US3125641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for indicating stereophonic broadcasting
Assignee: —
•
Filing: —
•
Granted: 1964-03-17
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Expires: 1981-03-17
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 01:25
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/1646; H04B1/1653
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
165 words
APPARATUS FOR INDICATING THE TRANSMISSION OF A FREQUENCY MODULATED CARRIER CONTAINING A PILOT-FREQUENCY MODULATION, SAID APPARATUS HAVING, IN COMBINATION, A TUNER FOR RECEIVING AND DETECTING THE CARRIER, A FILTER TUNED TO THE PILOT FREQUENCY AND CONNECTED TO THE TUNER FOR EXTRACTING THE PILOT FREQUENCY FROM THE DETECTED CARRIER, THE FILTER PRODUCING NOISE IN ITS OUTPUT AS AN AMPLITUDE MODULATION OF THE PILOT FREQUENCY DURING THE RECEPTION OF THE SAME AND AS A NOISE SIGNAL ALONE IN THE ABSENCE OF RECEPTION OF THE PILOT FREQUENCY, FIRST RECTIFYING MEANS CONNECTED WITH THE FILTER FOR PRODUCING A DIRECT-CURRENT COMPONENT OF THE OUTPUT THEREOF, FURTHER RECTIFYING MEANS CONNECTED WITH THE FILTER FOR DETECTING THE NEGATIVE MODULATION PEAK COMPONENTS OF THE SAID AMPLITUDE MODULATION OF THE PILOT FREQUENCY DURING THE RECEPTION OF THE SAME, A MIXING CIRCUIT FOR SUBTRACTING THE SAID DIRECT-CURRENT AND NEGATIVE MODULTION PEAK COMPONENTS, AND INDICATING MEANS CONNECTED WITH THE MIXING CIRCUIT FOR PRODUCING A DIRECT CURRENT OUTPUT SUBSTANTIALLY PROPORTIONED TO THE SAID NEGATIVE MODULATION PEAK COMPONENTS.
Claim 2
Dependent Claim
165 words
APPARATUS FOR INDICATING THE TRANSMISSION OF A FREQUENCY MODULATED CARRIER CONTAINING A PILOT-FREQUENCY MODULATION, SAID APPARATUS HAVING, IN COMBINATION, A TUNER FOR RECEIVING AND DETECTING THE CARRIER, A FILTER TUNED TO THE PILOT FREQUENCY AND CONNECTED TO THE TUNER FOR EXTRACTING THE PILOT FREQUENCY FROM THE DETECTED CARRIER, THE FILTER PRODUCING NOISE IN ITS OUTPUT AS AN AMPLITUDE MODULATION OF THE PILOT FREQUENCY DURING THE RECEPTION OF THE SAME AND AS A NOISE SIGNAL ALONE IN THE ABSENCE OF RECEPTION OF THE PILOT FREQUENCY, FIRST RECTIFYING MEANS CONNECTED WITH THE FILTER FOR PRODUCING A DIRECT-CURRENT COMPONENT OF THE OUTPUT THEREOF, FURTHER RECTIFYING MEANS CONNECTED WITH THE FILTER FOR DETECTING THE NEGATIVE MODULATION PEAK COMPONENTS OF THE SAID AMPLITUDE MODULATION OF THE PILOT FREQUENCY DURING THE RECEPTION OF THE SAME, A MIXING CIRCUIT FOR SUBTRACTING THE SAID DIRECT-CURRENT AND NEGATIVE MODULTION PEAK COMPONENTS, AND INDICATING MEANS CONNECTED WITH THE MIXING CIRCUIT FOR PRODUCING A DIRECT CURRENT OUTPUT SUBSTANTIALLY PROPORTIONED TO THE SAID NEGATIVE MODULATION PEAK COMPONENTS.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-03-17 | 1967-09-16 | 1968-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-03-17 | 1971-09-16 | 1972-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-03-17 | 1975-09-16 | 1976-03-17 | $7700.00 | Window Closed / Lapsed |