DE2201764B2
Expired / Lapsed
DE
⏱️ 0.0 years remaining
Circuit arrangement for converting an electrical call signal into an acoustic call signal in telecommunication systems, in particular tone alarm clocks
Assignee: AT&T Inc
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Filing: 1972-01-14
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Granted: —
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Expires: 1992-01-14
Abstract
No abstract record available.
Inventors
- 👤 Robert Francis Lincroft Mcalonie
- 👤 Helmuth Otto Middletown Sautter
- 👤 David Carlaw Holmdel Trimble
Bibliographic Details
Application Number
—
Jurisdiction
DE
Data Source
google_patents
Last Synchronized
2026-10-24 10:07
CPC Classifications
H; H04; H04M; H04M19/00; H04M19/02; H04M19/04; Y; Y02; Y02D; Y02D30/00; Y02D30/70
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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