Patent US3921086A successfully refreshed from Google Patents.
US3921086A
Expired / Lapsed
US
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Demodulator circuit for amplitude-modulated signals including diodes with like poles interconnected and a current source biasing the diodes in their forward conducting direction
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1973-12-18
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Granted: 1975-11-18
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Expires: 1993-12-18
Abstract
Abstract A demodulation circuit for amplitude-modulated electrical signals includes at least two diodes having like poles interconnected with each other, the diodes being biased in their forward conducting direction such that the sum of the diode currents remains constant. The other poles of the diodes are connected to an input signal source of low impedance through a center tapped transformer winding or a choke coil.
Inventors
- 👤 Alois Marek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:56
CPC Classifications
H; H03; H03D; H03D1/00; H03D1/02; H03D1/06; H03D1/08; H03D1/10
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
92 words
A demodulation circuit for amplitude-modulated electrical signals which includes at least two diodes having a pair of like poles thereof interconnected with each other, a current source connected to said diodes for biasing said diodes in their forward conducting direction such that the sum of the diode currents remains constant, and means connecting the other pair of like poles of said diodes to an input signal source whose impedance is low in relation to the differential resistance of one of said diodeS at the forward biasing current provided by said current source.
Claim 2
Dependent Claim
92 words
A demodulation circuit for amplitude-modulated electrical signals which includes at least two diodes having a pair of like poles thereof interconnected with each other, a current source connected to said diodes for biasing said diodes in their forward conducting direction such that the sum of the diode currents remains constant, and means connecting the other pair of like poles of said diodes to an input signal source whose impedance is low in relation to the differential resistance of one of said diodeS at the forward biasing current provided by said current source.
Claim 3
Dependent Claim
32 words
A demodulation circuit as defined in claim 1 wherein said current source for biasing said diodes is connected between a junction point of the interconnection between said diodes and a reference potential.
Claim 4
Dependent Claim
62 words
A demodulation circuit as defined in claim 1 wherein the demodulator has a one-way drive, and wherein said diodes are connected with each other by way of a choke coil, one end of said choke coil being connected to the high terminal of the input signal source and the other end being connected to the low terminal of the input signal source.
Claim 5
Dependent Claim
66 words
A demodulation circuit as defined in claim 1 wherein the demodulator has a push-pull drive, and wherein the diodes are connected with the opposite ends of a transformer winding, the input signal source being connected to one of the ends of said transformer winding, and said transformer winding being provided with a center tap connected to a source of reference potential which constitutes the push-pull drive.
Claim 6
Dependent Claim
38 words
A demodulation circuit as defined in claim 4 wherein the center tap on said transformer winding is connected to a reference potential established by an additional current source and a diode and by-pass capacitor connected in parallel therewith.
Claim 7
Dependent Claim
68 words
A demodulation circuit as defined in claim 1 and which is structured to be driven from a multi-phase input signal source, said circuit including a multi-phased transformer to the phase windings of which said source is connected, concordantly poled diodes being assigned to each phase winding and wherein all of the diodes are biased in the forward direction such that the sum of the diode currents remains constant.
Claim 8
Dependent Claim
43 words
A demodulation circuit as defined in claim 6 wherein all of the transformer windings are connected to a common star point which is connected to a source of reference potential by way of a diode which is connected to an additional current source.
Claim 9
Dependent Claim
68 words
A twin demodulation circuit consisting of a first and a second demodulation circuit each as defined in claim 1 and wherein the second demodulator circuit which is complementary to the first one is provided for operation conjointly therewith, the outputs of both demodulators being interconnected with each other by way of a summing circuit, and the input signal source being connected to at least one of the demodulators.
Claim 10
Dependent Claim
18 words
A demodulation circuit as defined in claim 8 wherein the input signal source is connected to both demodulators.
Claim 11
Dependent Claim
29 words
A twin demodulation circuit as defined in claim 8 and which further includes an amplifier stage with high input impedance connected with the output of the twin demodulation circuit.
Claim 12
Dependent Claim
27 words
A demodulation circuit as defined in claim 1 and which further includes an amplifier stage with high input impedance connected with the output of the demodulation circuit.
References Cited (Backward Citations)
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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) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |