Patent US2159790A successfully refreshed from Google Patents.
US2159790A
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Frequency analyzer
Assignee: Siemens and Halske AG
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Filing: 1936-08-12
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Granted: 1939-05-23
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Expires: 1956-08-12
Abstract
Abstract 471,632. Impedance networks. SIEMENS & HALSKE AKT.-GES. Aug. 12, 1936, No. 22246. Convention date, Aug. 13, 1935. [Class 40 (iii)] [Also in Group XXXVI] A filter circuit for use in apparatus for electrically analysing the frequencies of oscillations consists of two circuits containing inductance, resistance and capacity, the two circuits being coupled together by a tapping on the inductance L of the first circuit, whereby steep-sided transmission curves are obtained. The transmission curves of adjacent filters intersect at approximately 0À7 of their maximum height.
Inventors
- 👤 Freystedt Erich
- 👤 Bath Fritz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:51
CPC Classifications
G; G10; G10L; G10L21/00; G10L21/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-05-22 | 1942-11-21 | 1943-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-05-22 | 1946-11-21 | 1947-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-05-22 | 1950-11-21 | 1951-05-23 | $7700.00 | Window Closed / Lapsed |