EP0009293A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Circuit for connecting, at one time, only one of a number of telephone sets to a subscriber's line
Assignee: Staat der Nederlanden (Staatsbedrijf der Posterijen Telegrafie en Telefonie)
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Filing: 1979-09-20
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Granted: —
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Expires: 1999-09-20
Abstract
Abstract Circuit which can be incorporated in a telephone set or the like to prevent that more than. one of a number of telephone sets, which are multiple-connected to a subscriber's line, get into the conversation or signalling state. The circuit comprises a supply circuit, such as a rectifier bridge circuit, switching means for switching through the telephone set to the subscriber's line and a control circuitfor controlling the switching means. To keep the voltage drop across the circuit as small as possible the switching means (9) can be incorporated in the supply circuit.
Inventors
- 👤 Johannes De Bode
- 👤 Arie De Lange
- 👤 Wilhelmus Antonius Van Leeuwen
- 👤 Hendrik Van Noort
- 👤 Andries Adrianus De Raad
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 10:04
CPC Classifications
H; H04; H04Q; H04Q5/00; H04Q5/02; H04M; H04M1/00; H04M1/68; H04M1/70
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
102 words
Circuit allowing only one of a number of telephone sets, which are multiple-connected to a subscriber's line, to get, at one time, into the conversation or signalling state, and comprising in each of the telephone sets: - a supply circuit for the equipment in the telephone set or coupled to it; - switching means for switching the equipment that follows into the conversation or signalling state, and - a control circuit for controlling the switching means dependent on the voltage across the subscriber's line, characterized in that the supply circuit and the switching means have at least one semiconductor element in common.
References Cited (Backward Citations)
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