CH233108A
Expired / Lapsed
CH
⏱️ 0.0 years remaining
Aural frequency amplifier arrangement with characteristics adapted to the physiological requirements of the listener.
Assignee: Planer F E
•
Filing: 1939-03-11
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Granted: —
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Expires: 1959-03-11
Abstract
No abstract record available.
Inventors
- 👤 Planer F E
- 👤 Fenyves F L
Bibliographic Details
Application Number
—
Jurisdiction
CH
Data Source
google_patents
Last Synchronized
2026-10-30 22:15
CPC Classifications
H; H03; H03G; H03G9/00; H03G9/02; H03G9/04; H03G9/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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