FR840325A - Improvements to telephone systems - Google Patents

Improvements to telephone systems

Info

Publication number
FR840325A
FR840325A FR840325DA FR840325A FR 840325 A FR840325 A FR 840325A FR 840325D A FR840325D A FR 840325DA FR 840325 A FR840325 A FR 840325A
Authority
FR
France
Prior art keywords
telephone systems
telephone
systems
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
Other languages
French (fr)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Associated Electric Laboratories Inc
Original Assignee
Associated Electric Laboratories Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Associated Electric Laboratories Inc filed Critical Associated Electric Laboratories Inc
Application granted granted Critical
Publication of FR840325A publication Critical patent/FR840325A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/08—Indicating faults in circuits or apparatus
    • H04M3/12—Marking faulty circuits "busy"; Enabling equipment to disengage itself from faulty circuits ; Using redundant circuits; Response of a circuit, apparatus or system to an error
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M15/00—Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP
    • H04M15/38—Charging, billing or metering by apparatus other than mechanical step-by-step counter type

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Mobile Radio Communication Systems (AREA)
FR840325D 1937-07-08 1938-07-06 Improvements to telephone systems Expired FR840325A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US152497A US2216528A (en) 1937-07-08 1937-07-08 Telephone system

Publications (1)

Publication Number Publication Date
FR840325A true FR840325A (en) 1939-04-24

Family

ID=22543180

Family Applications (1)

Application Number Title Priority Date Filing Date
FR840325D Expired FR840325A (en) 1937-07-08 1938-07-06 Improvements to telephone systems

Country Status (2)

Country Link
US (1) US2216528A (en)
FR (1) FR840325A (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2817573A (en) * 1952-10-31 1957-12-24 Ericsson Telefon Ab L M Time-marking device for charging telephone calls
US3390395A (en) * 1966-05-31 1968-06-25 Commac Inc Elapsed time recording device and method
US3962548A (en) * 1973-11-07 1976-06-08 Stone Jr Wayne B Direct readout exhibitor for determining long distance telephone charges

Also Published As

Publication number Publication date
US2216528A (en) 1940-10-01

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