GB706198A - Improvements in or relating to telephone systems - Google Patents

Improvements in or relating to telephone systems

Info

Publication number
GB706198A
GB706198A GB594551A GB594551A GB706198A GB 706198 A GB706198 A GB 706198A GB 594551 A GB594551 A GB 594551A GB 594551 A GB594551 A GB 594551A GB 706198 A GB706198 A GB 706198A
Authority
GB
United Kingdom
Prior art keywords
line
call
circuit
operates
key
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
GB594551A
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.)
Individual
Original Assignee
Individual
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 BE501787D priority Critical patent/BE501787A/xx
Priority to DES22286A priority patent/DE917316C/de
Application filed by Individual filed Critical Individual
Priority to GB594551A priority patent/GB706198A/en
Publication of GB706198A publication Critical patent/GB706198A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/738—Interface circuits for coupling substations to external telephone lines
    • H04M1/74—Interface circuits for coupling substations to external telephone lines with means for reducing interference; with means for reducing effects due to line faults
    • 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

Landscapes

  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Alarm Systems (AREA)
GB594551A 1950-03-10 1951-03-12 Improvements in or relating to telephone systems Expired GB706198A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
BE501787D BE501787A (US06342305-20020129-C00040.png) 1951-03-12
DES22286A DE917316C (de) 1950-03-10 1951-03-11 Schaltungsanordnung fuer eine Fernsprechanlage
GB594551A GB706198A (en) 1951-03-12 1951-03-12 Improvements in or relating to telephone systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB594551A GB706198A (en) 1951-03-12 1951-03-12 Improvements in or relating to telephone systems

Publications (1)

Publication Number Publication Date
GB706198A true GB706198A (en) 1954-03-24

Family

ID=9805561

Family Applications (1)

Application Number Title Priority Date Filing Date
GB594551A Expired GB706198A (en) 1950-03-10 1951-03-12 Improvements in or relating to telephone systems

Country Status (2)

Country Link
BE (1) BE501787A (US06342305-20020129-C00040.png)
GB (1) GB706198A (US06342305-20020129-C00040.png)

Also Published As

Publication number Publication date
BE501787A (US06342305-20020129-C00040.png)

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