FR812772A - Improvements to telephone systems - Google Patents

Improvements to telephone systems

Info

Publication number
FR812772A
FR812772A FR812772DA FR812772A FR 812772 A FR812772 A FR 812772A FR 812772D A FR812772D A FR 812772DA FR 812772 A FR812772 A FR 812772A
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.)
Telefonaktiebolaget LM Ericsson AB
Original Assignee
Telefonaktiebolaget LM Ericsson AB
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 Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Application granted granted Critical
Publication of FR812772A publication Critical patent/FR812772A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/442—Signalling arrangements; Manipulation of signalling currents using alternate current with out-of-voice band signalling frequencies
    • H04Q1/4423—Signalling arrangements; Manipulation of signalling currents using alternate current with out-of-voice band signalling frequencies using one signalling frequency

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Devices For Supply Of Signal Current (AREA)
FR812772D 1935-11-04 1936-10-29 Improvements to telephone systems Expired FR812772A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE465655X 1935-11-04

Publications (1)

Publication Number Publication Date
FR812772A true FR812772A (en) 1937-05-18

Family

ID=20310269

Family Applications (1)

Application Number Title Priority Date Filing Date
FR812772D Expired FR812772A (en) 1935-11-04 1936-10-29 Improvements to telephone systems

Country Status (2)

Country Link
FR (1) FR812772A (en)
GB (1) GB465655A (en)

Also Published As

Publication number Publication date
GB465655A (en) 1937-05-11

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