Patent US126997A successfully refreshed from Google Patents.
Patent US3899753A successfully refreshed from Google Patents.
US3899753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled high frequency transistor crystal oscillator
Assignee: International Business Machines Corp
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Filing: 1974-05-06
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Granted: 1975-08-12
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Expires: 1994-05-06
Abstract
Abstract A series-resonant crystal provides ac emitter coupling for a current switch whose output is fed back to its input to sustain oscillations at the resonant frequency of the crystal. A mixer circuit is provided so that the feedback is positive for small signal amplitudes whereby oscillations build up spontaneously when the circuit is switched on and then controls the feedback automatically so that it becomes negative for large signal amplitudes. This limits the output without resort to device saturation or cut-off, both of which adversely affect the speed, and as such, limit the high frequency performance of the oscillator.
Inventors
- 👤 Shashi D Malaviya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:34
CPC Classifications
H; H03; H03K; H03K3/00; H03K3/02; H03K3/26; H03K3/28; H03K3/281; H03K3/282; H03K3/283
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
74 words
A controlled amplitude oscillator comprising: a. collector-to-base cross-coupled first and second transistors; b. a piezoelectric crystal connected between the emitters of said first and second transistors; and c. a mixer circuit connected between the bases of said first and second transistors, wherein said mixer circuit comprises d. two like resistors connected in series between said bases; and e. a third resistor connected from the common junction of said like resistors to a reference potential.
Claim 2
Dependent Claim
74 words
A controlled amplitude oscillator comprising: a. collector-to-base cross-coupled first and second transistors; b. a piezoelectric crystal connected between the emitters of said first and second transistors; and c. a mixer circuit connected between the bases of said first and second transistors, wherein said mixer circuit comprises d. two like resistors connected in series between said bases; and e. a third resistor connected from the common junction of said like resistors to a reference potential.
Claim 3
Dependent Claim
17 words
the oscillator of claim 1 wherein said third resistor has a higher resistance than said like resistors.
Claim 4
Dependent Claim
73 words
A controlled amplitude oscillator comprising: a. collector-to-base cross-coupled first and second transistors; b. a piezoelectric crystal connected between the emitters of said first and second transistors; and c. a mixer circuit connected between the bases of said first and second transistors including an emitter follower-transistor in each arm in the cross-coupling network between the collector output of one of said first and second transistors and the base of the other of said transistors.
Claim 5
Dependent Claim
73 words
A controlled amplitude oscillator comprising: a. collector-to-base cross-coupled first and second transistors; b. a piezoelectric crystal connected between the emitters of said first and second transistors; and c. a mixer circuit connected between the bases of said first and second transistors including an emitter follower-transistor in each arm in the cross-coupling network between the collector output of one of said first and second transistors and the base of the other of said transistors.
Claim 6
Dependent Claim
38 words
The oscillator of claim 3 wherein said mixer circuit comprises a. two like resistors connected in series between said bases, and b. a third resistor connected from the common junction of said like resistors to a reference potential.
Claim 7
Dependent Claim
17 words
The oscillator of claim 4 wherein said third resistor has a higher resistance than said like resistors.
References Cited (Backward Citations)
US3824491A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |