Patent US3564129A successfully refreshed from Google Patents.
US3564129A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Noise limiting circuit using switched filter
Assignee: Rank Cintel Ltd
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Filing: 1967-12-08
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Granted: 1971-02-16
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Expires: 1987-12-08
Abstract
Abstract An electrical noise limiting circuit for use in an apparatus producing a composite signal including an information carrying signal of a selected bandwidth including a train of recurrent pulses. The circuit includes a switch responsive to the pulses in the composite signal, and a filter selectively connected to the apparatus by the switch. The filter reduces the level of the noise component in the composite signal at least during the periods of one or more of the pulses.
Inventors
- 👤 Peter William Blaxtan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:48
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/16; H04N5/21
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
128 words
An electric noise limiting circuit arrangement for use in apparatus producing a composite signal comprising an informationcarrying signal of selected bandwidth and a train of recurrent pulses, comprising: switching means having a control terminal connected to receive only said train of recurrent pulses, said switching means operating only in first or second alternative conditions and being responsive to initial transition of a said pulse to switch from said first to said second condition and responsive to terminal transition of a said pulse to switch back to said first condition, and filter means brought into operative connection by the switching means only for the duration of said second condition and effective to reduce the level of noise component in the composite signal during each pulse of said recurrent train.
Claim 2
Dependent Claim
128 words
An electric noise limiting circuit arrangement for use in apparatus producing a composite signal comprising an informationcarrying signal of selected bandwidth and a train of recurrent pulses, comprising: switching means having a control terminal connected to receive only said train of recurrent pulses, said switching means operating only in first or second alternative conditions and being responsive to initial transition of a said pulse to switch from said first to said second condition and responsive to terminal transition of a said pulse to switch back to said first condition, and filter means brought into operative connection by the switching means only for the duration of said second condition and effective to reduce the level of noise component in the composite signal during each pulse of said recurrent train.
Claim 3
Dependent Claim
22 words
A circuit arrangement as claimed in claim 1, wherein the filter means are effective to reduce the bandwidth of the composite signal.
Claim 4
Dependent Claim
23 words
A circuit arrangement as claimed in claim 1, wherein the composite signal is a television video signal and the pulses are blanking pulses.
Claim 5
Dependent Claim
22 words
A circuit arrangement as claimed in claim 3 wherein the filter means are arranged to reduce the bandwidth of the video signal.
Claim 6
Dependent Claim
21 words
A circuit arrangement as claimed in claim 4 wherein the filter means are connected in series relation with the video signal.
Claim 7
Dependent Claim
21 words
A circuit arrangement as claimed in claim 4, wherein the filter means are connected in shunt relation with the video signal.
Claim 8
Dependent Claim
15 words
A circuit arrangement as claimed in claim 6, wherein the filter means comprise a capacitor.
Claim 9
Dependent Claim
16 words
A circuit arrangement as claimed in claim 1, wherein the switch means are electronic switch means.
Claim 10
Dependent Claim
35 words
A circuit arrangement as claimed in claim 8, wherein the electronic switch means comprises two switches respectively providing two circuit paths from a common input and providing a common output from the two circuit paths.
Claim 11
Dependent Claim
20 words
A circuit arrangement as claimed in claim 9, wherein the filter means are inserted in one of the circuit paths.
Claim 12
Dependent Claim
28 words
A circuit arrangement as claimed in claim 8, wherein the electronic switch means is a single switch and selectively provides a single shunt path to the video signal.
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) | 1974-02-15 | 1974-08-17 | 1975-02-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-15 | 1978-08-17 | 1979-02-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-15 | 1982-08-17 | 1983-02-16 | $7700.00 | Window Closed / Lapsed |