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DE557433C
Expired / Lapsed
DE
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Process for the generation of loud and purely sinusoidal tones from the interference of electrical basic vibrations, especially for testing human hearing acuity
Assignee: FRITZ KRAFFT DIPL ING
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Filing: 1926-09-19
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Granted: 1932-08-23
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Expires: 1946-09-19
Abstract
No abstract record available.
Inventors
- 👤 Dr Wolfgang Schwarz
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-11-03 13:59
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/12
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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