US3868606A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Q-multiplied crystal resonator for improved hf and vhf source stabilization
Assignee: Westinghouse Electric Corp
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Filing: 1973-09-28
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Granted: 1975-02-25
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Expires: 1993-09-28
Abstract
Abstract A Q-multiplied crystal resonator is used for improved HF and VHF source stabilization utilizing a low noise controlled negative resistance generator and amplifier in combination with a crystal unit to achieve effective multiplication of the unloaded crystal Q by factors of three and more. By loading the crystal unit with the negative resistance generator a higher Q is achieved thereby improving frequency selectivity of the network. The combination of cascode connected amplifier stage, crystal, and negative resistance generator, when incorporated in the frequency discriminator portion of an AFC signal generator, provide a spectrally pure and low noise output.
Inventors
- 👤 Michael M Driscoll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:43
CPC Classifications
H; H03; H03L; H03L7/00; H03L7/02; H03B; H03B2200/00; H03B2200/0002; H03B2200/0012
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
134 words
A Q-multiplied crystal resonator circuit for improved frequency signal generator stabilization having RF input and output means comprising: a. first and second amplifier means, each having a plurality of terminals, said first and second amplifier means being in series connected configuration such that a first terminal of said second amplifier means is coupled to a first terminal of said first amplifier means, said first amplifier being adapted to receive an RF signal from said input means, said second amplifier being adapted to translate an RF signal to said output means; b. a resonant circuit including a crystal unit coupled to a second terminal of said first amplifier means, and c. active means coupled to said resonant circuit for providing positive feedback to said crystal unit thereby increasing the effective Q of said crystal unit.
Claim 2
Dependent Claim
134 words
A Q-multiplied crystal resonator circuit for improved frequency signal generator stabilization having RF input and output means comprising: a. first and second amplifier means, each having a plurality of terminals, said first and second amplifier means being in series connected configuration such that a first terminal of said second amplifier means is coupled to a first terminal of said first amplifier means, said first amplifier being adapted to receive an RF signal from said input means, said second amplifier being adapted to translate an RF signal to said output means; b. a resonant circuit including a crystal unit coupled to a second terminal of said first amplifier means, and c. active means coupled to said resonant circuit for providing positive feedback to said crystal unit thereby increasing the effective Q of said crystal unit.
Claim 3
Dependent Claim
20 words
A Q-multiplied crystal resonator circuit as set forth in claim 1 wherein said active means is a negative resistance generator.
Claim 4
Dependent Claim
64 words
A Q-multiplied crystal resonator circuit as set forth in claim 2 wherein said negative resistance generator includes amplifier means having first, second and third terminals and first, second and third impedances connected across said first and second terminals of said amplifier means in a pi network said third terminal being coupled to said resonant circuit thereby presenting a negative resistance to said crystal unit.
Claim 5
Dependent Claim
22 words
Q-multiplied crystal resonator circuit as set forth in claim 1 wherein said first and second amplifier means are cascode connected semiconductor devices.
Claim 6
Dependent Claim
28 words
A Q-multiplied crystal resonator circuit as set forth in claim 1 wherein said resonant circuit further includes circuit means to neutralize the static capacitance of said crystal unit.
Claim 7
Dependent Claim
118 words
A Q-multiplied crystal resonator circuit for improved frequency stability having RF input and output means comprising: a. a resonant circuit including a crystal unit, b. amplifier means having high Gain and isolation characteristics coupled to said crystal unit for amplifying an RF signal with high output power to crystal dissipation ratio, said amplifier means being adapted to receive an RF signal from said input means and said amplifier means being adapted to translate an RF signal to said output means; and c. active negative resistance generator means coupled to said resonant circuit for providing positive feedback to said crystal unit thereby increasing the Q of said resonant circuit for improved frequency selectivity and suppression of amplifier means noise.
Claim 8
Dependent Claim
118 words
A Q-multiplied crystal resonator circuit for improved frequency stability having RF input and output means comprising: a. a resonant circuit including a crystal unit, b. amplifier means having high Gain and isolation characteristics coupled to said crystal unit for amplifying an RF signal with high output power to crystal dissipation ratio, said amplifier means being adapted to receive an RF signal from said input means and said amplifier means being adapted to translate an RF signal to said output means; and c. active negative resistance generator means coupled to said resonant circuit for providing positive feedback to said crystal unit thereby increasing the Q of said resonant circuit for improved frequency selectivity and suppression of amplifier means noise.
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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) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |