GB155823A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB155823A
GB155823A GB34809/20A GB3480920A GB155823A GB 155823 A GB155823 A GB 155823A GB 34809/20 A GB34809/20 A GB 34809/20A GB 3480920 A GB3480920 A GB 3480920A GB 155823 A GB155823 A GB 155823A
Authority
GB
United Kingdom
Prior art keywords
relay
circuit
operator
subscriber
jack
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
GB34809/20A
Other languages
English (en)
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.)
Automatic Telephone Manufacturing Co Ltd
Original Assignee
Automatic Telephone Manufacturing Co Ltd
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 Automatic Telephone Manufacturing Co Ltd filed Critical Automatic Telephone Manufacturing Co Ltd
Publication of GB155823A publication Critical patent/GB155823A/en
Expired legal-status Critical Current

Links

Landscapes

  • Interface Circuits In Exchanges (AREA)
GB34809/20A 1919-12-20 1920-12-09 Improvements in or relating to telephone systems Expired GB155823A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US155823XA 1919-12-20 1919-12-20

Publications (1)

Publication Number Publication Date
GB155823A true GB155823A (en) 1921-12-29

Family

ID=21772274

Family Applications (1)

Application Number Title Priority Date Filing Date
GB34809/20A Expired GB155823A (en) 1919-12-20 1920-12-09 Improvements in or relating to telephone systems

Country Status (2)

Country Link
FR (1) FR545108A (enrdf_load_stackoverflow)
GB (1) GB155823A (enrdf_load_stackoverflow)

Also Published As

Publication number Publication date
FR545108A (enrdf_load_stackoverflow) 1922-10-06

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