Patent US2362353A successfully refreshed from Google Patents.
US3723906A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Uhf oscillator
Assignee: Zenith Electronics LLC
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Filing: 1971-02-26
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Granted: 1973-03-27
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Expires: 1991-02-26
Abstract
Abstract A UHF transistor oscillator for a television tuner employs a voltage dependent variable capacitance (varactor) element in the feedback circuit coupled between the output and input circuits of the transistor. An adjustable control circuit, which connects the varactor to a source of D.C. potential, serves to vary the capacitance exhibited by varactor in the feedback circuit while simultaneously changing the reactive contribution of the varactor to the transistor input circuit.
Inventors
- 👤 A Pedersen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:25
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/18; H03B5/08; H03B5/12; H03B5/1203; H03B5/1231; H03B5/1237; H03B5/124; H03B5/1243
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
235 words
An oscillator tunable across a predetermined frequency range comprising: a transistor having first, second and third electrodes; an input circuit coupled between said first and second electrodes; an output circuit coupled between said second and third electrodes and comprising a resonant circuit having adjustable tuning means and including an inductance element and a capacitance element, at least one of said elements being adjustable in response to actuation of said tuning means for tuning said resonant circuit to a desired frequency in said oscillator range; a feedback circuit comprising a single capacitive coupling element consisting of a voltage-dependent capacitor coupled between said output circuit and said input circuit; a first source of unidirectional potential; a second source of unidirectional potential having a polarity opposite that of said first source; and a control circuit connecting one terminal of said voltage dependent feedback capacitor to a terminus of a given polarity of said first source of unidirectional potential and for connecting the other terminal of said voltage dependent feedback capacitor to a terminus of said second source having a polarity opposite that of said given polarity, said control circuit being response to actuation of said tuning means, for varying the capacitance exhibited by said voltage dependent capacitor in said feedback circuit while simultaneously changing the reactive contribution of said voltage dependent feedback capacitor to said input circuit as said resonant circuit is tuned across said oscillator frequency range.
Claim 2
Dependent Claim
235 words
An oscillator tunable across a predetermined frequency range comprising: a transistor having first, second and third electrodes; an input circuit coupled between said first and second electrodes; an output circuit coupled between said second and third electrodes and comprising a resonant circuit having adjustable tuning means and including an inductance element and a capacitance element, at least one of said elements being adjustable in response to actuation of said tuning means for tuning said resonant circuit to a desired frequency in said oscillator range; a feedback circuit comprising a single capacitive coupling element consisting of a voltage-dependent capacitor coupled between said output circuit and said input circuit; a first source of unidirectional potential; a second source of unidirectional potential having a polarity opposite that of said first source; and a control circuit connecting one terminal of said voltage dependent feedback capacitor to a terminus of a given polarity of said first source of unidirectional potential and for connecting the other terminal of said voltage dependent feedback capacitor to a terminus of said second source having a polarity opposite that of said given polarity, said control circuit being response to actuation of said tuning means, for varying the capacitance exhibited by said voltage dependent capacitor in said feedback circuit while simultaneously changing the reactive contribution of said voltage dependent feedback capacitor to said input circuit as said resonant circuit is tuned across said oscillator frequency range.
Claim 3
Dependent Claim
27 words
A tunable oscillator as set forth in claim 1 in which said first, second and third electrodes of said transistor comprise emitter, base and collector electrodes, respectively.
Claim 4
Dependent Claim
62 words
A tunable oscillator as set forth in claim 1 in which said adjustable element in said tunable resonant circuit comprises a voltage dependent capacitor, and in which said tuning voltage dependent capacitor is connected across said first source of potential and said feedback voltage dependent capacitor is connected across a series-opposing arrangement of said first potential source and said second potential source.
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) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |