US3537019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical filter apparatus utilizing analog signal processing techniques
Assignee: Princeton Applied Research Corp
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Filing: 1966-11-14
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Granted: 1970-10-27
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Expires: 1986-11-14
Abstract
No abstract record available.
Inventors
- 👤 Harry S Reichard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:28
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/24; A61B5/316; A61B5/369; A61B5/377; A61B5/72; A61B5/7225; H; H03; H03H; H03H19/00; H03H19/002
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3087487A
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US3234472A
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US3154747A
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US3229212A
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US3344262A
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US3412338A
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US3445685A
Cited
US3390377A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-10-26 | 1974-04-27 | 1974-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-10-26 | 1978-04-27 | 1978-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-10-26 | 1982-04-27 | 1982-10-27 | $7700.00 | Window Closed / Lapsed |