Patent DE452286C successfully refreshed from Google Patents.
DE452286C
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Pupin guidance for speech transmission over long distances
Assignee: Siemens and Halske AG
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Filing: 1923-10-05
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Granted: 1927-11-11
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Expires: 1943-10-05
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-29 09:28
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H04B3/146; H04B3/147
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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