Patent US3708762A successfully refreshed from Google Patents.
US3708762A
Expired / Lapsed
US
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Electronic oscillator using r-c filter in which frequency is controlled by one resistor
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1971-04-29
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Granted: 1973-01-02
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Expires: 1991-04-29
Abstract
Abstract An electric oscillator includes a source of electrical energy coupled to a frequency determining network. The network includes first and second branches connected in parallel wherein the first branch comprises a capacitor and the second branch comprises a variable resistor connected to one end of each of two fixed resistors whose other ends are interconnected by a further capacitor.
Inventors
- 👤 L Nilsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 08:04
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/20; H03B5/24; H03B2200/00; H03B2200/006; H03B2200/0066; H03B2201/00; H03B2201/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
134 words
A variable frequency oscillator comprising a source of electrical energy, a two-terminal frequency determining circuit, means for connecting the source of electrical energy to at least one terminal of said frequency determining circuit, means for applying a reference potential to the other terminal of said frequency determining circuit, said circuit comprising two branches connected across the two terminals, one of said branches including a first capacitor, the other of said branches including a controllably variable resistance element having one end connected to one of said terminals, first and second resistors each having one end connected to the other end of said controllably variable resistance element, a second capacitor connecting the ends of said resistors, and means for connecting said other end of at least one of said resistors to the other of said terminAls.
Claim 2
Dependent Claim
134 words
A variable frequency oscillator comprising a source of electrical energy, a two-terminal frequency determining circuit, means for connecting the source of electrical energy to at least one terminal of said frequency determining circuit, means for applying a reference potential to the other terminal of said frequency determining circuit, said circuit comprising two branches connected across the two terminals, one of said branches including a first capacitor, the other of said branches including a controllably variable resistance element having one end connected to one of said terminals, first and second resistors each having one end connected to the other end of said controllably variable resistance element, a second capacitor connecting the ends of said resistors, and means for connecting said other end of at least one of said resistors to the other of said terminAls.
Claim 3
Dependent Claim
18 words
The variable frequency oscillator of claim 1 wherein said controllably variable resistance element includes a field effect transistor.
Claim 4
Dependent Claim
47 words
The variable frequency oscillator of claim 2 wherein the field effect transistor has two main electrodes connected respectively to the two ends of said controllably variable resistance element and has a control electrode for receiving a control signal for varying the resistance between said two main electrodes.
References Cited (Backward Citations)
US2583649A
Cited
US3555448A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-02 | 1976-07-03 | 1977-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-02 | 1980-07-03 | 1981-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-02 | 1984-07-03 | 1985-01-02 | $7700.00 | Window Closed / Lapsed |