US3555299A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined video signal limiter
Assignee: Rank Cintel Ltd
•
Filing: 1968-01-02
•
Granted: 1971-01-12
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Expires: 1988-01-02
Abstract
Abstract An electrical signal is limited to the range between first and second levels by limiting the signal to a direct current at the first level and limiting the resulting signal relative to a second direct current representing the difference between the first and second levels.
Inventors
- 👤 John David Millward
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:06
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/14; H04N5/16
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
171 words
A circuit arrangement for limiting an electrical signal to a range between first and second levels, comprising: a source of first constant direct current representative of the first level; a first circuit portion connected to receive said first direct current and said electrical signal and effective to provide therefrom a current signal representative of the difference of the first direct current and values of said electrical signal on the range side of the first level, thereby limiting said electrical signal to the first level; a source of second constant direct current representative of the difference between the first and second levels; and a further circuit portion connected to receive said second direct current and said signal from the first circuit portion and effective to provide therefrom a current signal representative of the extent to which the output of the first circuit portion is less than said second direct current, thereby providing a representation of said electrical signal that is fully limited to said range at both the first and second levels.
Claim 2
Dependent Claim
171 words
A circuit arrangement for limiting an electrical signal to a range between first and second levels, comprising: a source of first constant direct current representative of the first level; a first circuit portion connected to receive said first direct current and said electrical signal and effective to provide therefrom a current signal representative of the difference of the first direct current and values of said electrical signal on the range side of the first level, thereby limiting said electrical signal to the first level; a source of second constant direct current representative of the difference between the first and second levels; and a further circuit portion connected to receive said second direct current and said signal from the first circuit portion and effective to provide therefrom a current signal representative of the extent to which the output of the first circuit portion is less than said second direct current, thereby providing a representation of said electrical signal that is fully limited to said range at both the first and second levels.
Claim 3
Dependent Claim
53 words
A circuit arrangement as claimed in claim 1 in which the said electrical signal is a current signal and the first signal level is the lower level, whereby a partly limited signal current flows in the second circuit portion when the signal current exceeds the first direct current and thereby the first level.
Claim 4
Dependent Claim
42 words
A circuit arrangement as claimed in claim 1 including a diode element interconnecting the first circuit portion and the further circuit portion whereby the said signal limited to the first level is applied to the further circuit portion through said diode element.
Claim 5
Dependent Claim
37 words
A circuit arrangement as claimed in; claim 1 including an output line and a signal responsive element, the fully limited signal in the further circuit portion being applied to the output line through the signal responsive element.
Claim 6
Dependent Claim
17 words
A circuit arrangement as claimed in claim 4 in which said signal responsive element is a transistor.
Claim 7
Dependent Claim
29 words
A circuit arrangement as claimed in claim 1, including diodes effective to curtail voltage transients in said circuit portions when the said electrical signal passes outside the limiting levels.
Claim 8
Dependent Claim
27 words
A circuit arrangement as claimed in claim 1 in combination with means for applying a television blanking signal constituting said electrical signal to the first circuit portion.
References Cited (Backward Citations)
US2775714A
Cited
US3373366A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-11 | 1974-07-13 | 1975-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-11 | 1978-07-13 | 1979-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-11 | 1982-07-13 | 1983-01-12 | $7700.00 | Window Closed / Lapsed |