FR664197A - Improvements to telephone systems - Google Patents

Improvements to telephone systems

Info

Publication number
FR664197A
FR664197A FR664197DA FR664197A FR 664197 A FR664197 A FR 664197A FR 664197D A FR664197D A FR 664197DA FR 664197 A FR664197 A FR 664197A
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.)
Thales SA
Original Assignee
Le Materiel Telephonique Thomson CSF
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 Le Materiel Telephonique Thomson CSF filed Critical Le Materiel Telephonique Thomson CSF
Application granted granted Critical
Publication of FR664197A publication Critical patent/FR664197A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/20—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
FR664197D 1928-11-20 1928-11-20 Improvements to telephone systems Expired FR664197A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR664197T 1928-11-20

Publications (1)

Publication Number Publication Date
FR664197A true FR664197A (en) 1929-08-30

Family

ID=9012509

Family Applications (1)

Application Number Title Priority Date Filing Date
FR664197D Expired FR664197A (en) 1928-11-20 1928-11-20 Improvements to telephone systems

Country Status (1)

Country Link
FR (1) FR664197A (en)

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