRICAL OUTPUT WHICH IS A FUNCTION OF THE AVERAGE SIGNAL VOLTAGE OF SAID ONE SIGNAL AMPLIFIER OVER AN EXTENDED PERIOD OF TIME, TWO ELECTRONIC DISCHARGE VALVES CONNECTED TO THE OUTPUTS OF SAID RESPECTIVE SIGNAL AMPLIFIERS THROUGH SAID RESPECTIVE RESISTORS, TWO POWER AMPLIFIERS HAVING INPUTS COUPLED THROUGH SAID RESPECTIVE RESISTORS WITH SAID RESPECTIVE SIGNAL AMPLIFIERS, ELECTRICAL SOUND PRODUCING MEANS CONNECTED TO SAID RESPECTIVE POWER AMPLIFIERS AND MEANS COUPLING THE UTPUT OF SAID AVERAGING CIRCUIT TO BOTH OF SAID DISCHARGE VALVES TO CONTROL THE ADMITTANCES OF BOTH VALVES AT ONCE IN ACCORDANCE WITH THE OUTPUT OF SAID AVERAGING CIRCUIT TO PRODUCE A CONTINUOUS MODULATION OF THE SIGNAL ATTENUATING EFFECT OF BOTH OF SAID RESISTORS SIMULTANEOUSLY TO COMPENSATE FOR PROLONGED CHANGES IN THE AVERAGE OUTPUT OF SAID ONE SIGNAL AMPLIFIER.
Claim 2
Dependent Claim
209 words
IN A PHONOGRAPH FOR PLAYING STEREOPHONIC RECORDS AND AUTOMATICALLY COMPENSATING FOR THE INHERENT LOUDNESS OF INDIVIDUAL RECORDS, THE COMBINATION OF TWO SIGNAL AMPLIFIERS, AN ELECTRICAL PICK-UP UNIT HAVING TWO SEPARATE ELECTRICAL OUTPUTS CONNECTED TO SAID RESPECTIVE AMPLIFIERS TO CONTROL THE LATTER, TWO SIGNAL ATTENUATING RESISTORS COUPLED TO THE OUTPUTS OF SAID RESPECTIVE AMPLIFIERS, AN AVERAGING CIRCUIT COUPLED TO THE OUTPUT OF ONLY ONE OF SAID SIGNAL AMPLIFIERS AHEAD OF THE COACTING RESISTOR, SAID AVERAGING CIRCUIT INCLUDING CIRCUIT MEANS FOR PRODUCING AN INSTANTANEOUS ELECTRICAL OUTPUT WHICH IS A FUNCTION OF THE AVERAGE SIGNAL VOLTAGE OF SAID ONE SIGNAL AMPLIFIER OVER AN EXTENDED PERIOD OF TIME, TWO ELECTRONIC DISCHARGE VALVES CONNECTED TO THE OUTPUTS OF SAID RESPECTIVE SIGNAL AMPLIFIERS THROUGH SAID RESPECTIVE RESISTORS, TWO POWER AMPLIFIERS HAVING INPUTS COUPLED THROUGH SAID RESPECTIVE RESISTORS WITH SAID RESPECTIVE SIGNAL AMPLIFIERS, ELECTRICAL SOUND PRODUCING MEANS CONNECTED TO SAID RESPECTIVE POWER AMPLIFIERS AND MEANS COUPLING THE UTPUT OF SAID AVERAGING CIRCUIT TO BOTH OF SAID DISCHARGE VALVES TO CONTROL THE ADMITTANCES OF BOTH VALVES AT ONCE IN ACCORDANCE WITH THE OUTPUT OF SAID AVERAGING CIRCUIT TO PRODUCE A CONTINUOUS MODULATION OF THE SIGNAL ATTENUATING EFFECT OF BOTH OF SAID RESISTORS SIMULTANEOUSLY TO COMPENSATE FOR PROLONGED CHANGES IN THE AVERAGE OUTPUT OF SAID ONE SIGNAL 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) | 1966-02-11 | 1966-08-13 | 1967-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-02-11 | 1970-08-13 | 1971-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-02-11 | 1974-08-13 | 1975-02-12 | $7700.00 | Window Closed / Lapsed |