GB601849A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB601849A
GB601849A GB2598645A GB2598645A GB601849A GB 601849 A GB601849 A GB 601849A GB 2598645 A GB2598645 A GB 2598645A GB 2598645 A GB2598645 A GB 2598645A GB 601849 A GB601849 A GB 601849A
Authority
GB
United Kingdom
Prior art keywords
box
line
lever
circuit
call
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
GB2598645A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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
Priority to BE472654D priority Critical patent/BE472654A/xx
Priority to FR956790D priority patent/FR956790A/fr
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB2598645A priority patent/GB601849A/en
Publication of GB601849A publication Critical patent/GB601849A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
    • H04M11/04—Telephonic communication systems specially adapted for combination with other electrical systems with alarm systems, e.g. fire, police or burglar alarm systems
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/16—Security signalling or alarm systems, e.g. redundant systems

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Alarm Systems (AREA)
GB2598645A 1945-10-05 1945-10-05 Improvements in or relating to telephone systems Expired GB601849A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BE472654D BE472654A (enrdf_load_stackoverflow) 1945-10-05
FR956790D FR956790A (enrdf_load_stackoverflow) 1945-10-05
GB2598645A GB601849A (en) 1945-10-05 1945-10-05 Improvements in or relating to telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2598645A GB601849A (en) 1945-10-05 1945-10-05 Improvements in or relating to telephone systems

Publications (1)

Publication Number Publication Date
GB601849A true GB601849A (en) 1948-05-13

Family

ID=10236504

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2598645A Expired GB601849A (en) 1945-10-05 1945-10-05 Improvements in or relating to telephone systems

Country Status (3)

Country Link
BE (1) BE472654A (enrdf_load_stackoverflow)
FR (1) FR956790A (enrdf_load_stackoverflow)
GB (1) GB601849A (enrdf_load_stackoverflow)

Also Published As

Publication number Publication date
FR956790A (enrdf_load_stackoverflow) 1950-02-07
BE472654A (enrdf_load_stackoverflow)

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