FR452222A
Expired / Lapsed
FR
⏱️ 0.0 years remaining
Improvement of telephone speech transmission
Assignee: PIERRE-EMMANUEL-EMILE RAVEROT
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Filing: 1912-12-20
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Granted: 1913-05-10
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Expires: 1932-12-20
Abstract
No abstract record available.
Inventors
- 👤 Pierre-Emmanuel-Emile Raverot
Bibliographic Details
Application Number
—
Jurisdiction
FR
Data Source
google_patents
Last Synchronized
2026-11-09 03:40
CPC Classifications
H; H04; H04R; H04R13/00
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References Cited (Backward Citations)
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