US3634700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Bidirectional frequency scan system
Assignee: RCA Licensing Corp
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Filing: 1970-12-29
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Granted: 1972-01-11
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Expires: 1990-12-29
Abstract
Abstract A bidirectional frequency scan system in which a variable scan control voltage across a variable tuning reactance in the tuning circuitry is determined by the charge on a scan capacitor. Means are provided for selectively increasing or decreasing the charge on the scan capacitor so that when the capacitor is charging the system scans in one direction, and when the capacitor is discharging the system scans in the opposite direction.
Inventors
- 👤 Joseph A Worcester
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:07
CPC Classifications
H; H03; H03J; H03J7/00; H03J7/18; H03J7/20; H03J7/24; H03J7/26
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
127 words
A bidirectional frequency scan system for selectively scanning through a frequency band in one of two directions and stopping when a received signal having an amplitude above a predetermined level is encountered, comprising: a. storage means for developing a bidirectional scan control voltage, b. variable conduction means for increasing the voltage of said storage means to provide scanning in one direction, and for decreasing the voltage of said storage means to provide scanning in the opposite direction, and c. control means responsive to said received signal for controlling the operation of said variable conduction means so as to provide scanning in either of said two directions and for fixing the level of said scan control voltage upon the amplitude of said received signal exceeding said predetermined level.
Claim 2
Dependent Claim
127 words
A bidirectional frequency scan system for selectively scanning through a frequency band in one of two directions and stopping when a received signal having an amplitude above a predetermined level is encountered, comprising: a. storage means for developing a bidirectional scan control voltage, b. variable conduction means for increasing the voltage of said storage means to provide scanning in one direction, and for decreasing the voltage of said storage means to provide scanning in the opposite direction, and c. control means responsive to said received signal for controlling the operation of said variable conduction means so as to provide scanning in either of said two directions and for fixing the level of said scan control voltage upon the amplitude of said received signal exceeding said predetermined level.
Claim 3
Dependent Claim
56 words
A scan system as in claim 1 wherein said control means includes: a. bias voltage means, b. circuit means responsive to the amplitude of the received signal and to the direction of the scan, and c. means for applying the combined outputs from said bias voltage means and said circuit means to said variable conduction means.
Claim 4
Dependent Claim
66 words
A scan system as in claim 2 wherein said storage means includes a first capacitor and said variable conduction means comprises: a. a voltage source coupled in series with said capacitor for providing charge thereto, and b. a control transistor coupled in parallel with said capacitor, the conduction of said transistor being responsive to said control means for regulating the amount of charge on said capacitor.
Claim 5
Dependent Claim
78 words
A scan system as in claim 3 wherein said bias voltage means comprises: a. a second capacitor, and b. switching means for selectively coupling first and second voltage levels across said second capacitor, said first voltage level having a value for inhibiting conduction of said transistor so as to permit said first capacitor to charge, said second voltage level having a value for producing high conduction of said transistor so as to permit said first capacitor to discharge.
Claim 6
Dependent Claim
58 words
A scan system as in claim 4 wherein said circuit means includes a discriminator for generating a bipolar output, one polarity of said output combining with said first voltage level to establish an equilibrium condition within said variable conduction means, and the other polarity of said output combining with said second voltage level to establish said equilibrium condition.
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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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |