Patent US2820903A successfully refreshed from Google Patents.
US2820903A
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US
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Wien bridge oscillator
Assignee: Allard Way Holdings Ltd
•
Filing: 1955-04-06
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Granted: 1958-01-21
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Expires: 1975-04-06
Abstract
No abstract record available.
Inventors
- 👤 Roulston Kenneth Irwin
- 👤 Pizzey Cyril Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:30
CPC Classifications
F; F02; F02C; F02C7/00; F02C7/22; F02C7/232; F02C7/228; H; H03; H03B; H03B5/00; H03B5/20; H03B5/26; H03B5/28; H03H; H03H11/00; H03H11/02; H03H11/16; H03H11/18; F05; F05D; F05D2270/00; F05D2270/30; F05D2270/31
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2444084A
Cited
GB644083A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-01-20 | 1961-07-22 | 1962-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-01-20 | 1965-07-22 | 1966-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-01-20 | 1969-07-22 | 1970-01-21 | $7700.00 | Window Closed / Lapsed |