US3792359A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High frequency automatic gain control circuits
Assignee: RCA Licensing Corp
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Filing: 1971-04-14
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Granted: 1974-02-12
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Expires: 1991-04-14
Abstract
Abstract A common base amplifier used for high frequency amplification has an automatic gain control voltage applied thereto to vary the gain in a reverse mode. As the gain of the transistor is decreased, a unilateral current conduction device, coupled to the emitter electrode or input of the amplifier, is caused to conduct. The conduction of the unilateral device causes the voltages between the electrodes of the amplifier to remain constant, while further causing additional impedance shunting of the transistor to maintain the input impedance of the amplifier relatively constant during AGC operation.
Inventors
- 👤 D Carlson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:00
CPC Classifications
H; H03; H03G; H03G3/00; H03G3/20; H03G3/30; H03G3/3052
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
149 words
An amplifier comprising: a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode and an output circuit coupled to said collector electrode, said input circuit including a resistive element connected between said emitter electrode and a point of reference potential, a unilateral conducting device having a first terminal direct coupled to said emitter electrode of said transistor, means coupling a second terminal of said unilateral conducting device to said point of reference potential at signal frequencies, an automatic gain controlling direct current bias source, and means connecting said source of gain controlling direct current bias to said second terminal of said unilateral conducting device to cause the emitter current of said transistor to decrease and the unilateral conducting device current to increase with increases in automatic gain controlling direct current bias.
Claim 2
Dependent Claim
149 words
An amplifier comprising: a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode and an output circuit coupled to said collector electrode, said input circuit including a resistive element connected between said emitter electrode and a point of reference potential, a unilateral conducting device having a first terminal direct coupled to said emitter electrode of said transistor, means coupling a second terminal of said unilateral conducting device to said point of reference potential at signal frequencies, an automatic gain controlling direct current bias source, and means connecting said source of gain controlling direct current bias to said second terminal of said unilateral conducting device to cause the emitter current of said transistor to decrease and the unilateral conducting device current to increase with increases in automatic gain controlling direct current bias.
Claim 3
Dependent Claim
152 words
An amplifier comprising: a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode anD an output circuit coupled to said collector electrode, said input circuit including a resistive element connected between said emitter electrode and a point of reference potential, a unilateral conducting device having a first terminal direct coupled to said emitter electrode of said transistor, means coupling said second terminal of said unilateral conducting device to said point of reference potential at signal frequencies includes a capacitor having low impedance to signal frequencies, an automatic gain controlling bias source, and means connecting said source of gain controlling bias to said second terminal of said unilateral conducting device to cause the emitter current of said transistor to decrease and the unilateral conducting device current to increase with increases in automatic gain controlling bias.
Claim 4
Dependent Claim
152 words
An amplifier comprising: a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode anD an output circuit coupled to said collector electrode, said input circuit including a resistive element connected between said emitter electrode and a point of reference potential, a unilateral conducting device having a first terminal direct coupled to said emitter electrode of said transistor, means coupling said second terminal of said unilateral conducting device to said point of reference potential at signal frequencies includes a capacitor having low impedance to signal frequencies, an automatic gain controlling bias source, and means connecting said source of gain controlling bias to said second terminal of said unilateral conducting device to cause the emitter current of said transistor to decrease and the unilateral conducting device current to increase with increases in automatic gain controlling bias.
Claim 5
Dependent Claim
34 words
An amplifier as defined in claim 2 wherein said unilateral conducting device is poled to provide direct current through said resistive element in the same direction as the direct current from said emitter electrode.
Claim 6
Dependent Claim
24 words
An amplifier as defined in claim 2 wherein said input circuit is coupled to the mixer circuit of an ultra high frequency television tuner.
Claim 7
Dependent Claim
113 words
An amplifier comprising, a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode and an output circuit coupled to said collector electrode, said signal input circuit including a resistive element connected between said emitter electrode and a point of reference potential, means providing a source of gain controlling direct current bias, unilateral conducting means connecting said source of gain controlling direct current bias to said emitter electrode and said resistive element, said unilateral conducting means poled to provide direct current through said resistive element in the same direction as direct current from said emitter electrode.
Claim 8
Dependent Claim
113 words
An amplifier comprising, a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode and an output circuit coupled to said collector electrode, said signal input circuit including a resistive element connected between said emitter electrode and a point of reference potential, means providing a source of gain controlling direct current bias, unilateral conducting means connecting said source of gain controlling direct current bias to said emitter electrode and said resistive element, said unilateral conducting means poled to provide direct current through said resistive element in the same direction as direct current from said emitter electrode.
Claim 9
Dependent Claim
29 words
An amplifier as defined in claim 5 including means for biasing said unilateral conducting means to a condition of minimum conduction when said transistor is biased for maximum gain.
Claim 10
Dependent Claim
23 words
An amplifier as defined in claim 5 wherein said signal input circuit is coupled to a mixer circuit of a UHF television tuner.
Claim 11
Dependent Claim
138 words
An amplifier comprising, a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode and an output circuit coupled to said collector electrode, said signal input circuit including a resistive element connected between said emitter electrode and a point of reference potential, means providing a source of gain controlling bias, unilateral conducting means connecting said source of gain controlling bias to said emitter electrode and said resistive element, said unilateral conducting means poled to provide direct current through said resistive element in the same direction as direct current from said emitter electrode, and a capacitor exhibiting low impedance to signal frequencies connected between the electrode of said unilateral conducting means remote from said emitter electrode and said point of reference potential.
Claim 12
Dependent Claim
138 words
An amplifier comprising, a transistor having base, emitter and collector electrodes, means connecting said transistor in a common base amplifier configuration including a signal input circuit coupled to said emitter electrode and an output circuit coupled to said collector electrode, said signal input circuit including a resistive element connected between said emitter electrode and a point of reference potential, means providing a source of gain controlling bias, unilateral conducting means connecting said source of gain controlling bias to said emitter electrode and said resistive element, said unilateral conducting means poled to provide direct current through said resistive element in the same direction as direct current from said emitter electrode, and a capacitor exhibiting low impedance to signal frequencies connected between the electrode of said unilateral conducting means remote from said emitter electrode and said point of reference potential.
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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) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |