FR856679A - Electrical communications system - Google Patents

Electrical communications system

Info

Publication number: FR856679A
Authority: FR; France
Prior art keywords: communications system; electrical communications; electrical; communications
Prior art date: 1938-06-21
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

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.)

1938-06-21

Filing date

1939-06-20

Publication date

1940-08-01

1939-06-20 Application filed by Le Materiel Telephonique Thomson CSF filed Critical Le Materiel Telephonique Thomson CSF

1940-08-01 Application granted granted Critical

1940-08-01 Publication of FR856679A publication Critical patent/FR856679A/en

Status Expired legal-status Critical Current

Classifications

- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/40—Monitoring; Testing of relay systems
- H04B17/401—Monitoring; Testing of relay systems with selective localization
- H04B17/402—Monitoring; Testing of relay systems with selective localization using different frequencies
- H04B17/404—Monitoring; Testing of relay systems with selective localization using different frequencies selected by local filters

Landscapes

Physics & Mathematics (AREA)
Electromagnetism (AREA)
Engineering & Computer Science (AREA)
Computer Networks & Wireless Communication (AREA)
Signal Processing (AREA)

FR856679D 1938-06-21 1939-06-20 Electrical communications system Expired FR856679A (en)

Applications Claiming Priority (1)

Application Number	Priority Date	Filing Date	Title
GB856679X		1938-06-21

Publications (1)

Publication Number	Publication Date
FR856679A true FR856679A (en)	1940-08-01

Family

ID=10590604

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
FR856679D Expired FR856679A (en)	1938-06-21	1939-06-20	Electrical communications system

Country Status (1)

Country	Link
FR (1)	FR856679A (en)

1939
- 1939-06-20 FR FR856679D patent/FR856679A/en not_active Expired

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