US3158690A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fm time division multiplex system having inputs superimposed with positive and negative d. c. voltages
Assignee: Loewe Opta GmbH
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Filing: 1961-04-03
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Granted: 1964-11-24
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Expires: 1981-04-03
Abstract
No abstract record available.
Inventors
- 👤 Frank Egon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:52
CPC Classifications
H; H04; H04H; H04H20/00; H04H20/44; H04H20/46; H04H20/47; H04H20/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
113 words
IN A FREQUENCY MODULATION TRANSMISSION SYSTEM USING TWO LOW-FREQUENCY SIGNALS ON A COMMON HIGH FREQUENCY CARRIER ACCORDING TO THE TIME MULTIPLEX SYSTEM FOR COMPATIBLE TWO-CHANNEL STEREOPHONIC TRANSMISSION, COMPRISING A TRANSMITTER AND AT LEAST ONE RECEIVER, SAID TRANSMITTER HAVING A STEREOPHONIC PRE-MODULATOR, CONTAINING A FREQUENCY MODULATOR AND MEANS FOR SWITCHING IN TURN IN SUPERSONIC FREQUENCY THE FIRST LOW-FREQUENCY SIGNAL REPRESENTING THE LEFT AUDIO INFORMATION WITH A SUPERIMPOSED POSITIVE DIRECT VOLTAGE AND THEN THE SECOND LOWFREQUENCY SIGNAL REPRESENTING THE RIGHT AUDIO INFORMATION WITH A SUPERIMPOSED NEGATIVE DIRECT VOLTAGE TO SAID FREQUENCY MODULATOR USING A VARIABLE SUB-CARRIER AMPLITUDE, MEANS FOR INCREASING THE SUM SIGNAL PORTION OF BOTH SAID LOW-FREQUENCY SIGNALS AND OF REDUCING THE DIFFERENCE SIG-
Claim 2
Dependent Claim
113 words
IN A FREQUENCY MODULATION TRANSMISSION SYSTEM USING TWO LOW-FREQUENCY SIGNALS ON A COMMON HIGH FREQUENCY CARRIER ACCORDING TO THE TIME MULTIPLEX SYSTEM FOR COMPATIBLE TWO-CHANNEL STEREOPHONIC TRANSMISSION, COMPRISING A TRANSMITTER AND AT LEAST ONE RECEIVER, SAID TRANSMITTER HAVING A STEREOPHONIC PRE-MODULATOR, CONTAINING A FREQUENCY MODULATOR AND MEANS FOR SWITCHING IN TURN IN SUPERSONIC FREQUENCY THE FIRST LOW-FREQUENCY SIGNAL REPRESENTING THE LEFT AUDIO INFORMATION WITH A SUPERIMPOSED POSITIVE DIRECT VOLTAGE AND THEN THE SECOND LOWFREQUENCY SIGNAL REPRESENTING THE RIGHT AUDIO INFORMATION WITH A SUPERIMPOSED NEGATIVE DIRECT VOLTAGE TO SAID FREQUENCY MODULATOR USING A VARIABLE SUB-CARRIER AMPLITUDE, MEANS FOR INCREASING THE SUM SIGNAL PORTION OF BOTH SAID LOW-FREQUENCY SIGNALS AND OF REDUCING THE DIFFERENCE SIG-
References Cited (Backward Citations)
US1914570A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1967-11-24 | 1968-05-25 | 1968-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-11-24 | 1972-05-25 | 1972-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-11-24 | 1976-05-25 | 1976-11-24 | $7700.00 | Window Closed / Lapsed |